Method for manufacturing semiconductor light-emitting device and wavelength conversion member

Abstract

To provide a semiconductor light-emitting device that improves the contrast between a light-emitting surface of the light-emitting device and its surroundings and a manufacturing method for the same.SOLUTION: The semiconductor light-emitting device has a substrate structure, a light-emitting element, a wavelength conversion member, and a first coating member. The substrate structure has a concave portion on the top surface. The light-emitting element is arranged on the bottom surface of the concave portion of the substrate structure and has a semiconductor structural layer including a light-emitting layer. The wavelength conversion member is arranged on the light-emitting element, has a notch formed along a peripheral part on the top surface, and converts a wavelength of emitted light emitted from the light-emitting layer to generate fluorescence. The first coating member includes a plurality of light reflective particles that is arranged on the substrate structure and coats sides of the light-emitting element and sides originating at the periphery of an upper surface of the wavelength conversion member. A reflective film having light reflectivity for the emitted light and fluorescence is deposited on the surface of the notch to cover the surface.SELECTED DRAWING: Figure 2

Description

Technical Field

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

Background Art

[0002] There is disclosed a light-emitting device having a light-emitting element disposed on a substrate and a member having light reflectivity covering a side surface of the light-emitting element. For example, Patent Document 1 discloses a light-emitting device having a light-emitting element disposed on a substrate, a light-transmitting member disposed on the light-emitting element, and a covering member having light reflectivity covering side surfaces of the light-emitting element and the light-transmitting member and exposing an upper surface of the light-transmitting member.

[0003] Further, for example, Patent Document 2 discloses a light-emitting device having a light-transmissive substrate, a plurality of semiconductor layers formed on a growth substrate disposed on the substrate, and a light-reflective layer having light reflectivity covering side surfaces of the substrate, the growth substrate, and the plurality of semiconductor layers.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] In the light-emitting device described in Patent Document 1, light leaks from the upper surface of a covering member (0033 to 0035 in Patent Document 1) made of a light-transmissive resin material and a light-reflective material around the upper edge end of the light-transmissive member, and one of the problems is that the contrast ratio of light between the light-transmissive member and the covering member becomes low.

[0006] Furthermore, in the light-emitting device described in Patent Document 2, one of the problems is that, after manufacturing the light-emitting device which has a substrate, a growth substrate, and a plurality of semiconductor layers, it is necessary to provide a light-reflecting layer to the light-emitting device, and this manufacturing process is time-consuming.

[0007] The present invention has been made in view of the above-mentioned points, and aims to provide a semiconductor light-emitting device and a method for manufacturing the same that improve the contrast between the light-emitting surface of the light-emitting device and its surroundings. [Means for solving the problem]

[0008] The semiconductor light-emitting device according to the present invention comprises a substrate structure having a recess on its upper surface; a light-emitting element disposed on the bottom surface of the recess of the substrate structure and having a semiconductor structural layer including a light-emitting layer; a wavelength conversion member disposed on the light-emitting element and having a notch formed along the periphery of its upper surface, and converting the wavelength of emitted light emitted from the light-emitting layer to generate fluorescence; and a first covering member disposed on the substrate structure and containing a plurality of light-reflective particles that cover the side surface of the light-emitting element and the side surface of the wavelength conversion member that originates from the periphery of the upper surface, wherein a reflective film that is light-reflective to the emitted light and the fluorescence is formed on the surface of the notch so as to cover the surface.

[0009] The present invention provides a method for manufacturing a wavelength conversion member in a semiconductor light-emitting device, comprising: a groove forming step of forming a plurality of grooves in a grid pattern on the upper surface of a plate-shaped wavelength conversion plate; a reflective film forming step of forming a light-reflecting reflective film over the upper surface of the wavelength conversion plate; a reflective film removal step of removing the reflective film formed on the upper surface of the wavelength conversion plate excluding the plurality of grooves; and a piece-forming step of dividing the wavelength conversion plate along each of the plurality of grooves to separate the wavelength conversion member from the wavelength conversion plate into individual pieces. [Brief explanation of the drawing]

[0010] [Figure 1] This is a top view of the light-emitting device according to Example 1. [Figure 2] This is a cross-sectional view of the light-emitting device according to Example 1. [Figure 3] This graph shows the optical reflection characteristics of the reflective film constituting the light-emitting device according to Example 1. [Figure 4] This is an enlarged view of a part of the light-emitting device according to Example 1. [Figure 5] This is a cross-sectional view showing part of the manufacturing process of the wavelength conversion member that constitutes the light-emitting device according to Example 1. [Figure 6] This is a cross-sectional view showing part of the manufacturing process of the wavelength conversion member that constitutes the light-emitting device according to Example 1. [Figure 7] This is a cross-sectional view showing part of the manufacturing process of the wavelength conversion member that constitutes the light-emitting device according to Example 1. [Figure 8] This is a cross-sectional view showing part of the manufacturing process of the wavelength conversion member that constitutes the light-emitting device according to Example 1. [Figure 9] This is a cross-sectional view of the light-emitting device according to Example 2. [Figure 10] This is a cross-sectional view of the light-emitting device according to Example 3. [Modes for carrying out the invention]

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

[0012] The configuration of the light-emitting device 10 according to Embodiment 1 will be described with reference to Figures 1 and 2. Figure 1 is a top view of the light-emitting device 10 according to Embodiment 1. Figure 2 is a cross-sectional view of the light-emitting device 10 shown in Figure 1 along line 2-2. For the sake of simplicity, the X, Y, and Z axes will be defined as shown in Figures 1 and 2. In Figures 1 and 2, the X axis will be described as the left-right direction of the light-emitting device 10, the Y axis as the front-back direction of the light-emitting device 10, and the Z axis as the up-down direction of the light-emitting device 10.

[0013] [Overview of the Light-Emitting Device] The light-emitting device 10 according to Example 1 includes a substrate structure 12 having a recess on its upper surface, a light-emitting element 25 disposed on the bottom surface of the recess, a wavelength conversion member 41 disposed on the light-emitting element 25, and a coating member 45 filled in the recess of the substrate structure 12 so as to cover the side surfaces of the light-emitting element 25 and the wavelength conversion member 41. Further, the light-emitting device 10 includes a protection element 34 disposed in a region different from the light-emitting element 25 on the bottom surface of the recess of the substrate structure 12. In FIG. 1, the coating member 45 is omitted to avoid complication of the drawing.

[0014] [Substrate structure] The substrate structure 12 has a flat plate portion 12A having a rectangular upper surface shape and a frame portion 12B having a frame shape joined to the upper surface of the flat plate portion 12A and along the outer edge of the upper surface. In the substrate structure 12, the upper surface of the flat plate portion 12A is exposed by the opening 12O of the frame portion 12B. In other words, the substrate structure 12 is a structure having a rectangular upper surface shape and having a recess on the upper surface. In FIG. 1, the direction along the long side of the rectangular upper surface shape of the substrate structure 12 or the flat plate portion 12A is defined as the X direction, and the direction along the short side is defined as the Y direction.

[0015] The base materials of the flat plate portion 12A and the frame portion 12B constituting the substrate structure 12 are made of an insulating material. In this example, the base materials of the flat plate portion 12A and the frame portion 12B are made of insulating aluminum nitride (AlN). Note that, for example, insulating ceramics such as aluminum oxide (Al2O3) or silicon nitride (Si3N4) may be used for the flat plate portion 12A and the frame portion 12B.

[0016] Further, conductive first wiring pads 13, second wiring pads 14, third wiring pads 15, and fourth wiring pads 16 are formed on the upper surface of the flat plate portion 12A of the substrate structure 12. Further, conductive first mounting electrodes 17, second mounting electrodes 19, and third mounting electrodes 21 are formed on the lower surface (the lower surface of the light-emitting device 10) of the flat plate portion 12A.

[0017] The first wiring pad 13 is a wiring having a central portion 13A with a rectangular upper surface shape formed substantially at the center of the upper surface of the flat plate portion 12A, and an extended portion 13B with a rectangular upper surface shape that extends from a side parallel to the short side of the substrate structure 12 of the central portion 13A along the long side of the substrate structure 12 to one side. The central portion 13A of the first wiring pad 13 is the portion where the light-emitting element 25 is placed.

[0018] The second wiring pad 14 is a wiring provided separately from the first wiring pad 13 in a region located on the opposite side of the extended portion 13B across the central portion 13A of the first wiring pad 13 on the upper surface of the flat plate portion 12A.

[0019] The third wiring pad 15 is a wiring provided separately from the first wiring pad 13 and the second wiring pad 14 in a region located on the opposite side of the extended portion 13B across the central portion 13A of the first wiring pad 13 on the upper surface of the flat plate portion 12A. In the present embodiment, the third wiring pad 15 is formed adjacent to the second wiring pad 14 in the short side direction of the upper surface of the flat plate portion 12A.

[0020] The fourth wiring pad 16 is a wiring provided separately from the first wiring pad 13, the second wiring pad 14, and the third wiring pad 15 in a region located on the opposite side of the extended portion 13B across the central portion 13A of the first wiring pad 13 on the upper surface of the flat plate portion 12A. The fourth wiring pad 16 is formed adjacent to the third wiring pad 15 in the short side direction of the upper surface of the flat plate portion 12A.

[0021] That is, the second wiring pad 14, the third wiring pad 15, and the fourth wiring pad 16 are arranged in this order along the short side direction of the upper surface of the flat plate portion 12A.

[0022] In the present embodiment, the first wiring pad 13, the second wiring pad 14, the third wiring pad 15, and the fourth wiring pad 16 are each formed by patterning copper (Cu) on the upper surface of the flat plate portion 12A and laminating nickel (Ni) and gold (Au) on its surface in this order.

[0023] The first mounting electrode 17 is a mounting electrode formed on the lower surface region of the flat plate portion 12A, opposite to the formation region of the extended portion 13B of the first wiring pad 13 on the upper surface of the flat plate portion 12A. The first mounting electrode 17 is electrically connected to the first wiring pad 13 via a through hole that penetrates the flat plate portion 12A in the vertical direction and a conductive via 18 made of a conductive material that fills the through hole.

[0024] The second mounting electrode 19 is a mounting electrode formed on the lower surface region of the flat plate portion 12A, opposite to the formation region of the central portion 13A of the first wiring pad 13 on the upper surface of the flat plate portion 12A, and spaced apart from the first mounting electrode 17 and the third mounting electrode 21, which will be described later. The second mounting electrode 19 is electrically connected to the fourth wiring pad 16 and / or the first wiring pad 13 via a connecting wire (not shown) provided between the lower surface of the frame portion 12B and the upper surface of the flat plate portion 12A, and via a conductive via (not shown) consisting of a through hole that penetrates the flat plate portion 12A in the vertical direction and a conductive material filled in the through hole.

[0025] The third mounting electrode 21 is a mounting electrode formed on the lower surface region of the flat plate portion 12A, opposite to the formation regions of the second wiring pad 14 and the third wiring pad 15 on the upper surface of the flat plate portion 12A, and spaced apart from the second mounting electrode 19. The third mounting electrode 21 is electrically connected to the second wiring pad 14 via a through-hole that penetrates the flat plate portion 12A in the vertical direction and a conductive via 22 made of a conductive material filled in the through-hole. The third mounting electrode 21 is also electrically connected to the third wiring pad 15 via a through-hole that penetrates the flat plate portion 12A in the vertical direction and a conductive via (not shown) made of a conductive material filled in the through-hole.

[0026] In other words, the first mounting electrode 17, the second mounting electrode 19, and the third mounting electrode 21 are arranged in this order, spaced apart along the long side direction of the lower surface of the flat plate portion 12A. Furthermore, the first mounting electrode 17 and the second mounting electrode 19 have a first polarity, while the third mounting electrode 21 has a second polarity that is different from the first polarity.

[0027] In this embodiment, the first mounting electrode 17, the second mounting electrode 19, and the third mounting electrode 21 are formed by creating a pattern of Cu on the lower surface of the flat plate portion 12A, and then laminating Ni and Au on its surface in that order. In addition, the conductive vias and connecting wires that penetrate the flat plate portion 12A, including the conductive vias 18 and 22, are formed of Cu.

[0028] [Light-emitting element] The light-emitting element 25 is a light-emitting diode (LED) with a rectangular top surface shape. The light-emitting element 25 is composed of a support substrate 26, a semiconductor structural layer 27, an anode electrode pad 28, and a cathode electrode pad (not shown).

[0029] The support substrate 26 of the light-emitting element 25 is made of conductive silicon (Si) and has a rectangular flat plate shape on its upper surface. The support substrate 26 has a semiconductor structure layer 27 on its upper surface and a cathode electrode (not shown) on its lower surface.

[0030] The semiconductor structural layer 27 of the light-emitting element 25 has a rectangular top surface shape that substantially covers the top surface of the support substrate 26, and is formed so as to expose the support substrate 26 in a frame-like manner in the region of the outer edge of the support substrate 26. In other words, in a top view, the area of ​​the semiconductor structural layer 27 is smaller than the area of ​​the support substrate 26 by the amount of the frame-shaped exposed region of the support substrate 26.

[0031] Furthermore, the semiconductor structural layer 27 has a shape in which one of the four corners of its rectangular top surface is cut out when viewed from above. Specifically, as shown in Figure 1, the semiconductor structural layer 27 has a shape in which the lower right corner in the figure is missing in a fan shape. In other words, in the fan-shaped region of one corner of the top surface of the support substrate 26, the semiconductor structural layer 27 is not formed, and the top surface of the support substrate 26 is exposed.

[0032] The semiconductor structure layer 27 is made of a nitride-based semiconductor such as gallium nitride (GaN), and is a semiconductor layer with light-emitting function in which a p-type semiconductor layer, an emissive layer, and an n-type semiconductor layer are stacked in this order on the upper surface of the support substrate 26 via layers including an insulating layer, a conductive layer, and a reflective layer (not shown). Blue light with a peak wavelength of 450 nm is emitted from the emissive layer of the semiconductor structure layer 27. The emitted blue light is emitted from the upper surface of the semiconductor structure layer 27.

[0033] The anode electrode pad 28 of the light-emitting element 25 is provided in a fan-shaped region on the upper surface of the support substrate 26 where the semiconductor structural layer 27 described above is not formed, and the cathode electrode pad (not shown) is provided on the surface of the support substrate 26 opposite to the surface on which the anode electrode pad 28 is provided (the lower surface of the light-emitting element 25).

[0034] The light-emitting element 25 has its cathode electrode electrically connected to the upper surface of the central portion 13A of the first wiring pad 13 via a conductive element junction layer 29 made of gold-tin (AuSn), and its anode electrode pad 28 is electrically connected to the second wiring pad 14 via a gold (Au) wire, which is the first connecting wire.

[0035] [Protective element] The protection element 34 is a reverse voltage protection element, such as a Zener diode, provided on the fourth wiring pad 16. The protection element 34 has an anode electrode (not shown) on its lower surface, and this anode electrode is electrically connected to the upper surface of the fourth wiring pad 16 via a conductive element junction layer 35 made of AuSn. The protection element 34 also has a cathode electrode pad 36 on its upper surface, which is electrically connected to the third wiring pad 15 via a second connecting wire 37, which is an Au wire.

[0036] With the above configuration, the first mounting electrode 17 and the second mounting electrode 19 are connected to the cathode wiring of the external power supply, and the third mounting electrode 21 is connected to the anode wiring of the external power supply. As a result, power is supplied to the light-emitting element 25 via the first wiring pad 13 and the second wiring pad 14 connected to each mounting electrode, causing it to light up.

[0037] Furthermore, if reverse potential power (noise) is applied from the cathode and anode wiring of an external power supply, the protective elements 34 connected to the third wiring pad 15 and the fourth wiring pad 16 will prevent damage to the light-emitting element 25.

[0038] [Wavelength conversion component] Next, the wavelength conversion member 41 will be described. As shown in Figure 1, the wavelength conversion member 41 has the same rectangular shape as the light-emitting element 25 when viewed from above. More specifically, the wavelength conversion member 41 has the same shape as the support substrate 26 of the light-emitting element 25 when viewed from above.

[0039] The wavelength conversion member 41 is positioned on the light-emitting element 25 and has a rectangular top surface shape that covers the upper surface of the support substrate 26, the semiconductor structural layer 27 formed on the upper surface, and the anode electrode pad 28. The wavelength conversion member 41 is bonded to the light-emitting element 25 via a bonding member 42 that is translucent and contains spacer particles Sp made of spherical particles such as glass.

[0040] The wavelength conversion member 41 is spaced apart by spacer particles Sp so as not to interfere with (contact with) the anode electrode pad 28 and the first connecting wire 31.

[0041] The wavelength conversion member 41 contains phosphor particles that are excited by incident light (blue light) incident from the light-emitting element 25 and emit fluorescence. In this embodiment, the wavelength conversion member 41 is composed of Al2O3 as a base material and phosphor particles of yttrium aluminum garnet (YAG:Ce) with cerium (Ce) contained within the base material as the light-emitting center.

[0042] The concentration of phosphor particles within the wavelength conversion member 41 is adjusted so that the mixed light of light emitted above the wavelength conversion member 41 without exciting the phosphor (blue light) and fluorescence (greenish-yellow light) becomes white light.

[0043] The base material and phosphor of the wavelength conversion member 41 can be selected to produce the light color set in the light-emitting device 10. For example, the base material can be glass or hard silicone resin. The phosphor can also be SiAlON phosphor, CASN(CaAlSiN3) phosphor, SCASN((Sr,Ca)AlSiN3) phosphor, etc.

[0044] The wavelength conversion member 41 has a notch 41N formed along the periphery of the upper surface 41T of the wavelength conversion member 41. Specifically, the wavelength conversion member 41 has a notch 41N formed along the periphery of the upper surface 41T, with the cross-section having a curved surface. Furthermore, a light-reflecting reflective film 43 is formed on the notch surface 41S of the notch 41N of the wavelength conversion member 41 so as to cover the notch surface 41S.

[0045] In other words, the wavelength conversion member 41 has a flat plate portion 41A having a bottom surface that covers the light-emitting element 25, and a pyramidal constricted portion 41B having an upper surface 41T that is smaller than the upper surface of the flat plate portion 41A. A reflective film 43 is formed on the side surface of the constricted portion 41B. The upper surface 41T of the constricted portion 41B functions as the light-emitting surface of the light-emitting device 10 (hereinafter also referred to as the light-emitting surface 41T).

[0046] The reflective film 43 provided on the notched surface 41S is a dielectric multilayer film configured to reflect light from the emitted light (blue light) emitted from the light-emitting element 25 and the fluorescence (greenish-yellow light) emitted from the wavelength conversion member 41.

[0047] The dielectric multilayer film of the reflective film 43 is formed by alternately depositing Al2O3 and titanium oxide (TiO2) from the notched surface 41S of the notched portion 41N.

[0048] In this embodiment, the central wavelength of the blue light emitted from the semiconductor structural layer 27 is 450 nm, and the central wavelength of the greenish-yellow light emitted from the wavelength conversion member 41 is 550 nm. Therefore, a reflective film that reflects light in the visible light band was used. This reflective film 43 is formed by stacking 26 pairs of Al2O3 and TiO2 alternately on the notched surface 41S, with a 200 nm layer of Al2O3 as an underlayer (buffer layer), followed by approximately 50 nm of TiO2. The total thickness of the reflective film 43 is 4.7 μm.

[0049] Figure 3 shows the spectral reflectance characteristics of the reflective film 43. As shown in Figure 3, the reflective film 43 reflects 80% to 90% or more of the light (blue light and greenish-yellow light) that is about to be emitted from the side of the pyramidal constricted portion 41B of the wavelength conversion member 41. In other words, it attenuates the light emitted from the side of the constricted portion 41B to 20% to 10%.

[0050] Furthermore, the reflectivity of the reflective film 43 can be improved by adjusting the film thickness and the number of layered pairs. In addition, silicon dioxide (SiO2), tantalum pentoxide (Ta2O5), and niobium pentoxide (Nb2O5) can also be used as materials other than those mentioned above.

[0051] [Covering material] The covering member 45 is a light-reflective resin material that is arranged so as to expose the upper surface 41T of the wavelength conversion member 41 within the opening 12O, which is the region surrounded by the upper surface of the flat plate portion 12A, which is a recess of the substrate structure 12, the inner surface of the frame portion 12B, and the side surface of the wavelength conversion member 41.

[0052] The covering member 45 reflects light traveling from the side of the wavelength conversion member 41 toward the covering member 45. Therefore, the light reflected by the covering member 45 is emitted from the upper surface 41T of the wavelength conversion member 41 (the light-emitting surface of the light-emitting device 10).

[0053] In this embodiment, the coating member 45 is composed of a translucent silicone resin as a matrix material and white titanium dioxide (TiO2) particles with a particle size of 200 to 300 nm, which are light-scattering particles dispersed within the matrix material.

[0054] The covering member 45 configured in this way reflects light in the visible light band that is incident on the covering member 45. Specifically, a portion of the incident light penetrates into the interior of the covering member 45 while being reflected.

[0055] The TiO2 particle content is preferably 8 wt% to 40 wt%. This is because if the titanium oxide particle content is less than 8 wt%, the amount of light penetrating into the interior of the coating member 45 increases, reducing the reflection effect. Also, if it exceeds 40 wt%, a high reflection effect can be obtained, but cracks may occur in the coating member 45. Furthermore, if it exceeds 40 wt%, the adhesion with the wavelength conversion member 41 may decrease. In this embodiment, the TiO2 particle content is 25 wt%.

[0056] [Improved contrast] Next, we will explain the manner in which contrast is improved using Figure 4. Figure 4 is an enlarged view of the notch 41N and the reflective film 32 formed on its surface, as well as the surrounding area A (dotted line in the figure) in Figure 2.

[0057] The lower end Le of the notch 41N is the upper incident point where the blue light and greenish-yellow light guiding the wavelength conversion member 41 enter the covering member 45 without passing through the reflective film 43. The penetrating circle Pc is a circle drawn with a radius equal to the distance at which the intensity ratio of the light incident from the lower end Le to the covering member 45 attenuates to a predetermined value. In Figure 4, the radius of the penetrating circle Pc is shown as radius Rd, and the depth from the upper surface 45T of the covering member 45 to the lower end Le of the notch 41N is shown as depth D.

[0058] As shown in Figure 4, the side surface of the wavelength conversion member 41 in this embodiment is provided with a reflective film 43 on the notched surface 41S of the notched portion 41N, and further, a covering member 45 is placed on the surface of the reflective film 43 (the side surface of the narrowed portion 41B). Therefore, the intensity of light incident from the notched surface 41S of the wavelength conversion member 41 through the reflective film 43 to the covering member 45 is attenuated by the reflective film 43 to 10% to 20% or less. Consequently, the intensity ratio of light reaching the upper surface 45T of the covering member 45 covering the notched portion 41N of the wavelength conversion member 41 (penetrating light) can be attenuated to 1 / 5 to 1 / 10.

[0059] Furthermore, the depth D from the upper surface 45T of the covering member 45 to the lower end Le of the notch 41N of the wavelength conversion member 41 is set to be greater than or equal to the radius Rd of the penetration circle Pc. Therefore, the intensity ratio of light that enters the covering member 45 from the lower end Le and reaches the upper surface 45T of the covering member 45, which extends upward along the side surface of the wavelength conversion member 41 (penetrating light), can be attenuated to a predetermined value or less.

[0060] The cross-sectional shape of the reflective film 43 is preferable if there are no steps or folds, as this results in more uniform reflection characteristics. Therefore, the cross-sectional shape is preferably an arc or an elliptical arc. However, the side portion of the notch 41N can also be trapezoidal or rectangular if it has a straight section greater than or equal to the radius of the permeation circle Pc.

[0061] The depth D from the upper surface 45T of the covering member 45 to the lower end Le of the notch 41N is preferably greater than the radius Rd at which the intensity of light incident on the covering member 45 from the lower end Le is less than or equal to the intensity ratio defined by the penetration circle Pc at the upper surface 45T. The intensity ratio defined by the penetration circle Pc should be less than or equal to the attenuation ratio of the reflective film 43. For example, if the intensity ratio of light attenuated by the reflective film 43 is 1 / 10, then the radius Rd should be the distance at which the light incident on the covering member 45 from the lower end Le is attenuated to 1 / 10 or less.

[0062] In this embodiment, the strength ratio when the penetration circle Pc is reached is set to 1 / 100. At this strength ratio, the radius Rd of the penetration circle Pc of the covering member 45 is 0.1 mm, so the depth D from the upper surface 45T of the covering member 45 to the lower end Le of the notch 41N is set to 0.15 mm.

[0063] The width W of the notch 41N is preferably 10 to 24 times the total thickness of the reflective film 43. If the width W of the notch 41N is less than 10 times the total thickness, it becomes difficult to form the reflective film 43. If it is more than 24 times, the area of ​​the light-emitting surface 41T becomes small. Preferably, it is 14 to 20 times, which makes it easy to form the reflective film 43 and suppresses the reduction in the area of ​​the light-emitting surface 41T. In this embodiment, the total thickness of the reflective film is 4.7 μm and the width W of the notch is 0.08 mm.

[0064] Thus, according to this embodiment, by attenuating the light intensity incident from the notched surface 41S of the wavelength conversion member 41 to the covering member 45, and the light intensity incident from the lower end Le to the covering member 45 and reaching the upper surface 45T, the difference in brightness (contrast) between the outer periphery of the upper surface 41T of the wavelength conversion member 41 and the upper surface 45T of the covering member 45 in contact with the outer periphery can be increased.

[0065] [Manufacturing method for wavelength conversion components] The manufacturing method for the wavelength conversion member 41 on which the reflective film 43 is formed will be described below with reference to Figures 5 to 8. Figures 5 to 8 are cross-sectional views showing a part of the manufacturing process of the wavelength conversion member 41 in this embodiment. Note that some parts of the member are omitted in Figures 5 to 8.

[0066] First, a flat wavelength conversion plate 41M, which is in the state before the formation of the wavelength conversion member 41, is prepared, and multiple grooves Gr are formed in a grid pattern on the upper surface of the wavelength conversion plate 41M using a dicing machine equipped with a dicing blade with a rounded tip (Step 1, groove formation step). This step makes it possible to form grooves Gr that have a curved surface in cross-sectional view, as shown in Figure 5. In this embodiment, a light-emitting element 25 with an upper surface shape of 1 mm square was used, so the groove formation pitch Gr was set to 1 mm. In addition, the groove width Gr was formed to 0.16 mm so that the width W of the notch portion 41N is 0.08 mm.

[0067] Next, as shown in Figure 6, a dielectric multilayer film as a reflective film 43M is formed on the upper surface of the wavelength conversion plate 41M, including the surface of the groove Gr, using sputtering or atomic layer deposition (ALD) (Step 2, reflective film formation step).

[0068] In this step, as described above, in order to form a multilayer reflector suitable for reflecting light in the visible light band including blue light and greenish-yellow light, a 200 nm layer of Al2O3 was deposited on the upper surface of the wavelength conversion plate 41M as an underlayer, and 26 pairs of TiO2 and Al2O3 were stacked alternately on top of it so that the thickness of each layer gradually increased, forming a reflective film 43M with a total thickness of 4.7 μm.

[0069] Next, as shown in Figure 7, the reflective film 43M formed on the upper surface of the wavelength conversion plate 41M, excluding each of the multiple grooves Gr, is removed by mechanical polishing (Step 3, Reflective Film Removal Step). This step makes it possible to have a state where the reflective film 43M is formed only on the surface of each of the multiple grooves Gr.

[0070] Finally, as shown in Figure 8, the wavelength conversion plate 41M is fully die-cut in a grid pattern along each of the multiple grooves Gr using a dicing machine to separate the wavelength conversion members 41 into individual pieces (Step 4, individual piece formation step). This step makes it possible to manufacture a 1 mm square wavelength conversion member 41 with a notch 41N having a width W of 0.08 mm and a reflective film 43 formed on the notch surface 41S.

[0071] According to steps 1 to 4 described above, a wavelength conversion member 41 can be obtained in which the reflective film 43M is formed only on the notched surface 41S of the notched portion 41N, and the reflective film 43M is not formed on the cut surface when the wavelength conversion member 41 is separated into individual pieces.

[0072] [Manufacturing method for light-emitting devices] Next, a method for manufacturing the light-emitting device 10 using the wavelength conversion member 41 manufactured by the method described above will be explained based on Figures 1 and 2.

[0073] First, a substrate structure 12 is prepared, having a flat plate portion 12A on which various wiring pads are formed and a frame portion 12B formed on the flat plate portion 12A. Then, a light-emitting element 25 and a protective element 34 are bonded to the flat plate portion 12A (Step S1, element bonding process).

[0074] Specifically, first, solder paste, consisting of AuSn particles and flux, which are the raw materials for the element junction layer 29 and element junction layer 35, is applied to the central portion 13A of the first wiring pad 13 and the upper surface of the fourth wiring pad 16, respectively. Then, the light-emitting element 25 and the protective element 34 are placed on the central portion 13A of the first wiring pad 13 and the upper surface of the fourth wiring pad 16, respectively.

[0075] Subsequently, the substrate structure 12 on which the light-emitting element 25 and the protective element 34 are placed is heated in a reflow oven at approximately 300°C, melting and solidifying the AuSn particles contained in the solder paste, thereby bonding the light-emitting element 25 and the protective element 34 to the wiring pads of the substrate structure 12.

[0076] Next, the anode electrode pad 28 of the light-emitting element 25 and the second wiring pad 14 are connected with the first connecting wire 31, and the cathode electrode pad 36 of the protective element 34 and the third wiring pad 15 are connected with the second connecting wire 37 (step S2, wire bonding process).

[0077] Specifically, a shim bump is formed on the anode electrode pad 28 of the light-emitting element 25, one end of the first connecting wire 31 is bonded to the second wiring pad 14, and the other end of the first connecting wire 31 is bonded to the shim bump of the anode electrode pad 28, thereby connecting the light-emitting element 25 and the second wiring pad 14 with a wire.

[0078] Furthermore, the protective element 34 and the third wiring pad 15 are wire-connected by bonding one end of the second connecting wire 37 to the third wiring pad 15 and bonding the other end of the second connecting wire 37 to the cathode electrode pad 36 of the protective element 34.

[0079] Next, the wavelength conversion member 41 is bonded onto the light-emitting element 25 (step S3, wavelength conversion member bonding step). In this step, a predetermined amount of uncured silicone resin as the bonding member 42 is applied onto the semiconductor structural layer 27 of the light-emitting element 25, and the resin is left to stand until the spacer particles Sp contained in the resin settle within the resin.

[0080] Subsequently, using a mounter, the wavelength conversion member 41 is placed on the light-emitting element 25 coated with silicone resin and pressed down so that the outer edge of the wavelength conversion member 41 and the outer edge of the light-emitting element 25 coincide. This process allows the upper surface of the semiconductor structure layer 27 and the lower surface of the wavelength conversion member 41 to be joined at an interval corresponding to the outer diameter of the spacer particle Sp, as described above. This allows the wavelength conversion member 41 to be joined while maintaining clearance so as not to interfere with the anode electrode pad 28 and the first connecting wire 31.

[0081] Finally, a covering member 45 is formed in the opening 12O of the substrate structure 12, covering the sides of the light-emitting element 25 and the wavelength conversion member 41, with the upper surface 41T of the wavelength conversion member 41 exposed (step S4, covering member formation step). Specifically, a predetermined amount of precursor resin for the covering member 45, which is made of uncured silicone resin with TiO2 particles dispersed in it, is filled into the recess of the substrate structure 12 so as to expose the upper surface 41T of the wavelength conversion member 41.

[0082] Subsequently, the substrate structure 12 filled with the precursor resin of the coating member 45 is heated at 150°C for 60 minutes to cure the silicone resin and form the coating member 45.

[0083] By performing the steps S1 to S4 described above, the light-emitting device 10 in this embodiment can be manufactured.

[0084] In this embodiment, the steps S1 to S4 described above enable the easy manufacture of the wavelength conversion member 41 equipped with the reflective film 43. Furthermore, by using the wavelength conversion member 41 equipped with the reflective film 43 in the notched portion 41N, the light-emitting device 10 incorporating the wavelength conversion member 41 equipped with the reflective film 43 can be manufactured in steps S1 to S4 without requiring any special processes.

[0085] [Examples 2 and 3] Next, Examples 2 and 3 will be described. Figure 9 is a cross-sectional view of the light-emitting device 50 of Example 2, and Figure 10 is a cross-sectional view of the light-emitting device 60 of Example 3. Each cross-sectional view shows a cross-section at a similar position to the cross-section along line 2-2 shown in Example 1.

[0086] The light-emitting device 50 of Example 2 and the light-emitting device 60 of Example 3 differ only in a few aspects from the light-emitting device 10 of Example 1, and the configuration of the substrate structure 12, light-emitting element 25, wavelength conversion member 41, and protective element 34 are the same as those of Example 1. In describing the light-emitting devices 50 and 60, the same components and parts as those of the light-emitting device 10 of Example 1 are given the same names and numbering. [Examples]

[0087] The coating member 45 of the light-emitting device 50 contains TiO2 particles having a band gap smaller than the band gap of TiO2 particles dispersed outside the surface region SR, in the surface region SR from the top surface of the coating member 45 to a depth of several μm.

[0088] Specifically, each TiO2 particle dispersed in the surface region SR of the coating member 45 has a band gap energy smaller than the energy of visible light. In other words, the TiO2 particles dispersed in the surface region SR absorb visible light. The surface region of such a coating member 45 is black or gray in color.

[0089] In this embodiment, the thickness of the surface region SR is sufficiently thinner than the depth D of the notch 41N. Therefore, the light reflection characteristics of the portion where the side surface of the wavelength conversion member 41 without the reflective film 43 is in contact with the covering member 45 are not impaired. In contrast, in the region of the covering member 45 that is in contact with the outer surface of the wavelength conversion member 41 with the reflective film 43, the light attenuated by the reflective film 43 is absorbed by the surface region SR. As a result, the contrast at the boundary between the wavelength conversion member 41 and the covering member 45 can be improved to a level greater than that of Embodiment 1 without attenuating the light emitted from the light-emitting surface 41T.

[0090] The configuration of the coating member 45 described above is obtained by performing a blackening process on the TiO2 particles dispersed in the surface region SR of the coating member 45 after the manufacturing of the light-emitting device 10 of Example 1 (Step S5: Blackening process). Specifically, by irradiating the upper surface of the coating member 45 with ultraviolet laser light having an energy equivalent to or greater than the band gap of TiO2 using a laser light source, the TiO2 particles dispersed in the surface region SR can be blackened, and a light-absorbing layer can be created in the surface region SR.

[0091] In detail, the TiO2 particles in the surface region SR of the coating member 45 undergo partial oxygen deficiency upon irradiation with ultraviolet laser light, forming a region with a small band gap that absorbs visible light. In this way, the light-emitting device 50 can be manufactured by simply adding an extremely simple processing step. [Examples]

[0092] The covering member of the light-emitting device 60 has a two-layer structure in which a light-absorbing covering member 51 is laminated on the upper surface of a covering member 45. Specifically, the covering member 45, as the first covering member, is formed up to the height of the lower end Le of the notch portion 41N of the wavelength conversion member 41, and the covering member 51, which contains a light-absorbing material and serves as the second covering member, is formed on its upper surface up to the height of the upper end Te of the notch portion 41N. The covering member 51 is formed to reach the upper end of the frame portion 12B of the substrate structure 12.

[0093] The coating member 51 is a resin material in which a silicone resin matrix material contains visible light absorbing carbon black particles with a particle size of several nanometers to several tens of nanometers.

[0094] In this embodiment, the light reflection characteristics of the portion where the side surface of the wavelength conversion member 41 without the reflective film 43 is in contact with the covering member 45 are attenuated near the lower end Le of the notch 41N by the amount of light that penetrates the covering member 45 and the covering member 51 that does not return.

[0095] Furthermore, in the region where the reflective film 43 is provided, the light that is attenuated by the reflective film 43 and incident on the covering member 51 is absorbed by the covering member 51, so the light emitted from the light-emitting surface 41T is attenuated. However, in this embodiment, the reflective film 43 suppresses the light that penetrates and is absorbed by the covering member 51, and there is no light leakage from the covering member 51, so the contrast at the boundary between the wavelength conversion member 41 and the black covering member 51 can be improved.

[0096] The laminated structure of the light-reflective coating member 45 and the light-absorbing coating member 51 described above can be formed by a forming method in which the coating member 45 and the coating member 51 are divided and filled, instead of step S4 of Example 1 (step S4B: two-layer coating member formation step).

[0097] Specifically, a precursor resin for a coating member 45, made of uncured silicone resin with dispersed TiO2 particles, is filled into the recess of the substrate structure 12 so as to expose the upper surface, including the surface of the notch 41N of the wavelength conversion member 41. Next, a precursor resin for a coating member 51, made of uncured silicone resin with dispersed carbon black powder, is filled in so as to fill the notch 41N of the wavelength conversion member 41 and expose only the upper surface 41T.

[0098] Subsequently, the substrate structure 12, which is filled with the respective precursor resins of the coating members 45 and 51, is heated at 150°C for 60 minutes to cure the silicone resin, thereby forming the coating members 45 and 51.

[0099] According to this embodiment, when filling the substrate structure 12 with the precursor resin of the coating member 45, the precursor resin of the coating member 45 can be filled in line with the lower end of the notch 41N, thus preventing the coating member 45 from creeping up from the lower end of the notch 41N. In this way, by providing the wavelength conversion member 41 with the notch 41N, it becomes possible to easily manufacture a light-emitting device 60 having a two-layer laminated coating member.

[0100] In Examples 2 and 3, as in Example 1, the formation of the reflective layer 57 suppresses light that would otherwise leak out from around the upper surface 56T of the wavelength conversion member 56, thereby improving the contrast ratio at the boundary between the wavelength conversion member 56 and the covering member 45.

[0101] The present invention has been described based on Examples 1 to 3, but the above examples are merely illustrative, and the configuration, shape, dimensions, materials, etc. can be changed or selected as appropriate within the scope of the spirit of the invention.

[0102] For example, the reflection band of the reflective film provided in the notch of the wavelength conversion member only needs to be adjusted to match the band of light emitted from the light-emitting device.

[0103] Furthermore, although the examples described used a light-emitting device with a wavelength conversion member containing a phosphor, the method can also be applied to light-emitting devices in which the wavelength conversion member is a transparent material (e.g., glass) that does not contain a phosphor.

[0104] Furthermore, this method can also be applied to light-emitting devices that have a wavelength conversion member on a semiconductor structural layer, excluding the electrode pads provided on the upper surface of the light-emitting element. In this case, it is not necessary to add spacer particles to the bonding member that adheres the wavelength conversion member to the light-emitting element.

[0105] Furthermore, for example, this can also be applied to a light-emitting device in which a light-emitting element, in which both the anode electrode pad and cathode electrode pad are provided on a semiconductor structural layer and the support substrate is a translucent substrate, is flip-mounted on the wiring pad of the substrate structure, and a wavelength conversion member is bonded to the support substrate surface (upper surface) of the light-emitting element. In this case, it is sufficient if the peripheral shape (outer shape) of the wavelength conversion member is approximately the same as the peripheral shape (outer shape) of the light-emitting element.

[0106] Furthermore, it can also be applied to a light-emitting device that has multiple light-emitting elements arranged in close proximity and is equipped with a wavelength conversion member that covers the upper surfaces of the multiple light-emitting elements.

[0107] As described above, the present invention provides a light-emitting device equipped with a light-emitting surface with high contrast and a simple method for manufacturing the light-emitting device. [Explanation of Symbols]

[0108] 10, 50, 60 Light-emitting devices 12. Substrate Structure 12A flat plate part 12B Frame body part 13. First wiring pad 14. Second wiring pad 15. Third wiring pad 16. Fourth wiring pad 17. First mounting electrode 18. First conductive via 19. Second mounting electrode 21 Third mounting electrode 22 Second conductive via 25 Light-emitting element 26 Support substrate 27 Semiconductor structural layers 28 Anode electrode pads 29 Element junction layer 31. First connecting wire 34 protective elements 35 element junction layer 36 Cathode electrode pads 37. Second connecting wire 41, 53, 56 Wavelength conversion components 42 Joining members 43 Reflective film 45, 51 Covering member

Claims

1. A substrate structure having a recess on its upper surface, A light-emitting element is disposed on the bottom surface of the recess of the substrate structure and has a semiconductor structural layer including a light-emitting layer, A wavelength conversion member is disposed on the light-emitting element and has a flat plate shape with a cross section formed continuously along the periphery of its upper surface, which has an arc-shaped or elliptical arc-shaped notch, and has a tapered portion that narrows upward, and converts the wavelength of the emitted light emitted from the light-emitting layer to generate fluorescence. It comprises a first covering member disposed on the substrate structure and covering the entire side surface of the light-emitting element and the wavelength conversion member, A reflective film having light reflectivity to the emitted light and the fluorescence is formed only on the surface of the notched portion. The first coating member is composed of a resin and light-scattering particles dispersed within the resin, and reflects light incident on the first coating member. The semiconductor light-emitting device wherein the reflective film is made of a dielectric multilayer film, and an underlayer is formed between the reflective film and the surface of the notch.

2. The semiconductor light-emitting apparatus according to claim 1, characterized in that the width of the notch is 10 to 24 times the thickness of the reflective film.

3. The semiconductor light-emitting apparatus according to claim 1 or 2, characterized in that the first coating member comprises a matrix material made of resin and titanium oxide particles held in the matrix material.

4. The semiconductor light-emitting apparatus according to claim 3, characterized in that the first coating member contains titanium oxide particles having a smaller band gap than the titanium oxide particles in a region from the upper surface of the first coating member to a predetermined depth.

5. The semiconductor light-emitting apparatus according to claim 1 or 2, characterized in that the notch is formed such that the depth from the upper surface of the first covering member to the lower end of the notch is greater than the radius of the penetration circle of the emitted light or the fluorescence into the first covering member when the outer end of the notch is the incident point of the emitted light or the fluorescence.

6. The semiconductor light-emitting apparatus according to claim 1 or 2, characterized in that the distance from the surface of the first covering member to the lower end of the notch is the radius of the penetrating circle such that the intensity ratio of the light attenuated by the reflective film is less than or equal to that of the light attenuated by the reflective film.

7. A method for manufacturing a wavelength conversion member, A groove forming step in which multiple grooves are formed in a grid pattern on the upper surface of a plate-shaped wavelength conversion plate, A reflective film forming step of forming a reflective film having light reflectivity over the upper surface of the wavelength conversion plate, A reflective film removal step, which involves removing the reflective film formed on the upper surface of the wavelength conversion plate excluding the plurality of grooves, A fragmentation step of dividing the wavelength conversion plate along each of the plurality of grooves and fragmenting the wavelength conversion member from the wavelength conversion plate, A method for manufacturing a wavelength conversion member, characterized by having the following features.

8. A method for manufacturing a semiconductor light-emitting apparatus, comprising: a substrate structure having a recess on its upper surface; a light-emitting element disposed on the bottom surface of the recess of the substrate structure and having a semiconductor structure layer including a light-emitting layer; a wavelength conversion member disposed on the light-emitting element and having a notch provided along the periphery of its upper surface, and converting the wavelength of emitted light emitted from the light-emitting layer to generate fluorescence; and a first coating member disposed on the substrate structure and including a plurality of light-reflective particles that cover the side surface of the light-emitting element and the side surface of the wavelength conversion member that ends at the periphery of the upper surface, A substrate structure preparation step involves preparing a substrate structure in which the recess is formed by a flat plate portion on which a wiring pad is formed on the upper surface and a frame portion formed on the upper surface of the flat plate portion, A wavelength conversion member manufacturing step comprising: a groove forming step of forming a plurality of grooves in a grid pattern on the upper surface of a plate-shaped wavelength conversion plate; a reflective film forming step of forming a light-reflecting reflective film over the upper surface of the wavelength conversion plate; a reflective film removal step of removing the reflective film formed on the upper surface of the wavelength conversion plate excluding the plurality of grooves; and a piece forming step of dividing the wavelength conversion plate along each of the plurality of grooves to separate the wavelength conversion members from the wavelength conversion plate into individual pieces; A component connection step involves placing the light-emitting element on the bottom surface of the recess of the substrate structure and electrically connecting the wiring pad and the light-emitting element, A wavelength conversion member bonding step of bonding the individual wavelength conversion members onto the light-emitting element, The step includes forming a covering member, which involves forming the first covering member within the recess of the substrate structure such that it covers the side surface of the light-emitting element and the side surface of the wavelength conversion member, and exposes the upper surface of the wavelength conversion member. A method for manufacturing a semiconductor light-emitting device, wherein in the step of forming the covering member, the first covering member covers the reflective film.

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