Light-emitting device

Abstract

The objective is to provide a light-emitting device that reduces the possibility of thermal stress generated during soldering adversely affecting the light-emitting element. [Solution] A light-emitting element comprising a pair of conductive members, solder arranged on the upper surfaces of the pair of conductive members, a semiconductor laminate, and a pair of electrodes arranged on the lower surface of the semiconductor laminate, wherein the upper surfaces of the pair of conductive members and the lower surfaces of the pair of electrodes are joined via the solder, a light-transmitting member arranged on the light-emitting element, and a support member arranged to the side of the light-emitting element. A light-emitting device comprising, wherein the pair of electrodes each comprises a base portion and an extended portion extending laterally from the side surface of the base portion, the extended portion having a curved lower surface, and the solder is in contact with the lower surface of the extended portion.

Description

Technical Field

[0001] The present disclosure relates to a light-emitting device.

Background Art

[0002] A light-emitting device in which a light-emitting element is joined to a conductive member via solder is known. (For example, Patent Document 1).

Prior Art Document

Patent Document

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] An embodiment according to the present disclosure aims to provide a light-emitting device that reduces the possibility that thermal stress generated during solder joining adversely affects the light-emitting element.

Means for Solving the Problems

[0005] The light-emitting device according to the embodiment includes a pair of conductive members, solders respectively disposed on upper surfaces of the pair of conductive members, a light-emitting element including a semiconductor laminate and a pair of electrodes disposed on a lower surface of the semiconductor laminate, wherein upper surfaces of the pair of conductive members and lower surfaces of the pair of electrodes are joined via the solders, a light-transmissive member disposed on the light-emitting element, a support member disposed on a side of the light-emitting element, and each of the pair of electrodes includes a base portion and an extending portion that extends laterally from a side surface of the base portion and has a curved lower surface, and the solder contacts the lower surface of the extending portion.

Effects of the Invention

[0006] According to embodiments of this disclosure, it is possible to provide a light-emitting device that reduces the possibility of thermal stress generated during soldering adversely affecting the light-emitting element. [Brief explanation of the drawing]

[0007] [Figure 1A] This is a schematic top view of the light-emitting device according to the embodiment of the disclosure. [Figure 1B] Figure 1A shows a schematic cross-sectional view and a partially enlarged view of the IB-IB line. [Figure 1C] These are schematic cross-sectional views and partially enlarged views of modified examples of the light-emitting device according to the embodiment of this disclosure. [Figure 2A] This is a schematic top view of a modified example of the light-emitting device according to the embodiment of the present disclosure. [Figure 2B] Figure 2A shows a schematic cross-sectional view and a partially enlarged view of the IIB-IIB line. [Figure 2C] Figure 2A shows a schematic cross-sectional view and a partially enlarged view of the IIC-IIC line. [Figure 3] This is a schematic cross-sectional view of a modified example of the light-emitting device according to the embodiment of this disclosure. [Figure 4A] This is a schematic cross-sectional view showing a method for manufacturing a light-emitting element according to an embodiment of the present disclosure. [Figure 4B] This is a schematic cross-sectional view showing a method for manufacturing a light-emitting element according to an embodiment of the present disclosure. [Figure 4C] This is a schematic cross-sectional view showing a method for manufacturing a light-emitting element according to an embodiment of the present disclosure. [Figure 4D] This is a schematic cross-sectional view showing a method for manufacturing a light-emitting element according to an embodiment of the present disclosure. [Figure 5A] This is a schematic cross-sectional view showing a method for manufacturing a light-emitting device according to an embodiment of the present disclosure. [Figure 5B] This is a schematic cross-sectional view showing a method for manufacturing a light-emitting device according to an embodiment of the present disclosure. [Figure 5C] This is a schematic cross-sectional view showing a method for manufacturing a light-emitting device according to an embodiment of the present disclosure. [Figure 5D]It is a schematic cross-sectional view showing a method of manufacturing a light-emitting device according to an embodiment of the present disclosure. [Figure 5E] It is a schematic cross-sectional view showing a method of manufacturing a light-emitting device according to an embodiment of the present disclosure. [Figure 5F] It is a schematic cross-sectional view showing a method of manufacturing a light-emitting device according to an embodiment of the present disclosure.

Embodiments for Carrying Out the Invention

[0008] Hereinafter, embodiments of the present invention will be described in detail based on the drawings. In the following description, terms indicating a specific direction or position (for example, "upper", "lower", "right", "left", and other terms including those terms) are used as necessary. The use of those terms is for facilitating the understanding of the invention with reference to the drawings, and the technical scope of the present invention is not limited by the meanings of those terms. Further, the plan view means viewing directly or through perspective from the upper surface or the lower surface. Also, portions denoted by the same reference numerals in a plurality of drawings indicate the same portions or members.

[0009] As shown in FIGS. 1A and 1B, the light-emitting device 100 according to the embodiment includes a conductive member 20, at least one light-emitting element 10 disposed on the conductive member 20 via solder 30, a light-transmissive member 40 disposed on the light-emitting element 10, and a support member 50 located on the side of the light-emitting element 10. Specifically, the conductive member 20 includes a first conductive member 21 and a second conductive member​​​The light-emitting element 10 includes a semiconductor laminate 11 and a pair of electrodes 12. The solder 30 is disposed between the lower surface 12L of the electrode 12 of the light-emitting element 10 and the upper surface 20U of the conductive member 20. The electrode 12 of the light-emitting element 10 includes a base portion 12B and an extension portion 12E that extends laterally from the side surface of the base portion 12B. The lower surface 12L of the electrode 12 is composed of a flat surface of the lower surface 12BL of the base portion 12B and a curved surface of the lower surface 12EL of the extension portion 12E. The solder 30 is disposed between the lower surface 12BL of the base portion 12B and the lower surface 12EL of the extension portion 12E and the upper surface 20U of the conductive member 20.

[0011] When the electrode 12 does not include the extension portion 12E, that is, when only the base portion 12B is present, when heating the solder 30, thermal stress is likely to be applied to the semiconductor laminate **********11 located directly above the end portion of the lower surface 12BL of the base portion 12B. Depending on the structure of the semiconductor laminate 11, this thermal stress may cause adverse effects such as cracks. In contrast, when the electrode 12 includes the extension portion 12E, a member different from the semiconductor laminate 11, for example, the support member 50 in the example shown in FIG. 1B, is located above the extension portion 12E. Therefore, the thermal stress applied when heating the solder 30 disposed on the lower surface 12EL of the extension portion 12E is less likely to be transmitted to the semiconductor laminate 11. In particular, when the lower surface 12EL of the extension portion 12E is a curved surface, the contact area with the solder 30 is larger than when it is a flat surface. Therefore, it is easier to disperse the thermal stress and the adverse effects on the semiconductor laminate 11 can be reduced more efficiently.

[0012] Further, since the lower surface 12EL of the extension portion 12E of the electrode 12 is a curved surface, the contact area with the solder 30 is increased. As a result, the heat from the semiconductor laminate 11 can be efficiently released, and a light-emitting device 100 with excellent heat dissipation can be obtained.

[0013] As shown in Figure 1B, the solder 30 can be in contact only with the lower surface 12L of the electrode 12. Alternatively, as shown in Figure 1C, the solder 30 may be in contact with both the lower surface 12L of the electrode 12 and the upper surface 12EU of the stretched portion 12E. By having the solder 30 in contact with the upper surface 12EU of the stretched portion 12E, the contact area between the electrode 12 and the solder 30 is increased, making it easier to disperse thermal stress and more efficiently reduce the load on the semiconductor laminate 11. In the example shown in Figure 1C, the solder 30 is in contact with the upper surface 12EU of only one of the pair of electrodes 12's stretched portion 12E, but it is not limited to this, and may be in contact with the upper surface 12EU of the stretched portion 12E of both electrodes 12.

[0014] The following provides a detailed explanation of each component.

[0015] (Conductive material) The conductive members 20, including a pair of conductive members 21 and a second conductive member 22, primarily function as power supply terminals that supply current from an external power source to the light-emitting element 10. The conductive members 20 may also comprise three or more conductive members 20. Furthermore, the conductive members 20 may include conductive members that do not contribute to current conduction. These non-conductive conductive members 20 can, for example, function as heat dissipation members.

[0016] Preferably, the distance between the electrodes 12 of the light-emitting element 10 is smaller than the distance between the pair of conductive members 20, that is, the distance between the first conductive member 21 and the second conductive member 22 (shortest distance). As a result, as shown in Figure 1B, there is a portion where the conductive member 20 is not located directly beneath the solder 30 placed on the lower surface 12L of the electrode 12. In the example shown in Figure 1B, the conductive member 20 is not located directly beneath most of the extended portion 12E of the electrode 12. Even in such a case, the heat generated from the light-emitting element 10 can be sufficiently transferred to the conductive member 20, thereby improving heat dissipation. However, this is not limited to this, and the distance between the electrodes 12 of the light-emitting element 10 may be greater than or the same as the distance between the first conductive member 21 and the second conductive member 22 (shortest distance). The shortest distance between the upper surfaces 20U of the first conductive member 21 and the second conductive member 22 is the distance between the end of the upper surface 20U of the first conductive member 21 and the end of the upper surface 20U of the second conductive member 22, and can be, for example, 50 μm or more and 200 μm or less.

[0017] The conductive member 20 is a plate-shaped metal member processed into a predetermined shape, and comprises a base material and a plating layer formed on its surface.

[0018] Examples of base material include metals selected from copper, aluminum, silver, gold, zinc, chromium, tungsten, cobalt, nickel, iron, magnesium, rhodium, ruthenium, etc., or alloys thereof. These may be single layers or laminated structures (e.g., clad materials). Metal plates containing 90% or more copper as the main component are preferred. Trace elements such as silicon or phosphorus (nonmetals) may also be included.

[0019] The maximum thickness of the substrate is preferably, for example, 100 μm to 800 μm, and more preferably 150 μm to 200 μm.

[0020] For the plating layer placed on the surface of the substrate, a material with a higher reflectivity than the substrate is preferred. Examples of plating layers include nickel, silver, gold, platinum, palladium, aluminum, tungsten, molybdenum, ruthenium, and rhodium. Examples of laminated structures include Ni / Pd / Au, Ni / Pt / Au, and Ni / Au / Ag, with Ni / Pd / Au being particularly preferred.

[0021] The thickness of the plating layer is preferably between 1 μm and 10 μm, and more preferably between 1.5 μm and 6 μm.

[0022] The conductive member 20 comprises an upper surface 20U, a lower surface 20L opposite to the upper surface 20U, and a side surface 20S between the upper surface 20U and the lower surface 20L. The upper surface 20U of the first conductive member 21 and the upper surface 20U of the second conductive member 22 are flat surfaces that are positioned on the same plane and are not exposed to the outside.

[0023] The upper surface 20U of the first conductive member 21 and the upper surface 20U of the second conductive member 22 may be entirely flat surfaces, or, as shown in Figures 2A to 2C, they may have a machined portion 20P in addition to being flat surfaces.

[0024] When heated, the solder 30 melts and spreads between the conductive member 20 and the electrodes 12 of the light-emitting element 10, and then hardens when cooled, joining the conductive member 20 and the light-emitting element 10. Depending on how the molten solder 30 spreads, the light-emitting element 10 may move to an unintended position. Therefore, by placing a processed area 20P on the upper surface 20U of the conductive member 20 as a part with poor wettability of the solder 30, the spreading of the solder 30 can be controlled. As shown in Figure 2A, in a plan view, the processed area 20P can be placed on the outer circumference and / or near the electrodes 12 of the light-emitting element 10.

[0025] The processed portion 20P is concave, convex, or uneven in cross-sectional view. The height of the processed portion, i.e., the height or depth from the flat portion of the upper surface 20U of the conductive member 20, can be, for example, 1 μm or more and 10 μm or less. The width of the processed portion 20P (width in the direction perpendicular to the stretching direction) can be, for example, 10 μm or more and 100 μm or less in plan view.

[0026] The processed portion 20P can be formed on the flat upper surface 20U by, for example, irradiating it with laser light. Alternatively, the processed portion 20P can be formed by pressing with a mold, etching, blasting, or the like.

[0027] For example, when applying a layered plating structure with a copper outer layer and nickel in the underlying layer to the surface of a copper-based substrate of conductive member 20, irradiating it with laser light to form a processed area 20P can create an uneven structure in which nickel is exposed from the gold in all or part of the processed area 20P. The wettability between solder 30 and nickel is worse than the wettability between solder 30 and gold. Therefore, the exposure of nickel can effectively reduce the flow of solder 30 to unintended areas.

[0028] Furthermore, if the surface of the processed area formed by irradiation with laser light has both gold and nickel, the solder 30 has low wettability with nickel but high wettability with gold, so the solder 30 spreads wet on the gold of the processed area 20P. In this way, the contact area increases as a part of the uneven processed area 20P comes into contact with the solder 30, thereby improving the adhesion between the solder 30 and the conductive member 20. Also, in the light-emitting device 100A shown in Figure 1B, a part of the uneven processed area 20P comes into contact with the support member 50, increasing the contact area between the conductive member 20 and the support member 50. This improves the adhesion between the conductive member 20 and the support member 50. Similarly, in the light-emitting device 100D shown in Figure 3, a part of the uneven processed area 20P comes into contact with the translucent member 40, increasing the contact area between the conductive member 20 and the translucent member 40. This improves the adhesion between the conductive member 20 and the translucent member 40.

[0029] In the example shown in Figure 2A, the processing section 20P is positioned along the outer circumference of the electrode 12 of the light-emitting element 10. The processing section 20P1 may be continuous or separated at any point on the outer circumference of the electrode 12. By positioning the processing section 20P to surround the outer circumference of the pair of conductive members 20 in this way, it is possible to reduce the movement of the light-emitting element 10 to an unintended position when the solder 30 melts. This allows the light-emitting element 10 to be positioned with high positional accuracy.

[0030] Furthermore, the processing portion 20P2, which is positioned around the protective element 70, extends in a direction parallel to the short side of the electrode 12 of the light-emitting element 10, and is positioned to sandwich the protective element 70. This reduces the movement of the protective element 70 toward the light-emitting element 10 when the solder 30 melts. In particular, in a plan view, by positioning the processing portion 20P2, which is positioned between the light-emitting element 10 and the protective element 70, away from the outer circumference of the protective element 70, the movement of the protective element 70 toward the light-emitting element 10 when the solder 30 melts can be further reduced. Alternatively, the processing portion 20P2 may be positioned to surround the outer circumference of the protective element 70 in a plan view, similar to the processing portion 20P1.

[0031] The lower surface 20L of the first conductive member 21 and the lower surface 20L of the second conductive member 22 are flat surfaces that are positioned on the same plane and are exposed to the outside.

[0032] (Solder) The solder 30 is a conductive material that electrically connects the positive and negative pair of electrodes 12 of the light-emitting element 10 to the conductive member 20. One of the electrodes 12 of the light-emitting element 10 is electrically joined to the first conductive member 21 via the solder 30, and the other of the electrodes 12 of the light-emitting element 10 is electrically joined to the second conductive member 22 via the solder 30.

[0033] The solder 30 is positioned so as to be in contact with the lower surface 12BL of the base portion 12B and the lower surface 12EL of the extended portion 12E of the electrode 12 of the light-emitting element 10. Furthermore, the solder 30 may also be positioned on the upper surface 12EU of the extended portion 12E. The thickness of the solder 30 between the base portion 12B of the electrode 12 and the upper surface 20U of the conductive member 20 can be 5 μm or more and 20 μm or less. In addition, the thickness of the solder 30 between the furthest part of the lower surface 12EL of the extended portion 12E and the upper surface 20U of the conductive member 20 can be 0.01 μm or more and 20 μm or less. On the upper surface 12EU of the extended portion 12E, the thickness of the solder 30 can be 0.01 μm or more and 10 μm or less.

[0034] Examples of materials for solder 30 include Au-Sn, Sn-Ag-Cu, Sn-Cu, Sn-Sb, Sn-Bi, Sn-In, Sn-Pb, and Ni-Sn.

[0035] (light-emitting element) The light-emitting device comprises one or more light-emitting elements 10. The light-emitting elements 10 can be semiconductor light-emitting elements such as light-emitting diodes. The light-emitting element 10 comprises a semiconductor laminate 11 and a pair of positive and negative electrodes 12. The semiconductor laminate 11 comprises, for example, an element substrate such as sapphire and a semiconductor layer formed thereon. Alternatively, the semiconductor laminate 11 may consist only of semiconductor layers without an element substrate. The planar shape of the light-emitting element 10 can be a polygon such as a triangle, square, or hexagon. The size of the light-emitting element 10 can be, for example, a square with sides of 100 μm or more and 3000 μm or less in plan view. Specifically, it can be a square with sides of approximately 600 μm, 1000 μm, 1400 μm, or 1800 μm. The light-emitting element 10 may also be a rectangle with long and short sides in plan view. For example, it can be 1100 μm × 200 μm in size. When multiple light-emitting elements 10 are provided, the size, emission wavelength, composition, etc. of each light-emitting element 10 may be the same, or some or all of them may be different. Furthermore, all of the multiple light-emitting elements 10 can be connected in series or in parallel, or they can be connected in a mixed series and parallel configuration.

[0036] The semiconductor laminate 11 includes an n-type semiconductor layer, a p-type semiconductor layer, and a light-emitting layer sandwiched between them. Such a semiconductor laminate including a light-emitting layer is, for example, made of In x Al y Ga 1-x-y It can include N(0≦x, 0≦y, x+y≦1).

[0037] The semiconductor laminate 11 may have a structure that includes one or more light-emitting layers between an n-type semiconductor layer and a p-type semiconductor layer, or it may have a structure in which a structure containing an n-type semiconductor layer, a light-emitting layer, and a p-type semiconductor layer in sequence is repeated multiple times. When the semiconductor laminate 11 includes multiple light-emitting layers, it may include light-emitting layers with different emission peak wavelengths, or it may include light-emitting layers with the same emission peak wavelength. Note that "the same emission peak wavelength" includes cases where there is a variation of several nanometers. The combination of emission peak wavelengths between the multiple light-emitting layers can be selected as appropriate. For example, when the semiconductor laminate includes two light-emitting layers, the light-emitting layers can be selected in combinations such as blue light and blue light, green light and green light, red light and red light, ultraviolet light and ultraviolet light, blue light and green light, blue light and red light, or green light and red light.

[0038] The light-emitting element 10 is provided with at least one pair of electrodes 12 on the lower side of the semiconductor laminate 11. In other words, one light-emitting element 10 is provided with at least one positive electrode and at least one negative electrode as electrodes 12. In the light-emitting device 100A shown in Figure 1A, there is one positive electrode and one negative electrode each in the light-emitting element 10. The positive electrode and the negative electrode are both rectangular in plan view. When there is only one positive electrode and one negative electrode, their respective sizes can be increased. This increases the contact area with the solder 30, thereby improving heat dissipation.

[0039] Each electrode 12 comprises a base portion 12B and an extended portion 12E. The hatched area in Figure 1A indicates the extended portion 12E. As shown in Figure 1A, it is preferable that the extended portion 12E be arranged around the entire periphery of the base portion 12B. The height of the extended portion 12E, i.e., the height from the lower surface 12BL of the base portion 12B to the upper surface 12EU of the extended portion 12E, can be, for example, 5% to 50% of the height of the base portion 12B, i.e., the height from the lower surface 12BL of the base portion 12B to the lower surface of the semiconductor laminate 11. The width of the extended portion 12E, i.e., the length from the side surface of the base portion 12B to the end of the upper surface 12EU of the extended portion 12E, can be, for example, 1% to 10% of the width of the base portion 12B. This reduces the risk of each electrode 12 coming into contact with each other.

[0040] Furthermore, from another perspective, in a plan view, the area of ​​the extended portion 12E can be 5% to 40% of the area of ​​the base portion 12B. This ensures sufficient heat dissipation.

[0041] In the two electrodes 12, the distance between each extended portion 12E is preferably shorter than the distance between the upper surfaces 20U of the conductive member 20, for example, it can be 10 μm or more and 100 μm or less. This allows the heat generated in the light-emitting element 10 to be efficiently dissipated to the conductive member 20.

[0042] The electrodes 12 of the light-emitting element 10 can be made of electrically conductors, such as gold, silver, copper, platinum, iron, nickel, or alloys thereof. The electrodes 12 may include an ohmic electrode that contacts the lower surface of the semiconductor laminate 11 and a pad electrode that is connected to the ohmic electrode and connected to the outside. The base portion 12B and the extended portion 12E of the electrodes 12 correspond to the pad electrode. The thickness of the electrodes 12 can be, for example, 0.5 μm or more and 100 μm or less, more preferably 5 μm or more and 50 μm or less.

[0043] (Translucent member) The light-transmitting member 40 is a light-transmitting member placed on the upper surface of the semiconductor laminate 11 of the light-emitting element 10. Light emitted from the light-emitting element 10 is emitted to the outside through the light-transmitting member 40. In the light-emitting devices 100A, 100B, and 100C, the light-transmitting member 40 is plate-shaped, and a pre-formed light-transmitting member 40 can be joined using a bonding member 60 or the like. Alternatively, the light-transmitting member 40 and the light-emitting element 10 can be directly joined by a direct bonding method without using a bonding member 60. Furthermore, as shown in the light-emitting device 100D, the light-transmitting member 40 may be placed so as to be in contact not only with the upper surface of the light-emitting element 10 but also with the side surface. Such a light-transmitting member 40 can be formed by placing the light-emitting element 10 in a recess R with a support member 50 as a wall, then placing an uncured light-transmitting member 40, and then curing it by heating or the like. Note that "uncured" refers to a state in which it can flow, and includes not only those that have not cured at all but those that have been partially cured.

[0044] The light-transmitting member 40 can be a resin member, an inorganic member, glass, or a combination thereof. Preferably, the light-transmitting member 40 has a transmittance of 60% or more of light at the peak wavelength of the light emitted from the light-emitting element 10, more preferably 70% or more, and even more preferably 80% or more.

[0045] The translucent member 40 can be made from thermosetting resins such as silicone resin, silicone-modified resin, epoxy resin, and phenolic resin, or from thermoplastic resins such as polycarbonate resin, acrylic resin, methylpentene resin, and polynorbornene resin. Silicone resin is particularly preferred due to its excellent light resistance and heat resistance. The translucent member 40 can be made from inorganic materials such as silicon oxide and aluminum oxide. As for the glass, alkali-free glass, soda glass, soda-lime glass, borosilicate glass, aluminosilicate glass, quartz glass, and low-alkali borosilicate glass can be used.

[0046] The translucent member 40 may consist solely of the translucent member described above, or it may be a translucent member used as a base material and containing a phosphor and / or light scattering agent that is excited by light from the light-emitting element and converted into light of a different wavelength. In the case of a plate-shaped translucent member 40 as shown in Figure 1B, it may be a laminated structure in which the translucent member described above is used as a base material and a phosphor and / or light scattering agent is arranged on its surface. In the case of a translucent member 40 placed in a recess R as shown in Figure 3, the phosphor or light scattering agent may be dispersed throughout the entire structure, or it may be concentrated towards the bottom of the recess R.

[0047] Examples of phosphors that can be used include yttrium-aluminum-garnet phosphors, lutetium-aluminum-garnet phosphors, terbium-aluminum-garnet phosphors, CCA phosphors, SAE phosphors, chlorosilicate phosphors, silicate phosphors, oxynitride phosphors such as β-sialon phosphors or α-sialon phosphors, nitride phosphors such as LSN phosphors, BSESN phosphors, SLA phosphors, CASN phosphors or SCASN phosphors, fluoride phosphors such as KSF phosphors, KSAF phosphors or MGF phosphors, quantum dots having a perovskite structure, group II-VI quantum dots, group III-V quantum dots, or quantum dots having a chalcopyrite structure.

[0048] Examples of light scattering agents that can be used include particles of titanium dioxide, silicon dioxide, aluminum oxide, zinc oxide, magnesium oxide, zirconium oxide, yttrium oxide, calcium fluoride, magnesium fluoride, niobium pentoxide, barium titanate, tantalum pentoxide, barium sulfate, or glass.

[0049] The translucent member 40 can be formed by placing a pre-molded plate-shaped member onto the light-emitting element 10 using a translucent bonding member 60, as shown in Figure 1B. In the example shown in Figure 1B, the bonding member 60 is thinly positioned between the light-emitting element 10 and the translucent member 40 and is in contact with the side surface of the light-emitting element 10. Alternatively, the light-emitting element 10 and the translucent member 40 can be directly bonded by a direct bonding method without using a bonding member. Furthermore, a liquid resin material can be placed on the light-emitting element 10 and then cured to form the translucent member 40. Alternatively, a thin film of the translucent member 40 can be placed on the light-emitting element 10 using a film formation method such as sputtering, vapor deposition, or atomic deposition, as shown in Figure 3.

[0050] The plate-shaped translucent member 40 shown in Figure 1B, etc., can have an area in plan view that is the same as the area of ​​the light-emitting element 10, or an area that is larger than the area of ​​the light-emitting element 10. Furthermore, it is preferable that the translucent member 40 overlaps the entire surface of the light-emitting element 10 in plan view. For example, the translucent member 40 can overlap the entire surface of the light-emitting element 10 in plan view and have an area larger than the light-emitting element 10. A translucent member 40 larger than the light-emitting element 10 can continuously cover the light-emitting element 10 and the support member 50 in top view. The sides of the translucent member 40 may be in contact with and covered by the support member 50, or they may be exposed from the support member 50.

[0051] (Support member) First, let's describe the case where a plate-shaped translucent member 40 is provided, as in the light-emitting device 100A shown in Figure 1B, etc. In such a light-emitting device 100, the support member 50 is positioned in contact with the upper surface 20U of the first conductive member 21 and the upper surface 20U of the second conductive member 22. The support member 50 is also positioned to the side of the light-emitting element 10. More specifically, it can cover the side surface of the light-emitting element 10 in contact with it. Alternatively, if a joining member 60 that joins the translucent member 40 and the light-emitting element 10 is in contact with a part of the side surface of the light-emitting element 10, the support member 50 indirectly covers the side surface of the light-emitting element 10 via the joining member 60. The support member 50 is also in contact with the lower surface of the semiconductor laminate 11 of the light-emitting element 10 and the side surface of the electrode 12. Furthermore, the support member 50 is also in contact with the solder 30. The support member 50 is also in contact with the side surface of the translucent member 40.

[0052] In the case of the light-emitting device 100D shown in Figure 3, the support member 50 is also positioned to the side of the light-emitting element 10. More specifically, the support member 50 is positioned to the side of the light-emitting element 10 and is arranged to surround the light-emitting element 10 in a top view. Together with the conductive member 20, the support member 50 forms a recess R in which the light-emitting element 10 and the light-transmitting member 40 can be placed.

[0053] The support member 50 can be light-reflective, light-absorbing, or light-transmitting. A resin material can be used as the base material of the support member 50. As the resin material, thermosetting resins such as silicone resin, silicone-modified resin, epoxy resin, and phenolic resin, and thermoplastic resins such as polycarbonate resin, acrylic resin, methylpentene resin, and polynorbornene resin can be used. Silicone resin, which has excellent light resistance and heat resistance, is particularly preferred.

[0054] In the case of a structure like the light-emitting device 100A shown in Figure 1B, if a resin member is used as the support member 50, the light-emitting element 10 and the conductive member 20 can be joined with solder 30, and then the support member 50 can be molded by compression molding, transfer molding, etc. In this case, the support member 50 may be molded using a pre-molten resin member, or a powdered resin member may be placed to cover the light-emitting element 10 and the conductive member 20, etc., and then molded by compression molding.

[0055] In the case of a structure like the light-emitting device 100D shown in Figure 3, it can be formed as a package with a recess R together with the conductive member 20 by molding by compression molding, transfer molding, etc.

[0056] The support member 50 may contain light-reflecting materials such as titanium oxide or zinc oxide. Alternatively, the support member 50 may contain light-absorbing materials such as carbon black or titanium black. The support member 50 may contain both light-reflecting and light-absorbing materials. In that case, both light-reflecting and light-absorbing materials can be contained in a single base material. Alternatively, the support member 50 may comprise a first light-reflecting support member in contact with the light-emitting element 10, and a second light-absorbing support member on the outside of the first support member.

[0057] Furthermore, the support member 50 may be composed of an inorganic material, such as boron nitride or alkali metal silicate. In this case, it may further contain titanium oxide or zirconium oxide.

[0058] Furthermore, the support member 50 may comprise both a resin material and an inorganic material.

[0059] If the support member 50 is light-reflective, it is preferable that the reflectance for light at the emission peak wavelength of the light emitted from the light-emitting element 10 is 70% or more, more preferably 80% or more, and even more preferably 90% or more.

[0060] (Protective element) The light-emitting device 100 may include a protective element 70. For example, the protective element 70 may be positioned on the upper or lower surfaces of the first conductive member 21 and the second conductive member 22, straddling them via solder 30. Alternatively, the protective element 70 may be positioned on the upper surface 20U of the first conductive member 21 and electrically connected to the second conductive member 22 via a wire. The protective element is connected in parallel with the light-emitting element 10. In the case of a protective element with polarity, such as a Zener diode, it is connected in the opposite direction to the light-emitting element 10. In the case of a protective element without polarity, such as a varistor, it is connected in the forward or reverse direction to the light-emitting element 10.

[0061] The protective element 70 comprises an element portion 71 and an electrode 72 positioned on the lower surface of the element portion 71. The electrode 72 of the protective element 70 may have a base portion 72B and an extended portion 72E extending laterally from the base portion 72B, similar to the electrode 12 of the light-emitting element 10. This makes it easier to disperse thermal stress, similar to the light-emitting element 10, and reduces the load on the element portion 71.

[0062] The lower surface 72L of the extended portion 72E of the electrode 72 of the protective element 70 includes the lower surface 72BL of the base 72B and the lower surface 72EL of the extended portion 72E. It is preferable that the extended portion 72E is arranged around the entire periphery of the base 72B. The height of the extended portion 72E, i.e., the height from the lower surface 72BL of the base 72B to the upper surface 72EU of the extended portion 72E, can be, for example, 5% to 50% of the height of the base 72B, i.e., the height from the lower surface 72BL of the base 72B to the lower surface of the element portion 71. The width of the extended portion 72E, i.e., the length from the side surface of the base 72B to the end of the upper surface 72EU of the extended portion 72E, can be, for example, 1% to 10% of the width of the base 72B. This can reduce the risk of the electrodes of the protective element coming into contact with each other.

[0063] The following describes the manufacturing method of the light-emitting element 10 and the manufacturing method of the light-emitting device 100 shown in Figure 1A, etc.

[0064] First, the manufacturing method of the light-emitting element 10 will be described. As shown in Figure 4A, a structure is prepared in which a semiconductor laminate 11 is placed on an adhesive sheet S1. At this point, the semiconductor laminate 11 is not yet separated into individual pieces but is in wafer form. A mask M is placed on the semiconductor laminate 11. For example, a mask M of a predetermined shape can be formed at a predetermined position by placing a photoresist on the semiconductor laminate 11 and performing exposure and development. The thickness of the mask M is set to be the thickness corresponding to the distance between the upper surface 12EU of the stretched portion 12E of the electrode 12 and the lower surface of the semiconductor laminate 11.

[0065] Next, as shown in Figure 4B, an electrode 12 made of plating is formed on the semiconductor laminate 11 exposed from the mask M by electroplating or electroless plating. At this time, the plating is made thicker than the thickness of the mask M by adjusting the immersion time of the structure in the plating solution. This makes it possible to form an electrode 12 having a base portion 12B formed on the part exposed from the mask M and an extended portion 12E formed on the mask M. The lower surface 12EL (the surface facing upward in Figure 2C) of the extended portion 12E formed on the mask M has a curved edge because the plating is formed laterally from the base portion 12B.

[0066] Next, as shown in Figure 4C, the mask M is removed. Then, the material is separated into individual pieces by laser scribing or the like. The separated light-emitting elements 10 are transferred onto a separately prepared adhesive sheet S2, as shown in Figure 4D. The adhesive sheet S2 and the electrode 12 are positioned facing each other. By going through these steps, the stretched portion 12E light-emitting element 10 can be formed.

[0067] Next, a method for manufacturing the light-emitting device 100 will be described. As shown in Figure 5A, a conductive member 20 is prepared. The conductive member 20 may be prepared by purchasing a conductive member 20 that has been pre-processed into a predetermined shape, or by purchasing a metal plate and processing it into a predetermined shape. Alternatively, a conductive member 20 having a processed portion 20P as shown in Figure 2A may be prepared by purchasing a conductive member 20, or a conductive member 20 or metal plate without a processed portion 20P may be purchased and the processed portion 20P may be formed to prepare the conductive member 20. At this point, the conductive member 20 is an assembly that includes parts that will become multiple light-emitting devices 100.

[0068] Solder 30 is placed on the upper surface 20U of the conductive member 20. In the example shown in Figure 5A, multiple solders 30 are placed for each electrode 12. This is to form the solder 30 with a uniform thickness so that the light-emitting element 10 is positioned parallel to the conductive part 20 in order to obtain good light distribution characteristics.

[0069] Next, heating causes the solder 30 to melt and spread over the entire lower surface 12L of the electrode 12 of the light-emitting element 10, including the lower surface 12BL of the base 12B and the lower surface 12EL of the extended portion 12E. Depending on the amount of solder 30, the solder may also spread to the upper surface 12EU of the extended portion 12E, as shown in Figure 1C. In this way, the light-emitting element 10 and the conductive member 20 can be joined with solder 30.

[0070] Next, as shown in Figure 5C, the uncured bonding member 60 is placed on the upper surface of the light-emitting element 10 by pin transfer or the like. Then, as shown in Figure 5D, the translucent member 40 is placed on the bonding member 60 and heated. This allows the light-emitting element 10 and the translucent member 40 to be bonded via the bonding member 60. At this time, the bonding member 60 placed on the upper surface of the light-emitting element 10 hangs down to cover the sides of the light-emitting element 10.

[0071] Next, as shown in Figure 5E, the uncured support member 50 is positioned so that the upper surface of the translucent member 40 and the lower surface 20L of the conductive member 20 are exposed, and then heated. This allows the support member 50 to be positioned to the side of the light-emitting element 10 and the translucent member 40. The support member 50 can be formed by compression molding, transfer molding, or the like. Finally, by cutting the support member 50 and the conductive member 20 with a cutting blade or the like, the individual light-emitting devices 100 can be obtained as shown in Figure 5F.

[0072] Examples of the present invention are as follows:

[0073] (Note 1) A pair of conductive members, Solder, which is arranged on the upper surfaces of the pair of conductive members, A light-emitting element comprising a semiconductor laminate and a pair of electrodes disposed on the lower surface of the semiconductor laminate, wherein the upper surface of the pair of conductive members and the lower surface of the pair of electrodes are joined via solder, A light-transmitting member is placed on the light-emitting element, A support member positioned to the side of the light-emitting element, Equipped with, Each of the pair of electrodes comprises a base portion and an extended portion that extends laterally from the side surface of the base portion, the extended portion having a curved lower surface. The solder is in contact with the lower surface of the extended portion, and is a light-emitting device. (Note 2) The light-emitting device according to Appendix 1, wherein the distance between the extended portions of the pair of electrodes is smaller than the distance between the pair of conductive members. (Note 3) The light-emitting device according to Appendix 1 or Appendix 2, wherein the height from the lower surface of the base of the electrode to the upper surface of the extended portion is 5% or more and 50% or less of the height from the lower surface of the electrode to the lower surface of the semiconductor laminate. (Note 4) The light-emitting device according to any one of the appendices 1 to 3, wherein the length from the side surface of the base to the end of the upper surface of the extension is 1% or more and 10% or less of the width of the base. (Note 5) The light-emitting device according to any one of the appendices 1 to 4, wherein the extended portion, in a plan view, is 5% to 40% of the area of ​​the base. (Note 6) The light-emitting device according to any one of Appendix 1 to Appendix 5, wherein the upper surface of the conductive member has a processed portion on the outer circumference and / or near the electrode in a plan view. (Note 7) The conductive member comprises a base material and a plating layer disposed on the surface of the base material. The aforementioned plating layer has a laminated structure in which the outermost surface is gold and nickel is provided in the layer below the gold. The light-emitting device according to Appendix 6, wherein in the processed portion, a portion of the nickel is exposed from the gold. [Explanation of Symbols]

[0074] 100... Light-emitting device 10…Light-emitting element 11… Semiconductor stack 12...Electrode 12B...Base (12BL...Underside of the base) 12E...Extended part (12EL...Bottom surface of the extended part, 12EU...Top surface of the extended part) 20...Conductive member (20U...Top surface, 20L...Bottom surface, 20S...Side surface, 20P...Processed part) 21…First conductive member 22...Second conductive member 30... solder 40...Translucent member 50…Support member 60…Jointing member 70…Protective element 71... Element section 72...electrode (72B...base, 72E...extension part) S1, S2... Adhesive sheets M... Mask R... recess

Claims

1. A pair of conductive members, Solder, which is arranged on the upper surfaces of the pair of conductive members, A light-emitting element comprising a semiconductor laminate and a pair of electrodes disposed on the lower surface of the semiconductor laminate, wherein the upper surface of the pair of conductive members and the lower surface of the pair of electrodes are joined via solder, A light-transmitting member is placed on the light-emitting element, A support member positioned to the side of the light-emitting element, Equipped with, Each of the pair of electrodes comprises a base portion and an extended portion that extends laterally from the side surface of the base portion, the extended portion having a curved lower surface. The solder is in contact with the lower surface of the extended portion, and is a light-emitting device.

2. The light-emitting device according to claim 1, wherein the distance between the extended portions of the pair of electrodes is smaller than the distance between the pair of conductive members.

3. The light-emitting device according to claim 1, wherein the height from the lower surface of the base of the electrode to the upper surface of the extended portion is 5% or more and 50% or less of the height from the lower surface of the electrode to the lower surface of the semiconductor laminate.

4. The light-emitting device according to claim 1, wherein the length from the side surface of the base to the end of the upper surface of the extension is 1% or more and 10% or less of the width of the base.

5. The light-emitting device according to claim 1, wherein the extended portion has an area of ​​5% or more and 40% or less of the base portion in a plan view.

6. The light-emitting device according to claim 1, wherein the upper surface of the conductive member has a processed portion on the outer circumference and / or near the electrode in a plan view.

7. The conductive member comprises a base material and a plating layer disposed on the surface of the base material. The aforementioned plating layer has a laminated structure in which the outermost surface is gold and nickel is provided in the layer below the gold. The light-emitting device according to claim 6, wherein in the processed portion, a portion of the nickel is exposed from the gold.

Images