Semiconductor light emitting device and manufacturing method thereof

Abstract

The invention provides a semiconductor light emitting device and a manufacturing method thereof. The phosphor plate and the light-emitting element can be bonded in the atmosphere by surface activation bonding. The semiconductor light-emitting device includes a light-emitting element including a semiconductor light-emitting layer, and a phosphor plate bonded to the light-emitting element. Between the light-emitting element and the phosphor plate, a buffer layer comprising a dielectric that transmits light emitted by the light-emitting element is disposed. The light-emitting element and the phosphor plate are bonded via a buffer layer. The buffer layer is amorphous.

Description

Technical Field

[0001] The present invention relates to a semiconductor light emitting device having a structure in which a semiconductor light emitting element and a phosphor plate are directly bonded without interposing a resin adhesive layer or the like. Background Art

[0002] Patent Documents 1 and 2 disclose methods for manufacturing a light-emitting device in which a phosphor plate is directly bonded to a light-emitting element by surface activated bonding (SAB) without using an adhesive. The light-emitting device manufactured by these manufacturing methods does not include an adhesive layer having a refractive index different from that of the light-emitting element or the phosphor plate (particularly an adhesive layer having a refractive index lower than that of the light-emitting element or the phosphor plate), thereby improving the light extraction efficiency from the light-emitting device.

[0003] Specifically, in the manufacturing method of Patent Document 1, the pre-singulated light-emitting elements are arranged on a relay substrate, and the bonding surfaces of the light-emitting elements and the phosphor ceramics are polished respectively, and then placed in a vacuum device. In the vacuum device, after irradiating each bonding surface with an ion beam of a rare gas element (at least one of He, Ne, Ar, and Kr), the bonding surfaces are brought into contact with each other and pressurized, thereby bonding. After the bonded light-emitting elements and phosphor ceramics are taken out of the vacuum device, the phosphor ceramics are cut into individual pieces for each light-emitting device by dicing.

[0004] On the other hand, Patent Document 2 discloses the following method: after directly bonding the substrate of the light-emitting element to the phosphor plate by surface activation bonding, both the light-emitting element and the phosphor plate are cut for each light-emitting device, thereby manufacturing individual light-emitting devices. This manufacturing method bonds an element substrate formed with a plurality of light-emitting elements to a phosphor plate by surface activation bonding. Before bonding, the element substrate is thinned by grinding and polishing, and a laser is irradiated to a position of the thinned element substrate that becomes a boundary between elements to form a crack. The phosphor plate is brought into contact with the element substrate formed with the crack, and bonded by surface activation bonding by applying pressure. Then, the phosphor plate is cut to the middle of the thickness of the phosphor plate by a blade. The position that becomes the boundary between elements is pressed from the light-emitting element side, and the element substrate is cut due to the crack, and at the same time, the semiconductor structure of the light-emitting element without the crack, the wiring structure, and the uncut portion of the phosphor plate are also cut to be singulated.

[0005] Prior art literature

[0006] Patent Literature

[0007] [Patent Document 1] Japanese Patent Application Publication No. 2019-220675

[0008] [Patent Document 2] Japanese Patent Application Publication No. 2021-197542 Summary of the invention

[0009] Problems to be solved by the invention

[0010] The manufacturing method of Patent Document 1 irradiates the bonding surface of the light-emitting element and the phosphor ceramic with an ion beam of a rare gas element to perform surface treatment, so it is necessary to arrange the light-emitting element and the phosphor ceramic in a vacuum device. After irradiation with the ion beam, the vacuum device is not opened to the atmosphere, and the bonding surface of the light-emitting element and the phosphor ceramic is brought into contact and bonded in a vacuum. Therefore, it is necessary to perform all operations such as surface activation treatment, alignment, substrate heating, and substrate weighting in a vacuum, which complicates the device structure and increases the price of the device, thereby increasing the cost of the product.

[0011] In addition, in the manufacturing method of Patent Document 1, the light-emitting elements are pre-monolithized and arranged, and after the phosphor ceramic is activated and bonded on the upper surface, the phosphor ceramic is cut and monolithicized for each light-emitting device. Therefore, the monolithic light-emitting device also has the problem that the size of the phosphor ceramic is inevitably larger than the light-emitting element.

[0012] On the other hand, although the manufacturing method of Patent Document 2 does not pre-single the light emitting element, a crack is introduced in the element substrate by laser in advance in order to cut the element substrate later, so the strength of the element substrate is reduced. Therefore, when the phosphor plate is brought into contact with the element substrate and pressurized for surface activation bonding, it is necessary to limit the pressurizing load in order to prevent the element substrate from cracking.

[0013] In addition, in the process after bonding the element substrate and the phosphor plate, the element substrate may be broken due to internal stress, external stress, etc. If the element substrate is warped or external force is applied, the element substrate and the phosphor plate may be separated at the bonding surface.

[0014] An object of the present invention is to provide a semiconductor light emitting device in which a phosphor plate and a light emitting element are bonded with high reliability by surface activated bonding.

[0015] Means for solving problems

[0016] In order to achieve the above-mentioned object, the semiconductor light-emitting device of the present invention comprises a light-emitting element including a semiconductor light-emitting layer and a phosphor plate bonded to the light-emitting element. A buffer layer composed of a dielectric material is arranged between the light-emitting element and the phosphor plate so as to transmit the light emitted by the light-emitting element. The light-emitting element and the phosphor plate are bonded via the buffer layer. The buffer layer is amorphous.

[0017] Effects of the Invention

[0018] According to the semiconductor light emitting device of the present invention, the bonding reliability between the phosphor plate and the light emitting element can be improved by surface activated bonding. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 (a) and (b) are a cross-sectional view and a top view of the semiconductor light emitting device according to the first embodiment.

[0020] Figure 2 (a) to (g) are explanatory diagrams showing the manufacturing process of the semiconductor light emitting device according to the first embodiment.

[0021] Figure 3 (a) to (e) are explanatory diagrams showing the manufacturing process of the semiconductor light emitting device according to the first embodiment.

[0022] Figure 4 Yes means Figure 3 (c) is a cross-sectional view of the shape of the stacked body after the manufacturing step.

[0023] Figure 5 (a) to (e) show the first embodiment. Figure 3 FIG. 2 is a diagram showing an example of the cross-sectional shape of the cutout 110 formed in the step (b).

[0024] Figure 6 (a) and (b) are a cross-sectional view and a plan view of a semiconductor light emitting device according to a modification of the first embodiment.

[0025] Figure 7 It is a cross-sectional view of a semiconductor light emitting device according to a second embodiment.

[0026] Figure 8 (a) to (g) are explanatory diagrams showing the manufacturing process of the semiconductor light emitting device according to the second embodiment.

[0027] Fig. 9 (a) to (e) are explanatory diagrams showing the manufacturing process of the semiconductor light emitting device according to the second embodiment.

[0028] Fig.10 (a) to (j) are explanatory diagrams showing the manufacturing process of the semiconductor light emitting device according to the third embodiment.

[0029] Fig.11 It is a cross-sectional view of a semiconductor light emitting device according to a fourth embodiment.

[0030] Fig.12 (a) to (i) are explanatory diagrams showing the manufacturing process of the semiconductor light emitting device according to the fourth embodiment.

[0031] Fig.13(h-1), (h-2) and (i) are explanatory diagrams showing another example of the manufacturing process of the semiconductor light emitting device according to the fourth embodiment. DETAILED DESCRIPTION

[0032] Embodiments of the present invention will be described below.

[0033] <<First embodiment>>

[0034] use Figure 1 to Figure 4 A semiconductor light emitting device according to a first embodiment will be described. Figure 1 (a) and (b) are a cross-sectional view and a plan view of the semiconductor light emitting device 1 according to the first embodiment.

[0035] like Figure 1 As shown in (a) of FIG. 1 , the semiconductor light emitting device 1 of the present embodiment has a structure in which a phosphor plate 20 is bonded to the upper surface of a light emitting element 10 by surface activated bonding (SAB). Figure 1 In the semiconductor light emitting device 1 of (a), the light emitting element 10 is a flip chip type light emitting element, and the light emitting element 10 is composed of a semiconductor light emitting layer 12, an element substrate 11 arranged on the upper surface thereof, and a pair of electrodes 13 arranged on the lower surface of the semiconductor light emitting layer 12. A phosphor plate 20 is bonded to the upper surface of the element substrate 11.

[0036] A buffer layer 21 is disposed on the bonding surface between the element substrate 11 and the phosphor plate 20. In addition, a part of the side surface of the light-emitting element 10, the buffer layer 21, and the phosphor plate 20 is formed by cutting, and another part is formed by cleaving, but there is no sharp angle, but a smooth shape, and it is covered with the light-reflective multilayer film 40. In addition, the light-reflective multilayer film 40 may not be provided. In addition, instead of forming the light-reflective multilayer film 40, a structure in which the side surface is covered with a light-reflective resin may be adopted.

[0037] exist Figure 1 In the examples (a) and (b) of FIG. 1 , the semiconductor light emitting device 1 is mounted on a wiring substrate 30 including a pair of wirings 32 and a substrate 31 , and a pair of electrodes 13 of the light emitting element 10 is electrically connected to the pair of wirings 32 .

[0038] As the light emitting element 10 , for example, a blue LED can be used in which the element substrate 11 is a sapphire substrate, a spinel substrate, or a GaN substrate, and the semiconductor light emitting layer 12 includes a GaN layer.

[0039] The phosphor plate 20 absorbs a part of the light emitted from the semiconductor light emitting layer 12 and emits fluorescence of a predetermined wavelength, thereby converting the wavelength of the light emitted from the semiconductor light emitting layer 12 and emitting the light from the upper surface.

[0040] The phosphor plate 20 is made of, for example, YAG (Y3Al5O 12 ) is composed of a composite ceramic phosphor plate (Al2O3 / Ce:YAG) of phosphor particles. In addition, the phosphor plate 20 is not limited to the composite ceramic phosphor plate (Al2O3 / Ce:YAG), and a phosphor plate composed of a single crystal of Ce:YAG, a phosphor ceramic plate of YAG matrix (YAG / Ce:YAG) or glass can be used. In addition, in the composite ceramic phosphor plate, the particle size and density of the YAG particles can also be appropriately selected according to the application.

[0041] Surface activated bonding utilizes the intermolecular forces of the substances on both sides of the bonding surface for bonding, and the distance between the molecules of the substances on both sides of the bonding surface needs to be a distance at which the intermolecular forces act (≤ 0.5 nm). Therefore, in order to bond the phosphor plate 20 and the element substrate 11 by surface activated bonding, the surfaces of the phosphor plate 20 and the element substrate 11 need to be flattened to a roughness below the distance at which the intermolecular forces act (≤ 0.5 nm).

[0042] The composite ceramic phosphor plate constituting the phosphor plate 20 is composed of microcrystalline grains, and the hardness of the microcrystalline grains of the ceramic matrix and the microcrystalline grains of the phosphor are different. In addition, the hardness of the microcrystalline also varies depending on the direction in which the crystal axis of the microcrystalline is oriented in the phosphor plate 20. Therefore, even if the phosphor plate 20 is ground, a height difference (roughness) of about 1 / 20 of the particle size of the abrasive grains of the slurry used for grinding will remain on the surface.

[0043] Specifically, for example, in the case of a phosphor plate 20 of a composite ceramic phosphor plate (Al2O3 / Ce:YAG), when mirror polishing is performed using a slurry containing 1μm diamond particles as abrasives, due to the difference in hardness between Al2O3 and YAG, a height difference of about 50nm remains at the boundary of their grains. In addition, the matrix and phosphor particles of a YAG-based Ce:YAG phosphor plate (a plate in which YAG phosphor particles doped with Ce are dispersed in a YAG ceramic matrix) are ceramics of the same chemical formula, but due to the presence of microcrystals, even when polishing is performed using a slurry containing 50nm diamond particles as abrasives by CMP (chemical mechanical polishing) method, a surface height difference of about ±2nm (roughness Ra ~ 1.5nm) remains. Therefore, it is difficult to flatten the surface of the phosphor plate 20 to a roughness below the distance (~0.5nm or less) at which intermolecular forces act separately.

[0044] Therefore, in this embodiment, a buffer layer 21 is arranged on the phosphor plate 20, the light-emitting element 10, and the bonding surface of the phosphor plate 20. The buffer layer 21 is an amorphous layer of a dielectric. The amorphous layer can be flattened to a roughness below the distance (~0.5nm or less) at which the intermolecular force acts by grinding or the like. Therefore, by arranging the amorphous buffer layer 21 at least on the lower surface of the phosphor plate 20, it can be easily bonded to the light-emitting element 10 by surface activated bonding.

[0045] The buffer layer 21 of the amorphous layer may be provided not only on the lower surface of the phosphor plate 20 but also on both the upper surface of the element substrate 11. Alternatively, the buffer layer 21 may be provided only on the element substrate 11.

[0046] The amorphous buffer layer 21 mentioned here refers to a buffer layer that does not show a diffraction peak in the X-ray diffraction diagram when measuring X-ray diffraction. However, in principle, the amorphous buffer layer 21 does not show a diffraction peak originating from the crystal in the X-ray diffraction, but it is allowed to show a peak caused by microcrystalline grains generated at the interface between the buffer layer 21 and the base layer when the buffer layer 21 is formed. In this case, the volume ratio of the amorphous phase in the amorphous buffer layer 21 to the entire layer is also preferably 90% or more.

[0047] The buffer layer 21 preferably transmits the light emitted by the light emitting element 10 , and particularly preferably has no light absorption in the entire white spectrum region.

[0048] In addition, the buffer layer 21 can be any material as long as the thermal expansion coefficient and refractive index are close to those of the phosphor plate 20 and the light-emitting element 10 as the joined parts, the thermal conductivity is excellent when made into a thin film, the acid and alkali resistance is good, the stress corrosion is less, and the inorganic material can be flattened by grinding to a roughness below the distance where the intermolecular force acts (~0.5nm or less). In addition, the buffer layer 21 preferably has a high Young's modulus (hardness) to a certain extent.

[0049] For example, the buffer layer 21 can preferably use inorganic transparent dielectric materials such as oxides containing Al (aluminum oxide, Al2O3, etc.), silicon oxide (SiO2, etc.), niobium oxide (Nb2O5, etc.), tantalum oxide (Ta2O5, etc.), titanium oxide (TiO2, etc.), yttrium oxide (Y2O3, etc.), magnesium oxide (MgO, etc.), and zirconium oxide (ZrO2, etc.) as the material. In particular, oxides containing Al (Al2O3, etc.) have thermal expansion coefficients and refractive indices close to those of the phosphor plate 20 and the light-emitting element 10, have high thermal conductivity when made into thin films, and are not easily corroded, and are therefore suitable as the buffer layer 21.

[0050] The reason why the thermal expansion coefficient of the buffer layer 21 is preferably close to that of the joined component is that if the difference in thermal expansion coefficient between the joined component and the buffer layer is large, the strain when returning to room temperature after joining becomes large. Compared with silicon oxide (SiO2, etc.), the difference in thermal expansion coefficient between aluminum oxide (Al2O3, etc.) and the joined component is small, so the joining strain in the use environment is small, and the resistance to the change in the ambient temperature (thermal shock) of the joint portion is high.

[0051] When the thermal conductivity of the buffer layer 21 is higher, the heat generated by the phosphor plate 20 can be further dissipated to the outside through the light-emitting element 10 and the mounting substrate, so it is preferred. Compared with silicon oxide (SiO2, etc.), aluminum oxide (Al2O3, etc.) has a higher thermal conductivity and can be expected to have a high heat dissipation effect.

[0052] In addition, it is preferred that the refractive index of the buffer layer 21 is close to or greater than the refractive index of the element substrate 11. The blue light emitted from the light emitting element 10 is incident on the phosphor plate 20 via the element substrate 11 (e.g., sapphire substrate, refractive index of 1.76). At this time, when the buffer layer 21 sandwiched between the element substrate 11 and the phosphor plate 20 has a low refractive index, the light incident on the interface between the element substrate 11 and the buffer layer 21 at a large incident angle is totally reflected and sealed into the element substrate 11. Therefore, it is beneficial for light extraction that the refractive index of the buffer layer 21 is as close as possible to the refractive index of the element substrate 11, or greater than the refractive index of the element substrate 11. Compared with SiO2 (refractive index of 1.46), the refractive index of Al2O3 (refractive index of 1.64) is closer to the element substrate 11, and when used as a buffer layer 21, the light extraction efficiency can be improved.

[0053] The buffer layer 21 preferably has a Young's modulus (hardness) that is high to a certain extent. This is because if the Young's modulus is too low, there is a concern that the buffer layer 21 itself may be damaged. For example, the Young's modulus is preferably above about 50 GPa, but the higher the Young's modulus, the better, provided that the surface flatness is satisfied. The Young's modulus of Al2O3 is higher than that of SiO2 (Al2O3 is 112 GPa, SiO2 is 50 GPa), and when used as a buffer layer 21, high bonding reliability can be obtained.

[0054] In addition, when alumina (Al2O3, etc.) is used as the material of the buffer layer 21, and a composite ceramic phosphor plate (Al2O3 / Ce:YAG) in which Ce-doped YAG phosphor particles are dispersed in an alumina ceramic matrix is ​​used as the phosphor plate 20, the buffer layer 21 is made of the same material as Al2O3, which is the base material of the phosphor plate 20, so that the effect of high interface bonding strength can also be obtained. That is, in the area where the base material of the phosphor plate 20 and the buffer layer 21 are in contact, they are bonded in the same manner and have the same thermal expansion coefficient, so there is no residual stress after bonding, and thus stable bonding can be achieved.

[0055] In addition, when alumina (Al2O3, etc.) is used as the material of the buffer layer 21 and sapphire (Al2O3) is used as the element substrate 11, since it is the same type of bonding, the thermal expansion coefficient is the same, so there is no residual stress after bonding, and stable bonding can be achieved.

[0056] Therefore, the element substrate 11 , the buffer layer 21 , and the phosphor plate 20 can be stably bonded by the same type of bonding.

[0057] The thickness of the amorphous buffer layer 21 can be any thickness as long as it can cover the unevenness of the phosphor plate 20 or the light-emitting element 10 and can make the surface of the buffer layer 21 flat to a roughness below the distance (~0.5nm or less) at which the intermolecular force acts by grinding, etc. Specifically, the thickness of the buffer layer 21 is preferably, for example, 50nm to 2μm, and particularly preferably about 200nm to 600nm.

[0058] The amorphous buffer layer 21 can be formed by physical vapor deposition methods such as EB (electron beam) vapor deposition and sputtering methods that heat the material with an electron beam, CVD (chemical vapor deposition) methods, ALD (atomic layer deposition) methods, and other vapor phase film formation methods. It is particularly preferred to form the buffer layer 21 by physical vapor deposition without using substrate heating as much as possible. In particular, the EB vapor deposition method is preferred because it can easily form the amorphous buffer layer 21 without adjusting the substrate temperature during film formation.

[0059] CMP polishing can be used when polishing the surfaces of the amorphous buffer layer 21, the phosphor plate 20, and the light emitting element 10. CMP polishing uses nano slurry (diamond, silicon dioxide, or aluminum oxide) having a particle size of several nanometers to several tens of nanometers.

[0060] Specifically, for example, the phosphor plate 20 is ground by CMP (chemical mechanical polishing) using a slurry containing diamond particles with a particle size of 50 nm as abrasive particles, and the ground surface is further finely cut as needed. After ultraviolet light (such as excimer light) treatment and plasma treatment are performed to remove organic contaminants on the surface and activate the bonding surface (cut the bonds of surface molecules to form dangling bonds), the buffer layer 21 is formed by physical vapor deposition (EB, sputtering) or vapor phase growth method (ALD or CVD).

[0061] The surface of the buffer layer 21 has an uneven shape following the unevenness of the polished surface of the phosphor plate 20 immediately after film formation, but the buffer layer 21 can be flattened to a roughness below the distance where intermolecular forces act (≤ 0.5 nm) by CMP polishing.

[0062] In the CMP polishing of the buffer layer 21 , for example, the CMP polishing is performed using a platen on which a buff having a relatively low hardness is mounted and a silica-based slurry.

[0063] In addition, by using an amorphous buffer layer 21, the hardness is lower than that of a buffer layer 21 composed of a single crystal, and the buffer layer 21 has flexibility when the phosphor plate 20 provided with the buffer layer 21 is brought into contact with the element substrate 11. Therefore, by applying pressure, the buffer layer 21 is plastically deformed and can be closely attached to the surface shape of the element substrate 11, so that surface activation bonding can be easily performed.

[0064] In addition, the buffer layer 21 preferably does not contain voids. If voids are contained, the surface flatness of the buffer layer 21 deteriorates, which becomes a factor that reduces the bonding strength of the surface activated bonding.

[0065] In addition, in the present embodiment, when manufacturing the semiconductor light emitting device 1, a laminate is formed by bonding a large phosphor plate 20 of a plurality of semiconductor light emitting devices 1 to a large element substrate 11 having a structure in which a plurality of light emitting elements 10 are continuous. Then, in order to divide the laminate at the boundary position of the plurality of semiconductor light emitting devices 1 to form individual semiconductor light emitting devices 1, a notch is formed from the phosphor plate 20 side of the laminate by dicing or the like, and a notch is formed from the light emitting layer 12 side of the element substrate 11.

[0066] At this time, the cut is formed to penetrate the buffer layer 21. Specifically, the cut is formed to penetrate the buffer layer 21 and reach the element substrate 11. That is, the cut is formed to penetrate the bonding surface between the phosphor plate 20 and the light-emitting element plate 100 (in this embodiment, the interface between the buffer layer 21 and the element substrate 11) and reach the light-emitting element plate 100 (in this case, the element substrate 11).

[0067] This releases the internal stress of the joint surface between the phosphor plate 20 and the element substrate 11, and prevents the stress from concentrating on the joint surface when a force is applied from the outside, thereby preventing the element substrate 11 and the phosphor plate from peeling off at the joint surface. This improves the manufacturing yield.

[0068] When the buffer layer 21 is provided on both the phosphor plate 20 and the element substrate 11 , the interface between the first buffer layer on the phosphor plate 20 side and the second buffer layer on the element substrate 11 side becomes the bonding interface. Therefore, the cut is formed to penetrate at least the first buffer layer and the bonding surface.

[0069] When the buffer layer 21 is provided only on the element substrate 11 side, the interface between the buffer layer 21 and the phosphor plate 20 becomes the bonding surface, and thus the cutout is formed to penetrate at least the phosphor plate 20 and the bonding surface.

[0070] <Manufacturing method>

[0071] Figure 2 and Figure 3 It is a diagram for explaining the method for manufacturing the semiconductor light emitting device according to the present embodiment. Figure 4 Yes means Figure 3 (c) is a cross-sectional view of the shape of the stacked body after the manufacturing step.

[0072] use Figure 2 to Figure 4 Each manufacturing process is described.

[0073] (Polishing Step of Light Emitting Element 10)

[0074] First, if Figure 2 As shown in (a), a light-emitting element plate 100 is prepared in which a plurality of semiconductor light-emitting layers 12 and electrodes 13 are arranged with gaps in the main plane direction on the lower surface of a continuous element substrate 11. The spacing between the plurality of semiconductor light-emitting layers 12 of the light-emitting element plate 100 is designed so that individual light-emitting elements 10 can be obtained by dividing the element substrate 11 at the boundaries of adjacent light-emitting elements 10.

[0075] like Figure 2 As shown in (a) of FIG. 1 , the support substrate 50 is bonded to the plurality of semiconductor light emitting layers 12 arranged on the light emitting element panel 100 via the heat resistant adhesive layer 60 .

[0076] like Figure 2 As shown in (b) , the back side (the surface opposite to the side to which the semiconductor light emitting layer 12 is bonded) of the support substrate 50 is fixed to the polishing stage 80 - 1 via the adhesive layer 90 - 1 .

[0077] Prepare a grinding platform 70-1, use a slurry containing diamond abrasives, and use the grinding platform 70-1 to cut and grind the back side of the element substrate 11 of the light-emitting element plate 100 to make it thinner, and make the surface of the element substrate 11 flat to a roughness (Ra) below the distance where intermolecular forces act (less than ~0.5nm).

[0078] Specifically, for example, a grinding process, a mechanical polishing process, and a CMP polishing process are sequentially performed using the polishing platen 70 - 1 .

[0079] For example, in the grinding process, a grinding stone with a grain size of #230 is used to reduce the thickness (for example, 830 μm) of the element substrate 11 to 150 μm by a grinding device. The roughness (Ra) of the element substrate 11 after grinding is about 200 nm.

[0080] Next, in the mechanical polishing process, the surface of the element substrate 11 having a thickness of 150 μm after the grinding process is subjected to the first mechanical polishing using a slurry containing diamond abrasive grains with a particle size of 6 μm, thereby making the roughness (Ra) of the element substrate 11 less than 50 nm. Through this first mechanical polishing process, the surface damage and crack layer generated in the grinding process can be removed. The thickness of the element substrate after the first mechanical polishing process is about 120 μm. Then, a second mechanical polishing is performed using a slurry containing diamond abrasive grains with a particle size of 1 μm, thereby making the roughness (Ra) of the element substrate 11 less than 10 nm.

[0081] Next, in the CMP polishing step, CMP polishing is performed using a slurry containing diamond abrasive grains having a particle size of 50 nm, thereby reducing the roughness (Ra) of the element substrate 11 to less than 0.5 nm.

[0082] Through these steps, the surface of the element substrate 11 can be flattened to a roughness (Ra) (less than 0.5 nm) that is less than the distance (~0.5 nm or less) at which intermolecular forces act.

[0083] Then, if Figure 2 As shown in (c), the surface of the polished element substrate 11 is subjected to ultraviolet light (excimer light) treatment and plasma treatment.

[0084] Specifically, the polished surface of the element substrate 11 is irradiated with ultraviolet light (excimer light: wavelength (175±15) nm) and cleaned.

[0085] Next, the light-emitting element plate 100 is arranged in a vacuum device, and a plasma of any one of Ar, O2, N2 or a mixed gas of two or more is generated by high-frequency power (100W to 450W, preferably 250W to 350W). The polished surface of the element substrate 11 is subjected to plasma treatment for a specified treatment time (1 minute to 10 minutes, preferably 3 minutes to 6 minutes) to activate the surface.

[0086] Thereby, impurities on the surface of the element substrate 11 are removed, and dangling bonds are generated. Then, by exposing the element substrate 11 to the air, hydroxyl groups (—OH) are formed on the dangling bonds on the plasma irradiated surface.

[0087] (Polishing Step of Phosphor Plate 20)

[0088] On the other hand, Figure 2 As shown in (d), a phosphor plate 20 of a size that is continuous with the phosphor plates 20 of a plurality of semiconductor light emitting devices 1 is prepared and fixed to the polishing stage 80 - 2 by means of an adhesive layer 90 - 2 .

[0089] The grinding platen 70 - 2 is prepared, and the surface of the phosphor plate 20 is ground using the grinding platen 70 - 2 using slurry containing diamond abrasive grains.

[0090] Specifically, for example, a mechanical polishing process and a CMP polishing process are sequentially performed using the polishing platform 70 - 2 .

[0091] In the mechanical polishing step, the surface of the phosphor plate 20 is mechanically polished using a slurry containing diamond abrasive grains with a particle size of 6 μm, and then mechanically polished using a slurry containing diamond abrasive grains with a particle size of 1 μm, thereby reducing the roughness (Ra) of the element substrate 11 to less than 10 nm.

[0092] Next, in the CMP polishing step, CMP polishing is performed using a slurry containing diamond abrasive grains with a particle size of 50 nm to reduce the roughness (Ra) of the phosphor plate to less than 1 nm. The CMP polishing step is performed as necessary.

[0093] Thereafter, the polishing stage 80 - 2 is removed from the phosphor plate 20 .

[0094] (Film Formation and Polishing of Buffer Layer 21)

[0095] Then, if Figure 2 As shown in (e) , an amorphous buffer layer 21 is formed on the polished surface of the phosphor plate 20 .

[0096] Here, an amorphous aluminum oxide (Al2O3, etc.) film with a thickness of 600 nm is formed on the polished surface of the phosphor plate 20 by EB evaporation as the buffer layer 21. Specifically, for example, Al2O3 powder for evaporation is used as an evaporation source, and the evaporation layer is heated to 100°C under an oxygen partial pressure of 1×10 -2 Under Pa, an aluminum oxide (Al 2 O 3 or the like) film is formed without heating or cooling the substrate (phosphor plate 20 ).

[0097] Then, if Figure 2 As shown in (f) of FIG. 8 , the surface of the phosphor plate 20 opposite to the surface on which the buffer layer 21 is formed is fixed to the polishing stage 80 - 3 by an adhesive layer 90 - 3 .

[0098] A polishing platform 70-3 is prepared, and a slurry containing silica particles of several nm to several tens of nm is used to perform CMP polishing on the surface of the buffer layer 21 of the phosphor plate 20 using the polishing platform 70-3 to make the roughness (Ra) less than 0.5 nm. This roughness is the roughness (Ra) below the distance (~0.5 nm or less) where the intermolecular force acts.

[0099] Then, if Figure 2 As shown in (g), the surface of the polished phosphor plate 20 is subjected to ultraviolet light (quasi-molecular light) treatment and plasma treatment, and after forming dangling bonds, it is exposed to the atmosphere to form hydroxyl groups (-OH) at the dangling bonds DB. The conditions of these treatments are similar to those of Figure 2 is the same as (c), so the description is omitted.

[0100] Best Figure 2 (c) The ultraviolet light (excimer light) treatment and plasma treatment of the element substrate 11 and Figure 2 The ultraviolet light (excimer light) treatment and plasma treatment of the phosphor plate 20 in (g) are completed simultaneously.

[0101] After the plasma treatment, the light emitting element 10 and the phosphor plate 20 are taken out from the vacuum apparatus.

[0102] (Joining process)

[0103] Then, if Figure 3 As shown in (a), the light-emitting element plate 100 supported by the supporting substrate 50 is mounted on the heating and pressing stage 200, and the phosphor plate 20 is mounted thereon. At this time, the light-emitting element plate 100 is mounted in such a manner that the surface of the element substrate 11 that has been polished, treated with ultraviolet light (excimer light) and plasma is in contact with the surface of the buffer layer 21 that has been polished, treated with ultraviolet light (excimer light) and plasma is in contact with the surface of the buffer layer 21 of the phosphor plate 20. As a result, the surface of the element substrate 11 and the surface of the buffer layer 21 of the phosphor plate 20 form hydrogen bonds with each other through hydroxyl groups to form hydrogen bonding parts, thereby being temporarily bonded.

[0104] Then, in Figure 3 In the state of (a), the light emitting element plate 100 and the phosphor plate 20 are heated to 100°C to 300°C, preferably 150°C to 250°C under normal pressure by the heating and pressing stage 200. Furthermore, a load (for example, 2 MPa or more, preferably 10 MPa or more) is applied to the light emitting element plate 100 and the phosphor plate 20 by the heating and pressing stage 200. The heating and pressing state is maintained for more than 30 minutes, preferably for more than 2 hours, and the light emitting element plate 100 and the phosphor plate 20 are bonded by surface activated bonding.

[0105] By surface activated bonding, the element substrate 11 and the phosphor plate 20 are bonded to form a laminate through the buffer layer 21. At this time, the hydroxyl groups are thermally decomposed by pressure and heat, and the hydrogen atoms in the hydroxyl groups are driven out to form oxygen bonds. On the other hand, the remaining hydroxyl groups become water, hydrogen (H2O, H2), etc. and detach from the bonding interface.

[0106] Alternatively, the light emitting element plate 100 and the phosphor plate 20 may be placed in a vacuum device and bonded together by heating and pressurizing them under reduced pressure.

[0107] (Incision Forming Process)

[0108] like Figure 3 As shown in (b) , a groove-shaped cutout 110 of a predetermined depth is formed from the phosphor plate 20 side of the stacked body at a position corresponding to the gap between the plurality of semiconductor light emitting layers.

[0109] The cutout 110 reaches the buffer layer 21 and penetrates the buffer layer 21. The cutout 110 penetrates the bonding surface between the phosphor plate 20 and the light emitting element plate 100 and reaches the element substrate 11.

[0110] Specifically, the cutout 110 is formed by blade dicing using a blade having a blade width of 20 μm to 500 μm. The cutout 110 is formed to extend beyond the phosphor plate 20 and the buffer layer 21 and penetrate into the element substrate 11 to a depth of 1 μm to 50 μm, preferably 1 μm to 20 μm.

[0111] In addition, if Figure 5 As shown in (a) to (e), the cross-sectional shape of the cutout 110 may be a rectangle ( Figure 5 (a)), trapezoidal ( Figure 5 (b)), a rounded rectangle ( Figure 5 (c)), rounded trapezoid ( Figure 5 (d)), parabolic ( Figure 5 Any of (e)), but preferably a rounded shape ( Figure 5 (c) to (e)), particularly preferably a parabolic shape ( Figure 5 (e)).

[0112] The cross section is parabolic ( Figure 5 The cutout 110 of (e)) is a shape that is closest to the lower surface (surface on which the semiconductor light emitting layer 12 is mounted) of the element substrate 11 at one point at the front end 110a of the cross section of the cutout. Therefore, in the singulation process described later, by applying force to the stacked body, stress is concentrated at a point at the front end of the front end 110a, and the element substrate 11 can be divided by cleavage or the like starting from this position.

[0113] In addition, although the cutout 110 is formed by blade cutting here, the cutout 110 may also be formed by laser cutting.

[0114] (Notch Forming Process)

[0115] Next, if Figure 3 As shown in (c), the support substrate 50 is removed from the semiconductor light emitting layer 12, and the adhesive sheet 120 is attached to the phosphor plate 20 side of the laminate.

[0116] A groove-shaped notch 130 is formed in the element substrate 11 in the gap between the plurality of semiconductor light emitting layers 12 from the light emitting element panel 100 side of the stacked body.

[0117] Specifically, for example, a laser scribing device is used to focus laser light 170 using lens 171 and irradiate the laser light onto element substrate 11 in the gaps between the plurality of semiconductor light emitting layers 12 , thereby forming groove-shaped notches 130 .

[0118] The sum of the depth of the notch 130 and the depth of the cut 110 is shallower than the thickness of the laminate. The laminate is divided by rupture such as cleavage.

[0119] In addition, a laser scribing device may be used to form a protective film on the surface of the semiconductor light emitting layer by coating before forming the notch 130. The protective film prevents dirt generated by laser scribing from adhering to the surface of the semiconductor light emitting layer. The protective film can be removed by water washing in a subsequent process.

[0120] Nano-pulse or pico-pulse laser is preferably used as the laser 170. As the wavelength of the laser 170, a wavelength of 355 nm can be used.

[0121] The shape of the notch 130 is preferably a wedge shape, and the width of the notch 130 is preferably 10 μm or less, and particularly preferably 2 μm or less. The depth of the notch 130 is preferably 2 μm or more, and particularly preferably 5 μm or more.

[0122] Thus, the laminate becomes Figure 4 shape.

[0123] After the notches 130 are formed, the laminate is washed with water and organic cleaning to remove contaminants caused by laser scribing.

[0124] In addition, Figure 3 In (c), the laser 170 is irradiated from the semiconductor light emitting layer 12 side, but the laser 170 may be irradiated from the phosphor plate 20 side. Figure 3 The notch 130 is formed at the position of the notch 130 of the element substrate 11 in (c). For example, the cut surface can be formed on the element substrate 11 using a stealth dicing device.

[0125] Here, since the intervals between the semiconductor light emitting layers 12 are narrow, the notches 130 are formed by laser scribing. However, the notches 130 may be provided by blade dicing using a thin blade.

[0126] (Singularization process)

[0127] like Figure 3 As shown in (d) , the laminate is attached to the adhesive sheet 150 with the light emitting element 10 facing downward.

[0128] When the entire surface of the phosphor plate 20 of the laminate is pressed by the roller 140, the front end 110a of the cutout 110 and the front end 130a of the notch 130 (see Figure 5 The element substrate 11 between (e) is cut and broken (refer to Figure 5 (e)). Thus, the semiconductor light emitting device 1 is individualized.

[0129] It should be noted that the temperature rise caused by the laser irradiation causes the element substrate 11 to warp. Figure 3 In the step (c), by appropriately setting the conditions when forming the notch 130 by irradiating the laser 170, the element substrate 11 between the notch 130 and the cut 110 can be cleaved and singulated by only forming the notch 130 by irradiating the laser 170. In this case, the step of applying force by the roller 140 can be omitted.

[0130] (Step of spacing semiconductor light emitting devices 1)

[0131] Finally, if Figure 3 As shown in (e), the adhesive sheet 150 is stretched (expanded) in the main plane direction to increase the intervals between the semiconductor light emitting devices 1 on the adhesive sheet 150. As a result, the semiconductor light emitting devices 1 are ready for operation.

[0132] Through the above steps, the semiconductor light emitting device 1 can be manufactured (see Figure 1 ).

[0133] As described above, in this embodiment, by providing the buffer layer 21 and polishing the buffer layer 21 , the phosphor plate 20 can be bonded to the light-emitting device by the surface activated bonding method without being affected by the crystal grains of the phosphor plate 20 .

[0134] In addition, in this embodiment, for the laminate formed by surface-activated bonding of the element substrate 11 of the light-emitting element plate 100 and the phosphor plate, the cut 110 is set to a depth reaching the buffer layer 21, thereby preventing peeling at the bonding surface due to internal stress or external force on the bonding surface. Furthermore, in the cutting when the cut 110 is set, the substrate cutting (about 5μm to 20μm) after penetrating the bonding surface is almost not performed, so a narrow cutting blade can be used. Therefore, the width of the cut 110 set between the light-emitting elements can be formed to be smaller.

[0135] In addition, by providing the notch 130 between adjacent semiconductor light-emitting layers, the element substrate therebetween can be easily and precisely divided by cleavage or the like at the position connecting the notch 130 and the cutout 110. Therefore, the phosphor plate and the element substrate can be accurately divided and singulated into individual semiconductor light-emitting devices 1, thereby improving the manufacturing yield.

[0136] In addition, in this embodiment, if Figure 1 As shown in FIG. 1 , a semiconductor light emitting device having a pair of electrodes 13 is manufactured. Figure 6 As shown in (a) and (b) of FIG. 1 , a structure including two pairs of electrodes 13 in one semiconductor light emitting device can also be manufactured by the above-mentioned manufacturing process.

[0137] <Evaluation>

[0138] The cross section of the buffer layer 21 of the manufactured semiconductor light emitting device was confirmed by TEM (transmission electron microscope), and no lattice and grains were observed, confirming that the buffer layer 21 was amorphous. Therefore, it is inferred that when the buffer layer 21 is measured by X-ray diffraction, no diffraction peak appears in the X-ray diffraction pattern.

[0139] <Effect>

[0140] The semiconductor light emitting device of the first embodiment can be operated in the atmosphere by disposing the amorphous buffer layer 21 between the phosphor plate 20 and the light emitting element 10. Figure 3 (a) is a step of bonding the phosphor plate 20 and the light emitting element 10 by surface activation bonding.

[0141] Furthermore, by using the amorphous buffer layer 21, even when the phosphor plate 20 uses a material such as a composite ceramic phosphor plate that is difficult to make the surface unevenness flat to a roughness (less than 0.5 nm) that enables surface activated bonding, the amorphous buffer layer 21 can be relatively easily made to have a roughness of less than 0.5 nm, thereby enabling bonding based on surface activated bonding. Therefore, a semiconductor light-emitting device with a highly reliable bonding surface based on surface activated bonding can be provided.

[0142] When Al2O3 is used as the material of the amorphous buffer layer 21, the refractive index and thermal expansion coefficient are close to those of the element substrate 11 and the phosphor plate. When made into a thin film, the thermal conductivity is also large and the Young's modulus is high, so it is not easily damaged. Therefore, it is possible to provide a semiconductor light-emitting device with high light extraction efficiency, good heat dissipation, and not easy to be damaged.

[0143] In particular, when aluminum oxide (Al2O3, etc.) is used as the material of the amorphous buffer layer 21, a sapphire substrate is used as the element substrate 11, and a composite ceramic phosphor plate (Al2O3 / Ce:YAG) is used as the phosphor plate 20, the same type of bonding can be used to stably perform bonding through surface activated bonding.

[0144] <<Second embodiment>>

[0145] A semiconductor light emitting device according to a second embodiment will be described. Figure 7 As shown, the semiconductor light emitting device of the second embodiment does not include the element substrate 11 , and the semiconductor light emitting layer 12 and the phosphor plate 20 are bonded to each other via the buffer layer 21 .

[0146] use Figure 8 and Fig. 9 A method for manufacturing a semiconductor light emitting device according to the second embodiment is described. Figure 8 and Fig. 9 In the manufacturing process, Figure 2 and Figure 3 The same manufacturing process will be briefly described.

[0147] like Figure 8 As shown in (a), a light emitting element panel 100 in which a semiconductor light emitting layer 12 is formed on the front surface of an element substrate 11 is prepared.

[0148] like Figure 8 As shown in (b) of FIG. 1 , the semiconductor light emitting layer 12 is processed into the shape of the semiconductor light emitting layer 12 of each semiconductor light emitting device by etching or the like. Then, a pair of electrodes 13 are formed on each of the semiconductor light emitting layers 12 .

[0149] like Figure 8As shown in (c) , the electrode 13 of the semiconductor light emitting layer 12 is fixed to a light-transmitting support substrate 301 by an adhesive layer 302 made of a resin adhesive. The support substrate 301 is mounted on a support stand 310 .

[0150] like Figure 8 As shown in (d) of FIG. 1 , the element substrate (sapphire substrate) 11 is irradiated with laser light such as excimer laser light, and the element substrate 11 is removed by laser stripping. Figure 8 As shown in (e), the semiconductor light emitting layer 12 is exposed.

[0151] exist Figure 8 In (e), the exposed semiconductor light emitting layer 12 is polished, the surface is flattened, and ultraviolet light (excimer light) treatment and plasma treatment are performed. Figure 2 The steps (a) to (c) are similarly performed by polishing, ultraviolet light (excimer light) treatment, and plasma treatment.

[0152] exist Figure 8 In the step (f), the phosphor plate 20 is ground to form an amorphous buffer layer 21 on the ground surface. The surface of the buffer layer 21 is ground and subjected to ultraviolet light (excimer light) treatment and plasma treatment. Figure 2 These treatments are carried out in the same manner as in steps (d) to (g).

[0153] exist Figure 8 In step (g), the phosphor plate 20 is placed on the semiconductor light emitting layer 12 in contact with the buffer layer 21, and heating and pressurization are performed to surface activate and bond the semiconductor light emitting layer 12 and the phosphor plate 20. Figure 3 This step is carried out in the same manner as step (a).

[0154] Then, in Fig. 9 In the step (a), ultraviolet light is irradiated to generate bubbles, thereby removing the support substrate 301 and the adhesive layer 302 from the semiconductor light emitting layer 12 .

[0155] In addition, when a substrate such as Si is used as the supporting substrate 301 and the semiconductor light-emitting layer 12 is installed via an adhesive layer 302 composed of a metal material, a sacrificial layer composed of silver is formed as an intermediate layer of the adhesive layer 302, and the sacrificial layer is dissolved using nitric acid or the like, thereby removing the supporting substrate 301 and the adhesive layer 302.

[0156] exist Fig. 9 In the step (b) of the first embodiment, the adhesive sheet 350 is attached to the semiconductor light emitting layer 12 side for support, and the cutout 341 is formed on the phosphor plate 20. Figure 3The step (b) is performed in the same manner as in the first embodiment, but the depth of the cutout 341 is formed so as not to reach the buffer layer 21 , which is different from the first embodiment.

[0157] exist Fig. 9 In the step (c), the adhesive sheet 350 is removed, and the adhesive sheet 360 is adhered to the phosphor plate 20 side and supported. From the light emitting element plate 100 side of the stacked body, the laser 170 is focused by the lens 171 on the buffer layer 21 in the gap between the plurality of semiconductor light emitting layers 12 to form a groove-shaped notch 342. Figure 3 The step (c) is performed in the same manner as in the first embodiment, but is different from the first embodiment in that the notches 342 are directly formed in the buffer layer 21 .

[0158] In addition, in this embodiment, the notch 342 is formed, but since the buffer layer 21 is a thin film, it can be arbitrarily formed as needed. That is, the notch 342 may not be provided.

[0159] In addition, a notch 342 or the like may be formed at the front end of the cutout 341 .

[0160] Then, the adhesive sheet 360 is removed, and the adhesive sheet 370 is again attached and supported on the semiconductor light emitting layer 12 side, which is similar to the first embodiment. Figure 3 The steps (d) and (e) are carried out in the same manner. Fig. 9 (d)~ Fig. 9 In step (e), each semiconductor light-emitting device is singulated.

[0161] As described above, in the second embodiment, even in the light emitting element 10 from which the element substrate 11 is removed, the phosphor plate 20 can be bonded by surface activated bonding.

[0162] In the present embodiment, since the notch 342 is provided in the buffer layer 21 , it is possible to prevent stress from being applied to the light emitting element 10 .

[0163] Other effects are the same as those of the first embodiment.

[0164] <<Third Embodiment>>

[0165] use Fig.10 A semiconductor light emitting device according to a third embodiment is described. Figure 7 The semiconductor light emitting device of the second embodiment shown in FIG. 1 has the same structure as that of the semiconductor light emitting device of the second embodiment shown in FIG. 1 , but the manufacturing process is different from that of the second embodiment. Fig. 9In the steps (b) to (d), the notches 341 and the cutouts 342 are formed to separate the phosphor plate 20 and separate the semiconductor light emitting devices. However, in the third embodiment, the phosphor plate 20 is cut by dicing.

[0166] use Fig.10 A method for manufacturing a semiconductor light emitting device according to the third embodiment is described. Fig.10 In the manufacturing process, Figure 8 and Fig. 9 The same manufacturing process is briefly described.

[0167] and Figure 8 (a)~ Figure 8 (g) and Fig. 9 The process (a) is carried out in the same manner. Fig.10 (a)~ Fig.10 Thus, a stacked body is formed in which the common phosphor plate 20 is bonded to the upper surface of the semiconductor light emitting layers 12 arranged at intervals via the buffer layer 21 .

[0168] Then, in Fig.10 In step (i), the laminate is supported by bonding sheet 330 on the semiconductor light emitting layer 12 side. The phosphor plate 20 and the buffer layer 21 are separated by cutting 340 from the phosphor plate 20 side. Thus, the semiconductor light emitting device is separated into individual pieces.

[0169] Finally, if Fig.10 As shown in (j), the adhesive sheet 330 is stretched (expanded) in the main plane direction to increase the intervals between the semiconductor light emitting devices on the adhesive sheet 330. As a result, the semiconductor light emitting devices are ready for operation.

[0170] Thus, it is possible to produce Figure 7 Semiconductor light emitting device.

[0171] In the manufacturing method of the third embodiment 3, in order to cut the phosphor plate 20 by dicing, it is preferable to arrange the semiconductor light emitting layer 12 with the interval expanded by the width of the cut 340 generated by the thickness of the dicing blade, compared with the method of cutting as in the second embodiment.

[0172] <<Fourth embodiment>>

[0173] use Fig.11 , Fig.12 , Fig.13 A semiconductor light emitting device according to a fourth embodiment will be described. Fig.11 As shown, the semiconductor light emitting device of the fourth embodiment is Figure 7The semiconductor light emitting device of the second embodiment shown similarly has a structure without the element substrate 11 , but is different from the second embodiment in that a Si substrate 201 is provided instead of a wiring substrate 30 for supplying power to the semiconductor light emitting element 10 .

[0174] The Si substrate 201 has a pair of upper surface electrodes 211 and 212 on the upper surface and a pair of lower surface electrodes 221 and 222 on the lower surface. One upper surface electrode 211 and one lower surface electrode 221 are connected by a through electrode 231 penetrating a through hole provided in the Si substrate 201 .

[0175] The pair of upper surface electrodes 211 and 212 are respectively connected to the pair of electrodes 13 of the semiconductor light emitting element 10 .

[0176] Insulating layer 232 is disposed between through electrode 231 and the inner wall of the through hole, between the lower surface of upper electrode 211 and Si substrate 201, and between the upper surface of lower electrode 221 and Si substrate 201. Thus, current flows to upper electrode 211 via lower electrode 221 and through electrode 231.

[0177] The current flows from the other lower surface electrode 222 to the other upper surface electrode 212 via the Si substrate 201 .

[0178] use Fig.12 A method for manufacturing a semiconductor light emitting device according to a fourth embodiment is described. Fig.12 In the manufacturing process, Figure 8 and Fig. 9 The same manufacturing process is briefly described.

[0179] Fig.12 (a) Fig.12 The process of (b) and Figure 8 (a) Figure 8 The same process as in step (b) is performed. Thus, a plurality of semiconductor light emitting layers 12 are formed at predetermined intervals on the element substrate 11 , and a pair of electrodes 13 are formed on the semiconductor light emitting layers 12 .

[0180] exist Fig.12 In the step (c), the pre-prepared Fig.11 The upper surface electrodes 211 and 212 of the Si substrate 201 having a structure of are fixed to the electrode 13 of the semiconductor light emitting layer 12. The Si substrate 201 is mounted on a support 210.

[0181] exist Fig.12 In the step (d), Figure 8 (d) Similarly, the element substrate 11 is removed by laser lift-off.

[0182] exist Fig.12 In the step (e), Figure 8 (e) Similarly, the semiconductor light emitting layer 12 is polished to planarize the surface, and subjected to ultraviolet light (excimer light) treatment and plasma treatment.

[0183] exist Fig.12 In the process (f), Figure 8 (f) Similarly, the phosphor plate 20 is polished to form an amorphous buffer layer 21 on the polished surface. The surface of the buffer layer 21 is polished, and ultraviolet light (excimer light) treatment and plasma treatment are performed.

[0184] exist Fig.12 In the process (g), Figure 8 (g) Similarly, the phosphor plate 20 is placed on the semiconductor light emitting layer 12 in contact with the buffer layer 21, and the semiconductor light emitting layer 12 and the phosphor plate 20 are surface activated and bonded to each other by heating and pressing. An adhesive sheet 220 is attached to the lower surface of the Si substrate 201.

[0185] Then, in Fig.12 In step (h), the phosphor plate 20 is cut at a position between the semiconductor light emitting devices 1 by dicing or laser cutting, and the Si substrate 201 is also cut by direct dicing. Thus, the semiconductor light emitting devices are separated into individual pieces.

[0186] Finally, if Fig.12 As shown in (i), the adhesive sheet 150 is stretched (expanded) in the main plane direction to increase the intervals between the semiconductor light emitting devices 1 on the adhesive sheet 220. As a result, the semiconductor light emitting devices are ready for operation.

[0187] Thus, it is possible to produce Fig.11 Semiconductor light emitting device.

[0188] In addition, Fig.12 In the manufacturing method of Fig.12 In the step (h), the phosphor plate 20 and the Si substrate 201 are cut and separated at once by dicing or laser cutting, but the phosphor plate 20 and the Si substrate 201 may be cut separately. Fig.12 The process (h) is carried out Fig.13 The steps (h-1) and (h-2) are as follows.

[0189] exist Fig.13 In the step (h-1), the cutout 241 for cutting only the phosphor plate 20 is formed by dicing. The adhesive sheet 240 is attached to the upper surface of the phosphor plate 20 to support the phosphor plate 20 .

[0190] Next, in Fig.13 In the step (h-2), the phosphor plate 20 is arranged at the bottom, and the adhesive sheet 220 of the Si substrate 201 is peeled off. In this state, a cut 242 is formed by laser cutting to cut the Si substrate 201. Thus, the semiconductor light-emitting device is singulated. The adhesive sheet 220 is attached to the upper surface of the Si substrate 201 to support the Si substrate 201.

[0191] Finally, if Fig.13 As shown in (i), the adhesive sheet 240 is peeled off, and the adhesive sheet 220 is stretched (expanded) in the main plane direction to increase the interval between the semiconductor light emitting devices 1 on the adhesive sheet 220. As a result, the semiconductor light emitting devices are ready for operation.

[0192] exist Fig.13 (h-1) and Fig.13 In the step (h-2), the phosphor plate 20 and the Si substrate 201 are cut separately, and therefore appropriate dicing blades, laser irradiation conditions for laser cutting, etc. can be set separately.

[0193] In addition, Fig.13 In the process (h-1) of Fig.13 In the process (h-2), an example of using laser cutting is described, but cutting and laser cutting can also be reversed, and both can be cut by cutting or laser cutting under different conditions.

[0194] Fourth embodiment Fig.11 The semiconductor light-emitting device is the main component form of blue LED that has established a mass production process similar to flip chips. It also includes a component form without a substrate through-hole structure, and can be mounted on a phosphor plate at the wafer level. In addition, compared with the phosphor mounting structure using an adhesive with poor thermal conductivity and low refractive index, Fig.11 The semiconductor light-emitting device can improve light and extraction efficiency and optimize the heat dissipation of the phosphor.

[0195] The technology of the semiconductor light emitting device of the present embodiment described above can be used for a lamp light source unit or a white light source module.

[0196] Description of Reference Numerals

[0197] 1 Semiconductor light-emitting device

[0198] 10 Light-emitting element

[0199] 11 Component substrate

[0200] 12 Semiconductor light emitting layer

[0201] 13 Electrodes

[0202] 18 Buffer layer

[0203] 20 Phosphor Plate

[0204] 21 Buffer layer

[0205] 30 Wiring substrate

[0206] 31 substrate

[0207] 32 Wiring

[0208] 40 Light reflective multilayer film

[0209] 50 Support base plate

[0210] 60 Heat-resistant adhesive layer

[0211] 70 Grinding Platform

[0212] 80 Grinding stage

[0213] 90 Adhesive layer

[0214] 100 Light emitting element board

[0215] 110 Incision

[0216] 110a front end

[0217] 120 Adhesive Sheet

[0218] 130 Gap

[0219] 130a Front End

[0220] 140 Roller

[0221] 150 Adhesive Sheet

[0222] 170 Laser

[0223] 171 Lens

[0224] 200 Pressurized Table

[0225] 201 Si substrate

[0226] 210 Adhesive Sheet

[0227] 211 Upper surface electrode

[0228] 212 Upper surface electrode

[0229] 220 Adhesive Sheet

[0230] 221 Lower surface electrode

[0231] 222 Lower surface electrode

[0232] 231 Through electrode

[0233] 232 Insulation layer

[0234] 240 Adhesive Sheet

[0235] 241 Incision

[0236] 242 Incision

[0237] 301 Support base plate

[0238] 302 Adhesive layer

[0239] 310 Supporting platform

[0240] 330 Adhesive Sheet

[0241] 340 Incision

[0242] 341 Incision

[0243] 342 Gap

[0244] 350 Adhesive Sheet

[0245] 360 Adhesive Sheet

[0246] 370 Adhesive Sheet

Claims

1. A semiconductor light emitting device, characterized in that: A light-emitting element including a semiconductor light-emitting layer and a phosphor plate bonded to the light-emitting element. A buffer layer composed of a dielectric material is arranged between the light emitting element and the phosphor plate so as to transmit light emitted by the light emitting element. The light emitting element is bonded to the phosphor plate via the buffer layer. The buffer layer is an amorphous layer.

2. The semiconductor light emitting device according to claim 1, characterized in that: When X-ray diffraction is measured, the buffer layer does not show a diffraction peak in the X-ray diffraction pattern.

3. The semiconductor light emitting device according to claim 1, characterized in that: The buffer layer is any one of an aluminum oxide layer, a niobium oxide layer, a zirconium oxide layer, a magnesium oxide layer, a silicon oxide layer, a titanium oxide layer, a tantalum oxide layer and a yttrium oxide layer.

4. The semiconductor light emitting device according to claim 1, characterized in that: The phosphor plate is bonded to the semiconductor light emitting layer via the buffer layer.

5. The semiconductor light emitting device according to claim 1, characterized in that: The semiconductor light emitting layer is bonded to the phosphor plate via the buffer layer. The semiconductor light emitting layer comprises a GaN layer, The buffer layer is an aluminum oxide layer.

6. The semiconductor light emitting device according to claim 1, characterized in that: The light emitting element includes an element substrate supporting the semiconductor light emitting layer. The element substrate is bonded to the phosphor plate via the buffer layer. The element substrate is sapphire, and the buffer layer is an aluminum oxide layer.

7. The semiconductor light emitting device according to claim 5 or 6, characterized in that: The phosphor plate is a composite ceramic phosphor plate in which phosphor particles are dispersed in an alumina ceramic matrix.

8. A method for manufacturing a semiconductor light-emitting device, wherein a phosphor plate is bonded to a light-emitting element including a semiconductor light-emitting layer, and the phosphor plate absorbs light emitted from the semiconductor light-emitting layer and emits fluorescence, characterized in that: The manufacturing method comprises: A light emitting element grinding step of grinding the upper surface of the light emitting element: a phosphor grinding step of grinding the lower surface of the phosphor plate; a film forming step of forming an amorphous buffer layer made of a dielectric material on at least one of an upper surface of the light emitting element and a lower surface of the phosphor plate; and The phosphor plate is mounted on the light emitting element so that the upper surface of the light emitting element faces the lower surface of the phosphor plate, and a bonding step is performed to bond the phosphor plate to the light emitting element by heating and pressurizing.

9. The method for manufacturing a semiconductor light emitting device according to claim 8, characterized in that: In the film forming step, the amorphous buffer layer is formed by a vapor deposition method in which a vapor deposition source is heated by an electron beam.

10. The method for manufacturing a semiconductor light emitting device according to claim 8, characterized in that: In the light emitting element grinding step, a plurality of light emitting elements are arranged on the support body with gaps therebetween along the main plane direction, and the upper surfaces of the plurality of arranged light emitting elements are ground. In the bonding step, the common phosphor plate is mounted on the arranged plurality of light emitting elements, and the upper surface of the light emitting element and the lower surface of the phosphor plate are bonded to each other via the buffer layer.

11. The method for manufacturing a semiconductor light emitting device according to claim 8, characterized in that: In the light emitting element grinding process, the light emitting element has a plurality of semiconductor light emitting layers arranged on the lower surface of a common element substrate, and the upper surface of the common element substrate is ground. In the bonding step, the upper surface of the element substrate and the lower surface of the phosphor plate are bonded via the buffer layer.

12. The method for manufacturing a semiconductor light emitting device according to claim 10, characterized in that: After the bonding step, a singulation step is further included, in which the phosphor plate is cut or severed at positions between the arranged plurality of light emitting elements.

13. The method for manufacturing a semiconductor light emitting device according to claim 11, characterized in that: After the bonding step, a singulation step is further included, in which the phosphor plate and the element substrate are cut or severed at positions between the arranged plurality of light emitting elements.

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