Semiconductor light emitting device

Abstract

The present invention includes: a substrate; a light emitting element provided on one main surface of the substrate and including a light emitting layer containing a semiconductor; a phosphor layer formed on the one main surface to cover the light emitting element, the phosphor layer including phosphor particles excited by light emitted from the light emitting layer and emitting phosphor light, and having a frame-shaped portion continuously formed on a periphery of the phosphor layer and protruding from a lower end of a side surface toward a side of the one main surface; a light-transmissive sealing layer covering an upper surface of the phosphor layer, extending from an upper end of the side surface to cover the side surface, and stopping at an upper surface of the frame-shaped portion; and a transmissive reflective layer formed on an upper surface of the sealing layer, the transmissive reflective layer partially reflecting and partially transmitting each of light emitted from the light emitting layer and phosphor light emitted from the phosphor layer.

Description

Technical Field

[0001] This invention relates to a semiconductor light-emitting device including a light-emitting element. Background Technology

[0002] A light-emitting device is disclosed that includes a phosphor layer containing a light-emitting element covered by a transparent resin layer. For example, Patent Document 1 discloses a light-emitting device that includes a light-emitting element disposed on a substrate, a color-conversion encapsulation containing color-conversion particles formed to house the light-emitting element on the substrate, and a transparent encapsulation made of resin covering the entire color-conversion encapsulation.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2022-162976 Summary of the Invention

[0006] The problem to be solved by the present invention

[0007] When manufacturing the light-emitting device disclosed in Patent Document 1, for example, when a dicing tool is used to separate the color conversion package into individual light-emitting devices after the color conversion package is formed, there is a possibility that the blade of the dicing tool may reach the substrate.

[0008] If, as described above, the dicing blade reaches the substrate when the color conversion package is being separated, the substrate may become bent, and there is a possibility that the color conversion package may peel off from the substrate or the wiring formed on the substrate may break. If this occurs, the yield in manufacturing the light-emitting device will decrease.

[0009] In the light-emitting device disclosed in Patent Document 1, the emitted light has a Lambertian light distribution. Therefore, in environments where a light distribution with a wider angle than the Lambertian light distribution is required, such as for auxiliary lights in vehicles, the light-emitting device disclosed in Patent Document 1 may not be usable as a light source.

[0010] The present invention was made in view of the above-mentioned problems, and one object of the present invention is to provide a semiconductor light-emitting device that can improve the yield during manufacturing while achieving a wide-angle light distribution.

[0011] Problem-solving methods

[0012] A semiconductor light-emitting device according to the present invention includes: a substrate, a light-emitting element, a phosphor layer, a light-transmitting sealing layer, and a transmission-reflection layer. The light-emitting element includes a light-emitting layer made of semiconductor disposed on a main surface of the substrate. The phosphor layer is formed on the main surface to cover the light-emitting element, the phosphor layer having a frame-like portion that protrudes laterally from a lower end of a side surface along the main surface and is continuously formed around the periphery of the phosphor layer in a top view. The phosphor layer has phosphor particles that emit fluorescence when excited by light emitted from the light-emitting layer. The light-transmitting sealing layer covers the upper surface of the phosphor layer, extends from the upper end of the side surface to cover the side surface, and terminates at the upper surface of the frame-like portion. The transmission-reflection layer is formed on the upper surface of the sealing layer to partially reflect and partially transmit each of the light emitted from the light-emitting layer and the fluorescence emitted from the phosphor layer. Attached Figure Description

[0013] Figure 1 This is a top view of the light-emitting device according to Embodiment 1.

[0014] Figure 2 This is a bottom view of the light-emitting device according to Embodiment 1.

[0015] Figure 3 This is a cross-sectional view of the light-emitting device according to Embodiment 1.

[0016] Figure 4 This is a cross-sectional view of the light-emitting device according to Embodiment 1.

[0017] Figure 5 This is a table showing the confirmation results of the light-emitting device according to Embodiment 1.

[0018] Figure 6 This is a cross-sectional view of the manufacturing process of the first manufacturing method of the light-emitting device according to Embodiment 1.

[0019] Figure 7 This is a cross-sectional view of the manufacturing process of the first manufacturing method of the light-emitting device according to Embodiment 1.

[0020] Figure 8 This is a cross-sectional view of the manufacturing process of the first manufacturing method of the light-emitting device according to Embodiment 1.

[0021] Figure 9 This is a cross-sectional view of the manufacturing process of the first manufacturing method of the light-emitting device according to Embodiment 1.

[0022] Figure 10 This is a cross-sectional view of the manufacturing process of the first manufacturing method of the light-emitting device according to Embodiment 1.

[0023] Figure 11 This is a cross-sectional view of the manufacturing process of the second manufacturing method of the light-emitting device according to Embodiment 1.

[0024] Figure 12 This is a cross-sectional view of the manufacturing process of the second manufacturing method of the light-emitting device according to Embodiment 1.

[0025] Figure 13 This is a cross-sectional view illustrating the manufacturing process of the second manufacturing method of the light-emitting device according to Embodiment 1. And...

[0026] Figure 14 This is a cross-sectional view of the manufacturing process of the second manufacturing method of the light-emitting device according to Embodiment 1. Detailed Implementation

[0027] The following is a detailed description of embodiments of the present invention with reference to the accompanying drawings. In the drawings, the same reference numerals are used to designate substantially the same or equivalent parts, and descriptions of repeated parts are omitted.

[0028] Implementation Method 1

[0029] [Overview of the light-emitting device 100]

[0030] use Figures 1 to 4 The structure of the light-emitting device 100 in Embodiment 1 will be explained. Figure 1 This is a top view of the light-emitting device 100 according to Embodiment 1. Figure 2 This is a bottom view of the light-emitting device 100 according to Embodiment 1. Figure 3 yes Figure 1 A cross-sectional view of the light-emitting device 100 along line 3-3. Figure 4 yes Figure 1 A cross-sectional view of the light-emitting device 100 along line 4-4.

[0031] exist Figure 1 and Figure 2 In the diagram, the center line (bisector) of the width direction (left-right direction in the diagram) of the light-emitting device 100 is represented by a dashed line as center line CL1, and the center line (bisector) of the depth direction (up-down direction in the diagram) of the light-emitting device 100 is represented by a dashed line as center line CL2.

[0032] exist Figure 3 In the diagram, the left-right direction represents the width of the light-emitting device 100, and the up-down direction represents its height. Figure 4 In the figure, the left and right directions represent the depth of the light-emitting device 100, and the up and down directions represent the height of the light-emitting device 100.

[0033] like Figure 3 and Figure 4As illustrated, the light-emitting device 100 is configured to include a substrate 11, a light-emitting element 13 disposed above the substrate 11, a phosphor layer 15 formed above the substrate 11 to cover the light-emitting element 13, a sealing layer 17 formed to cover the phosphor layer 15, and a transmission and reflection layer 19 formed on the upper surface of the sealing layer 17.

[0034] [Substrate 11]

[0035] First, the substrate 11 will be described. The substrate 11 is a flat glass epoxy board (FR-4) with a rectangular upper surface and possesses insulating properties. Alternatively, a ceramic substrate made of alumina (Al2O3) or aluminum nitride (AlN) can be used for the substrate 11. Anode pads 21 and cathode pads 22 are formed on the upper surface of the substrate 11. An anode electrode 23 and a cathode electrode 24 are formed on the lower surface of the substrate 11.

[0036] Anode pad 21 and cathode pad 22 are a pair of component mounting pads, each having a rectangular upper surface shape. The pair of component mounting pads are separated from each other to clamp a centerline CL1 formed on the upper surface of the substrate 11.

[0037] The anode pad 21 has two extensions 21A that extend from their respective short sides along the center line CL1 and reach the outer edge of the substrate 11. The anode pad 21 also has two extensions 21B that extend from one long side along the center line CL2 to clamp the center line CL2 and reach the outer edge of the substrate 11.

[0038] Similar to the anode pad 21, the cathode pad 22 has two extensions 22A that extend along the centerline CL1 from the respective short sides and reach the outer edge of the substrate 11. The cathode pad 22 also has two extensions 22B that extend from a long side along the centerline CL2 to clamp the centerline CL2 and reach the outer edge of the substrate 11.

[0039] Anode electrode 23 and cathode electrode 24 are a pair of electrodes, each having a rectangular upper surface shape. These electrodes are separated from each other to clamp a centerline CL2 on the lower surface of substrate 11. In the light-emitting device 100, in a top view of substrate 11, the longitudinal directions of anode pad 21 and cathode pad 22 are orthogonal to the longitudinal directions of anode electrode 23 and cathode electrode 24.

[0040] Each of the anode pad 21, cathode pad 22, anode electrode 23, and cathode electrode 24 is made of copper (Cu) and has a nickel (Ni) plating and a gold (Au) plating applied to its surface in this order. For plating treatment, silver (Ag) plating can be used instead of Au plating.

[0041] In the light-emitting device 100, the anode pad 21 and the anode electrode 23 are electrically connected through a conductive via 25 made of Cu material. Similarly, the cathode pad 22 and the cathode electrode 24 are electrically connected through a conductive via 25.

[0042] [Light-emitting element 13]

[0043] Next, the light-emitting element 13 will be described. As described above, the light-emitting element 13 is disposed on the upper surface of the substrate 11 and is a light-emitting diode (LED) having a rectangular upper surface shape.

[0044] like Figure 3 and Figure 4 As illustrated, the light-emitting element 13 is configured to include: a semiconductor structure layer 27 having a light-emitting layer made of semiconductor; and a light-transmitting substrate 28 disposed on the upper surface of the semiconductor structure layer 27.

[0045] Semiconductor structure layer 27 is a semiconductor layered structure consisting of an n-type semiconductor layer, a light-emitting layer, and a p-type semiconductor layer (not shown) made of gallium nitride (GaN) as the main material. When the light-emitting element 13 is driven, blue light with a peak wavelength of 450 nm is emitted from the light-emitting layer of semiconductor structure layer 27.

[0046] The light-transmitting substrate 28 is a flat substrate with a rectangular upper surface. The light-transmitting substrate 28 is made of a material (e.g., sapphire (Al2O3) or GaN) that is transparent to blue light emitted from the light-emitting layer of the semiconductor structure layer 27 and fluorescence emitted from the phosphor layer 15 described below. The light-transmitting substrate 28 is also the substrate used for growing the semiconductor structure layer 27.

[0047] The light-emitting element 13 includes a p-electrode 31 and an n-electrode 32, each formed on the lower surface of the semiconductor structure layer 27 and having a rectangular upper surface shape. The p-electrode 31 is an electrode electrically connected to the p-type semiconductor layer of the semiconductor structure layer 27. The p-electrode 31 is plated with gold (Au) on its surface.

[0048] The n-electrode 32 is an electrode electrically connected to the n-type semiconductor layer via a through-electrode (not shown) that penetrates the light-emitting layer and the p-type semiconductor layer of the semiconductor structure layer 27 in the vertical direction and has a side surface covered with an insulator. In other words, the n-electrode 32 is electrically connected only to the n-type semiconductor layer and is insulated from the light-emitting layer and the p-type semiconductor layer. Au is plated on the surface of the n-electrode 32.

[0049] The p electrode 31 and n electrode 32 are connected to the anode pad 21 and the cathode pad 22 respectively via epoxy resin solder 33. That is, in the light-emitting device 100, the light-emitting element 13 is flip-chip mounted on the substrate 11.

[0050] The epoxy resin solder 33 contains tin-silver-copper (Sn-Ag-Cu) and other solder metal particles in the epoxy resin flux, and after bonding, the epoxy resin covers the area around the solder joint to increase its bonding strength. Furthermore, since the area around the solder joint is covered by epoxy resin, adhesion to the phosphor layer 15 is improved, which is preferred. As the epoxy resin solder 33, a gold-tin (Au-Sn) solder utilizing a volatile flux can be used.

[0051] [Fluorescent layer 15]

[0052] Next, the phosphor layer 15 will be described. The phosphor layer 15 has a rectangular upper surface shape and is disposed on the substrate 11 to surround the light-emitting element 13. The phosphor layer 15 includes a frame-like portion 15F that protrudes laterally from the lower end of the side surface along the upper surface of the substrate 11 and is continuously formed around the periphery of the phosphor layer 15 in a top view. The frame-like portion 15F extends from the lower end of the side surface of the phosphor layer 15 to the outer edge of the substrate 11.

[0053] The phosphor layer 15 includes a phosphor that emits fluorescence when excited by blue light emitted from the light-emitting element 13. When excited by blue light, the phosphor layer 15 emits green fluorescence with a peak wavelength in the range of 500 nm to 580 nm and red fluorescence with a peak wavelength in the range of 620 nm to 640 nm.

[0054] The phosphor layer 15 is composed of KSF (K2SiF6:Mn) phosphor particles that emit red fluorescence and β-thion phosphor particles that emit green fluorescence, dispersed in a light-transmitting resin (e.g., silicone resin).

[0055] When the blue light emitted from the light-emitting element 13 enters the phosphor layer 15, a portion of it passes through the phosphor layer 15 as is, and a portion of it excites the phosphor particles, causing the excited phosphor particles to emit fluorescence.

[0056] Therefore, excitation light (blue light) that passes through the phosphor layer 15 and does not contribute to the generation of fluorescence, and fluorescence (green and red light) emitted from the phosphor particles are emitted from the upper surface of the phosphor layer 15. As a result, white light, which is a mixture of blue light, red fluorescence, and green fluorescence, is extracted from the upper surface of the phosphor layer 15.

[0057] [Sealing layer 17]

[0058] Next, the sealing layer 17 will be described. The sealing layer 17 is a light-transmitting layer that covers the upper surface of the phosphor layer 15, extends from the upper end of the side surface of the phosphor layer 15 to cover the side surface, and terminates at the upper surface of the frame-shaped portion 15F. The sealing layer 17 is made of silicone resin that transmits white light (specifically, white band light).

[0059] The sealing layer 17 covers most of the phosphor layer 15 to act as a protective layer, protecting the KSF phosphor from external air, which is easily altered by moisture. The sealing layer 17 also functions as a light guide layer to direct the white light emitted from the phosphor layer 15.

[0060] [Transmission and Reflection Layer 19]

[0061] Next, the transmission-reflection layer 19 will be described. As described above, the transmission-reflection layer 19 is formed on the upper surface of the sealing layer 17 and is a layer that reflects a portion of the white light propagating and emitted through the sealing layer 17 while simultaneously transmitting a portion of it.

[0062] In the light-emitting device 100 of this embodiment, the transmission and reflection layer 19 is a dielectric multilayer film whose thickness is adjusted to make the reflectivity to white light a predetermined value. The dielectric multilayer film is suitable for controlling light distribution characteristics (direction characteristics) because it generates transmitted and reflected light without attenuating the incident light. In the light-emitting device 100, the transmission and reflection layer 19 is composed of, for example, 10 to 40 layers (5 to 20 pairs) of alternating silicon oxide (SiO2) and aluminum oxide (Al2O3).

[0063] The material used for the transmission and reflection layer 19 can be a combination of titanium dioxide (TiO2), niobium oxide (NbO), magnesium oxide (MgO), tantalum oxide (Ta2O5), hafnium oxide (HfO), etc.

[0064] In the light-emitting device 100 of this embodiment, the reflectivity of the transmissive reflective layer 19 for white light is set to 60%. As a result, the light emitted from the light-emitting device 100 has a light distribution known as a batwing light distribution, in which the light intensity is suppressed directly above the light-emitting device 100, while the light intensity is increased on the side surfaces. In other words, the light emitted from the light-emitting device 100 has a light distribution with a wider angle (half-value angle 140° to 180°) than the Lambertian light distribution (half-value angle 120°), in which the light intensity decreases from directly above the light-emitting device 100 to the side surfaces.

[0065] The light-emitting device 100 with such a batwing light distribution can be used in environments where a highly uniform luminance distribution is required over a wide range, such as a light source for auxiliary lights in vehicles or a light source for direct-lit backlights in LCD TVs.

[0066] The phosphor layer 15 of the light-emitting device 100 of this embodiment includes a frame-shaped portion 15F continuously formed around the periphery of the phosphor layer 15 as described above. For example, when the phosphor layer 15 is separated into individual light-emitting devices using a dicing device during the manufacturing of the light-emitting device 100, the manufacturing yield can be improved by processing the phosphor layer 15 so that the frame-shaped portion 15F is left (details will be described later).

[0067] [verify]

[0068] Here, use Figures 3 to 5 This section describes the details of the verification performed on the light-emitting device 100 in this embodiment and the results of the verification. Figure 5 This is a table illustrating the light output ratio, luminance distribution, and luminance ratio (minimum luminance / maximum luminance) calculated by measuring the light output and luminance of six samples A to F based on the structure of the light-emitting device 100.

[0069] exist Figure 5 In this study, each of samples B through F differs from reference sample A in the height HP of the phosphor layer 15 from the upper surface of the substrate 11 and the thickness HC of the sealing layer 17 from the upper surface of the phosphor layer 15 (see [reference]). Figure 3 and Figure 4 ( ), or the reflectivity of the transmissive reflective layer 19 to white light. The thickness of the frame portion 15F from the upper surface of the substrate 11 is defined as the thickness HR.

[0070] In this verification, a measurement module was used in which samples A through F, each measuring 1 mm square, were placed at the center of a 9 mm square white housing with an opening at the top. The white housings, each containing one sample, were arranged in a 3×3 pattern without gaps, and the light output and luminance of each sample were measured using light emitted from one of the white housings at its center.

[0071] Figure 5 The "Luminance Distribution within the Housing" table shows the luminance distribution when a white housing containing each of samples A through F is placed, viewed from above, and indicates that the darker the color, the higher the luminance. For example, in sample A, the highest luminance can be observed around the light-emitting device 100.

[0072] also, Figure 5 The "luminance ratio" in the table indicates that the closer the value is to 1, the more uniform the luminance of the light from the white shell. In other words, the higher the luminance ratio, the more uniformly the light is distributed within the white shell.

[0073] [Comparison of Sample A, Sample B, and Sample C]

[0074] The only difference between samples A, B and C is the height HP of the phosphor layer 15 (0.4 mm, 0.6 mm and 0.8 mm, respectively), while the thickness HC (0.1 mm) of the sealing layer 17 and the reflectivity (60%) of the transmission and reflection layer 19 are the same.

[0075] like Figure 5 As illustrated, compared to 100% of sample A, the light output ratio of sample B increased to 109.5%, and that of sample C increased to 108.4%. The luminance ratio also improved, from 0.748 for sample A to 0.774 for sample B and 0.772 for sample C. In other words, both the light output ratio and luminance ratio of samples B and C are better than those of sample A.

[0076] [Comparison of Sample A, Sample D, and Sample E]

[0077] The only difference between samples A, D and E is the thickness HC of the sealing layer 17 (0.1 mm, 0.3 mm and 0.5 mm, respectively), while the height HP (0.4 mm) of the phosphor layer 15 and the reflectivity (60%) of the transmission and reflection layer 19 are the same.

[0078] like Figure 5As illustrated, when sample A is set to 100%, the light output ratio of sample D is 101.7%, and that of sample E is 102.3%. However, compared to 0.748 for sample A, the luminance ratio of sample D has decreased to 0.723, and that of sample E has decreased to 0.692. In other words, while samples D and E are superior to sample A in terms of light output ratio, they are inferior to sample A in terms of luminance ratio.

[0079] [Comparison of Sample A and Sample F]

[0080] The only difference between sample A and sample F is the reflectivity of the transmission and reflection layer 19 (60% and 90%, respectively), while the height HP (0.4 mm) of the phosphor layer 15 and the thickness HC (0.1 mm) of the sealing layer 17 are the same.

[0081] like Figure 5 As illustrated, sample F has a light output ratio of 91.5%, which is lower than that of sample A (100%). Furthermore, sample F has a luminance ratio of 0.548, which is lower than that of sample A (0.748). In other words, both the light output ratio and luminance ratio of sample F are lower than those of sample A.

[0082] [Verification Summary]

[0083] Based on a comparison of samples A, B, and C, preferably, in the light-emitting device 100 having a square diameter of 1 mm, the height HP of the phosphor layer 15 from the upper surface of the substrate 11 is 0.6 mm to 0.8 mm. In other words, preferably, the height HP of the phosphor layer 15 is 60% to 80% of the length of one side of the transmission-reflection layer 19 when the light-emitting device 100 is viewed from above.

[0084] Furthermore, based on the comparison results of samples A, D, and E, for a light-emitting device 100 with a square diameter of 1 mm, from the perspective of achieving a wide-angle light distribution using the light-emitting device 100, the thickness HC of the sealing layer 17 from the upper surface of the phosphor layer 15 is preferably 0.1 mm. In other words, preferably, the thickness HC of the phosphor layer 15 is 10% of the length of one side of the transmission and reflection layer 19 when the light-emitting device 100 is viewed from above.

[0085] Furthermore, based on the comparison results of samples A and F, in the light-emitting device 100 having a square diameter of 1 mm, the reflectivity of the transmission-reflection layer 19 for white light is preferably 60%. When the reflectivity of the transmission-reflection layer 19 decreases to below 50%, the central luminance of the white housing increases, and the luminance ratio decreases. Similarly, when the reflectivity of the transmission-reflection layer 19 exceeds 70%, the central luminance of the white housing decreases, and the luminance ratio decreases. In other words, the reflectivity of the transmission-reflection layer 19 is preferably 60 ± 10%, and more preferably 60 ± 5%.

[0086] As described above, the light-emitting device 100 of this embodiment can emit light with a wide-angle light distribution.

[0087] In this embodiment, it is described that the light emitted from the light-emitting device 100 has a batwing light distribution. However, it is sufficient for the light emitted from the light-emitting device 100 to have a wide-angle light distribution, and it is not necessary to have a batwing light distribution.

[0088] For example, the reflectivity of the transmissive and reflective layer 19 in the light-emitting device 100 to white light can be made less than 60%. This makes it possible to obtain an umbrella-shaped light distribution, or so-called umbrella-shaped light distribution, as a whole by increasing the light output from directly above the light-emitting device 100 compared to a batwing light distribution and then gradually decreasing it as it moves to the side.

[0089] [Variation of the light-emitting device 100]

[0090] Next, a variation of Embodiment 1 will be described. In this modification, the configuration of the transmission and reflection layer 19 differs from that in Embodiment 1, but the configuration of other parts (e.g., the phosphor layer 15 and the sealing layer 17) is the same as in Embodiment 1.

[0091] In this variant, the transmission-reflection layer 19 is constructed by dispersing yttrium phosphate (YPO4) particles with a particle diameter of 1 nm to 5 nm in a silicone resin. The YPO4 particles have weaker backscattering properties than titanium dioxide (TiO2) particles or aluminum oxide (Al2O3) particles, which scatter light in the opposite direction to the incident direction, and have excellent forward scattering properties, which scatter light in the same direction as the incident direction of the light.

[0092] Therefore, the white light entering the transmissive and reflective layer 19 of the variant from the sealing layer 17 in the outward direction along the transmissive and reflective layer 19 ( Figure 3 and Figure 4 The light is emitted after being widely scattered (at the top direction). In addition, while suppressing the attenuation of light within the transmission and reflection layer 19 due to backscattering, a so-called reverse umbrella-shaped light distribution can be generated, which is a reverse triangular light distribution that increases the light output of the central part of the bat wing light distribution or bat wing light distribution.

[0093] Even when the configuration of the transmissive reflective layer 19 is changed in this way, the light-emitting device 100 of this variant can emit light with a wide-angle light distribution similar to the light-emitting device 100 of Embodiment 1.

[0094] [Manufacturing method of the first light-emitting device 100]

[0095] The following uses Figures 6 to 10 The first manufacturing method of the light-emitting device 100 is described. Figures 6 to 10 This is a cross-sectional view illustrating the steps of a first manufacturing method for the light-emitting device 100. As an example, Figures 6 to 10 A partial cross-sectional view of a substrate assembly 11M having a plurality of light-emitting elements 13 disposed on its upper surface is shown.

[0096] First, prepare a substrate assembly 11M with various wiring patterns (Step 1: Substrate Preparation Steps). Specifically, as follows... Figure 6 As shown, a substrate assembly 11M is prepared. In the substrate assembly 11M, before the anode pad 21 and cathode pad 22 are formed (before cutting), a pad body PM is patterned on its upper surface, an anode electrode 23 and a cathode electrode 24 are patterned on its lower surface, and a through hole 25 is formed to electrically connect the pad body PM to the anode electrode 23 and the cathode electrode 24.

[0097] Subsequently, as Figure 6 As illustrated, multiple light-emitting elements 13 are mounted on the upper surface of the substrate assembly 11M (Step 2: Component Mounting Step). Specifically, epoxy resin solder 33 is applied to the pad body PM, and the light-emitting elements 13 are placed on the applied epoxy resin solder 33. Then, the light-emitting elements 13 are mechanically and electrically bonded to the pad body PM by heating the light-emitting elements 13 at 250°C for 0.5 minutes and then holding them at 150°C for 2 hours.

[0098] Next, a phosphor layer 15M is formed on the substrate assembly 11M to surround the plurality of light-emitting elements 13 (step 3: phosphor layer formation step). Specifically, as shown in... Figure 7 As illustrated, a frame-shaped first dam structure D1 made of resin is formed on the upper surface of the substrate assembly 11M along the outer edge of the substrate assembly 11M, and a predetermined amount of first precursor resin, which serves as the phosphor layer 15M, is poured into the first dam structure D1. The first precursor resin is then allowed to settle to smooth it, and the phosphor layer 15M is formed by heating at 150°C and curing for 120 minutes. The method of pouring the precursor resin into the dam structure and then thermosetting the precursor resin is referred to as "pouring and molding".

[0099] Next, separation trenches are formed on the upper surface of the phosphor layer 15M, separating the substrate assembly 11M into individual light-emitting elements 13 in a top view (step 4: trench formation step). Specifically, as... Figure 8 exemplified using Figure 7 The dicing blade BL1 of the dicing device shown forms a separation groove 15MG to separate the individual light-emitting elements in the plurality of light-emitting elements 13.

[0100] At this point, separation trenches 15MG are formed, leaving a remaining portion with a thickness of HR on the upper surface of the substrate assembly 11M. The aforementioned frame-shaped portion 15F of the light-emitting device 100 is the remaining portion of these separation trenches 15MG. The remaining portion is configured such that the wide cutting edge of the dicing blade BL1 does not contact the upper surface of the substrate assembly 11M. This is because the wide cutting edge of the dicing blade BL1 causes the substrate assembly 11M to bend, resulting in the peeling of the phosphor layer 15 or the breakage of the light-emitting element 13.

[0101] Next, a sealing layer 17M covering the phosphor layer 15M is formed by casting and molding (step 5: sealing layer formation step). Specifically, as shown... Figure 9 As illustrated, a frame-shaped second dam structure D2 made of resin is formed along the outer edge of the substrate assembly 11M to surround the first dam structure D1, and a predetermined amount of second precursor resin, which serves as a sealing layer 17M, is poured into the second dam structure D2.

[0102] This allows the second precursor resin to fill the separation grooves 15MG of the phosphor layer 15M. The second precursor resin is then allowed to settle to smooth it, and then a sealing layer 17M is formed by heating and curing at 150°C for 120 minutes.

[0103] Next, a transmission and reflection layer 19M, serving as a dielectric multilayer film, is formed on the upper surface of the sealing layer 17M (step 6: transmission and reflection layer formation step). Specifically, as... Figure 10 As illustrated, the transmissive and reflective layer 19M is formed by alternating stacking of Al2O3 and SiO2 layers through atomic layer deposition (ALD), resulting in a reflectivity of approximately 60% for white light.

[0104] Finally, each of the multiple light-emitting devices 100 is individualized (step 7: individualization step). Specifically, by using... Figure 10 The dicing blade BL2 of the dicing device illustrated cuts along the separation groove 15MG from the top of the transmission and reflection layer 19M to the substrate assembly 11M, individualizing each of the multiple light-emitting devices 100. The light-emitting devices 100 can be manufactured by the above steps.

[0105] In step 7, the dicing blade BL2 used to individualize the light-emitting device 100 has a thinner blade than the dicing blade BL1 used in step 4 to form the separation groove 15MG.

[0106] Therefore, when the light-emitting device 100 is individualized using the dicing blade BL2, the force applied to the substrate assembly 11M is reduced. Thus, the substrate assembly 11M can be cut without bending it.

[0107] In step 4 above, the thickness HR of the remaining phosphor layer 15M when the separation trench 15MG is formed (later, the frame portion 15F) is preferably greater than the value (D+σ) obtained by adding the standard deviation (σ) to the average particle size (D) of the larger phosphor particles contained in the phosphor layer 15M.

[0108] For example, the average particle size of the β-thion phosphor is 16 μm, which is larger than the average particle size (D) of the KSF phosphor, and the standard deviation (σ) is 5 μm. Therefore, preferably, the thickness HR is 21 μm or more. Furthermore, more preferably, it is 26 μm (D + 2σ), that is, the average particle size (D) plus twice the standard deviation (σ), and even more preferably, it is 31 μm (D + 3σ), that is, the average particle size (D) plus three times the standard deviation (σ).

[0109] This is because during the formation of the separation trench 15MG, phosphor particles are trapped between the wide cutting edge of the dicing blade BL1 and the upper surface of the substrate assembly 11M, and this suppresses the formation of cracks in the substrate assembly 11M due to the trapped phosphor particles. Furthermore, it suppresses the problem of the second precursor resin, serving as the sealing layer 17M, covering the anode electrode 23 and cathode electrode 24 on the bottom surface through cracks in the substrate assembly 11M during step 5 (sealing layer formation step).

[0110] If the separation trench 15MG is shallow, the exposed cross-section of the frame portion 15F increases during the manufacture of the light-emitting device 100, and the phosphor contained in the phosphor layer 15 may deteriorate due to corrosive gases in the external air. Therefore, preferably, the thickness HR is less than 1 / 8 of the height HP of the phosphor layer 15. More preferably, it is less than 1 / 16 of the height HP.

[0111] For example, when the height of the phosphor layer 15 is 0.6 mm, the thickness HR is preferably 0.075 mm (75 μm) or less, and more preferably 0.038 mm (38 μm). Furthermore, when the height of the phosphor layer 15 is 0.8 mm, the thickness HR is preferably 0.1 mm (100 μm) or less, and more preferably 0.05 mm (50 μm).

[0112] [Improving yield rates in the manufacturing of light-emitting devices]

[0113] As described above, in the manufacturing method of the light-emitting device 100 of this embodiment, when forming the separation trench 15MG in step 4, by not cutting a portion of the phosphor layer 15, it is possible to suppress the peeling of the phosphor layer 15M from the substrate assembly 11M and the disconnection of the light-emitting element 13. In other words, this improves the yield during the manufacturing process. Furthermore, since the formation of cracks in the substrate assembly 11M in step 4 is suppressed, the anode electrode 23 and cathode electrode 24 are prevented from being covered by the resin of the sealing layer 17M during the formation of the sealing layer 17M in step 5. This also improves the yield during the manufacturing process.

[0114] Therefore, in the first manufacturing method of the light-emitting device 100 of this embodiment, the substrate assembly 11M becomes less prone to bending or breaking. Thus, the first manufacturing method of the light-emitting device 100 of this embodiment can improve the yield rate during manufacturing of the light-emitting device 100.

[0115] [Manufacturing method of the light-emitting device 100 according to a variant example]

[0116] Next, a method for manufacturing the light-emitting device 100 according to this variant will be described. The only difference between the manufacturing method of the light-emitting device 100 of this variant and the first manufacturing method described above is step 6 (the step of forming the transmission and reflection layer), while in other respects it is the same as the first manufacturing method.

[0117] In this manufacturing method, the transmissive and reflective layer 19M is formed on the upper surface of the sealing layer 17M by casting and molding. Specifically, a frame-shaped third dam structure D3 (not shown) made of resin is formed along the outer edge of the substrate assembly 11M to surround the second dam structure D2, and a predetermined amount of third precursor resin (which is silicone resin in which YPO4 particles are dispersed) is cast into the third dam structure D3. After the third precursor resin is allowed to settle to make it smooth, it is thermocured at 150°C for 90 minutes to form the transmissive and reflective layer 19M of the light-emitting device 100 according to this variant.

[0118] In this manufacturing method, since the manufacturing steps 4 and 5 described above are not affected, the yield of manufacturing the light-emitting device 100 can be improved, and the phosphor layer 15M, the sealing layer 17M, and the transmission and reflection layer 19M can be formed by casting and molding methods.

[0119] [Manufacturing method of the second light-emitting device 100]

[0120] Subsequently, using Figures 11 to 14A second manufacturing method for the light-emitting device 100 is described. The second manufacturing method differs from the first manufacturing method in that insert molding is used to perform steps 3 (phosphor layer formation step), 5 (sealing layer formation step), and 6 (transmission and reflection layer formation step) described in the first manufacturing method, while the other steps are the same as those in the first manufacturing method.

[0121] The following describes each step that differs from steps 3, 5 and 6 of the first manufacturing method, referred to as steps 3-2, 5-2 and 6-2 respectively.

[0122] [Step 3-2: Formation of the phosphor layer]

[0123] In the phosphor layer formation process of this manufacturing method, such as Figure 11 As illustrated, a substrate assembly 11M on which light-emitting elements 13 are mounted is clamped by a first mold 41 consisting of an upper mold 41U and a lower mold 41L. The upper mold 41U has a first space SP1 on the upper surface of the substrate assembly 11M that accommodates a plurality of light-emitting elements 13.

[0124] Then, as Figure 12 As illustrated, the first precursor resin is poured into the first space SP1 formed by the first mold 41. Then, the first precursor resin is cured by heating the first mold 41 to a curing temperature to form the phosphor layer 15M.

[0125] [Step 5-2: Sealing Layer Formation Step]

[0126] In the sealing layer forming step of this manufacturing method, such as Figure 13 As illustrated, a substrate assembly 11M having a phosphor layer 15M and separation trenches 15MG is sandwiched by a second mold 42 consisting of an upper mold 42U and a lower mold 42L. The upper mold 42U has a second space SP2 that accommodates the phosphor layer 15M on the upper surface of the substrate assembly 11M.

[0127] Then, as Figure 13 As illustrated, the aforementioned second precursor resin is poured into the second space SP2 formed by the second mold 42. Then, the second precursor resin is cured by heating the second mold 42 to a curing temperature to form a sealing layer 17M.

[0128] [Step 6-2: Formation of the Transmission-Reflection Layer]

[0129] In the transmission and reflection layer formation step of this manufacturing method, such as Figure 14As illustrated, the substrate assembly 11M, on which the sealing layer 17M is formed, is sandwiched by a third mold 43 consisting of an upper mold 43U and a lower mold 43L. The upper mold 43U has a third space SP3 that accommodates the sealing layer 17M on the upper surface of the substrate assembly 11M.

[0130] Then, as Figure 14 As illustrated, the third precursor resin described in the variant example is poured into the third space SP3 formed by the third mold 43. Then, the third precursor resin is cured by heating the third mold 43 to a curing temperature to form the transmissive reflective layer 19M.

[0131] Each of steps 3-2, 5-2, and 6-2 in the second manufacturing method forms each layer by so-called insert molding (specifically, transfer molding or compression molding). Thus, compared to the first manufacturing method, it is possible to stably mass-produce the light-emitting device 100 with high shape accuracy and high manufacturing productivity.

[0132] Furthermore, in the second manufacturing method, step 4 can be provided between steps 3-2 and 5-2, which improves the yield when manufacturing the light-emitting device 100. Specifically, in step 5-2 of insert molding, high-pressure second precursor resin is injected onto the upper surface of the substrate assembly 11M on which the phosphor layer 15M and separation trenches 15MG have already been formed. Therefore, the yield during manufacturing can be improved by step 4, in which the separation trenches 15MG are formed without causing cracks in the substrate assembly 11M.

[0133] [Third manufacturing method for the light-emitting device 100]

[0134] Next, a third manufacturing method for the light-emitting device 100 will be described. The third manufacturing method is a manufacturing method in which a portion of the steps described in the first manufacturing method are replaced with steps of the second manufacturing method. Specifically, for steps 1 to 3, 6 and 7, the third manufacturing method is the same as the first manufacturing method, except that step 5 (the sealing layer forming step) is replaced with step 5-2 of the second manufacturing method.

[0135] The second precursor resin used to form the sealing layer 17M in step 5 is a liquid containing no solids. Therefore, it is suitable for insert molding. Furthermore, since the upper surface of the sealing layer 17M formed by insert molding is a highly precise flat surface, it is suitable for forming a transmission and reflection layer 19M as a dielectric multilayer film.

[0136] In other words, in the third manufacturing method, the phosphor layer 15M is formed by casting and molding, the sealing layer 17M is formed by insert molding, and the transmission and reflection layer 19M is formed by ALD molding.

[0137] The third manufacturing method combines the casting and molding of the first manufacturing method with the insert molding of the second manufacturing method. Therefore, the third manufacturing method of the light-emitting device 100 can achieve stable mass production while suppressing manufacturing deviations of the light-emitting device 100. In other words, compared with the first and second manufacturing methods, the third manufacturing method of the light-emitting device 100 improves the balance between manufacturing accuracy and cost.

[0138] In other words, the third manufacturing method is suitable for forming the phosphor layer 15M, the sealing layer 17M, and the transmission and reflection layer 19M, and since high yield can be achieved for each manufacturing step, the yield of manufacturing the light-emitting device 100 can be improved.

[0139] When the light-emitting device 100 is individualized in step 7 as described above, it can be cut from the underside of the substrate assembly 11M using a dicing blade BL2. In this case, the cutting with the dicing blade BL2 is performed using the anode electrode 23 and cathode electrode 24 formed on the underside of the substrate assembly 11M as markers, which reduces the variation in the external dimensions of the light-emitting device 100.

[0140] As described in the above embodiments, by using the present invention, the yield of the light-emitting device 100 can be improved in the manufacturing process while achieving a wide-angle light distribution of the emitted light of the light-emitting device 100.

[0141] Explanation of reference numerals in the attached figures

[0142] 11 substrate

[0143] 13 light-emitting elements

[0144] 15 fluorophores

[0145] 17 sealing layers

[0146] 19 Transmission and Reflection Layers

[0147] 21 Anode Pads

[0148] 22 Cathode Pads

[0149] 23 Anode electrode

[0150] 24 Cathode Electrode

[0151] 25 through hole

[0152] 27 Semiconductor Structure Layers

[0153] 28 Transparent Substrate

[0154] 31 p electrode

[0155] 32 n electrode

[0156] 33 Epoxy Resin Solder

Claims

1. A semiconductor light-emitting device, the semiconductor light-emitting device comprising: substrate; A light-emitting element, the light-emitting element comprising a light-emitting layer made of semiconductor disposed on a main surface of the substrate; A phosphor layer is formed on a main surface to cover the light-emitting element. The phosphor layer has a frame-like portion that protrudes laterally from the lower end of a side surface along the main surface and is continuously formed around the periphery of the phosphor layer in a top view. The phosphor layer has phosphor particles that emit fluorescence when excited by light emitted from the light-emitting layer. A light-transmitting sealing layer covers the upper surface of the phosphor layer, extends from the upper end of the side surface to cover the side surface, and terminates at the upper surface of the frame-shaped portion; as well as A transmissive reflective layer is formed on the upper surface of the sealing layer to partially reflect and partially transmit each of the light emitted from the light-emitting layer and the fluorescence emitted from the phosphor layer.

2. The semiconductor light-emitting device according to claim 1, wherein... The semiconductor light-emitting device has a half-value angle wider than that of the Lambertian light distribution.

3. The semiconductor light-emitting device according to claim 2, wherein... The reflectivity of the transmissive and reflective layer to the light and the fluorescence is 60 ± 10%.

4. The semiconductor light-emitting device according to claim 1, wherein... The transmission and reflection layer is composed of a dielectric multilayer film.

5. The semiconductor light-emitting device according to claim 1, wherein... The transmission and reflection layer is composed of a transparent silicone resin in which yttrium phosphate particles are dispersed.

6. The semiconductor light-emitting device according to any one of claims 1 to 5, wherein The phosphor layer contains at least one phosphor that emits red fluorescence when excited by light emitted from the light-emitting layer.

7. The semiconductor light-emitting device according to any one of claims 1 to 5, wherein The height of the phosphor layer from the main surface is 60% to 80% of the length of one side of the transmissive and reflective layer when the semiconductor light-emitting device is viewed from above.

8. The semiconductor light-emitting device according to any one of claims 1 to 5, wherein The thickness of the frame-shaped portion is above the value obtained by adding the standard deviation to the average particle size of the phosphor particles, and below 1 / 8 of the thickness of the phosphor layer.

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