Light emitting device

Abstract

The invention provides a light-emitting device which is small in size and high in reliability. The light-emitting device includes: a package including a light-emitting element having a first surface and a second surface opposite to the first surface, a first light-transmitting member disposed on the second surface side of the light-emitting element, a pair of electrodes disposed on the first surface side of the light-emitting element, and a first cover member disposed on the first surface side of the light-emitting element and covering the first surface side of the light-emitting element; a first cover member that covers the light-emitting element such that the pair of electrodes are exposed; a light guide plate on which the package is disposed; a second cover member that covers the light guide plate and covers a side of the package; and a pair of wirings which continuously cover the exposed pair of electrodes and the first cover member and are respectively connected to the pair of electrodes, the pair of wirings being a mixture of a resin and a metal powder and having conductivity, and having laser irradiation spots between the pair of electrodes.

Description

[0001] This application is a divisional application of the invention patent application with application number 202010076080.4, invention name “Method for manufacturing a light-emitting device”, and application date January 22, 2020 (the earliest priority date is January 29, 2019). Technical Field

[0002] The present invention relates to a light emitting device. Background Art

[0003] Instead of providing a housing for housing a light-emitting element, the following small light-emitting device is known: a sealing member including a reflective material is used to cover the side and lower surface of the light-emitting element, and a plated electrode is provided that is in contact with the lower surface of a bump electrode of the light-emitting element and the lower surface of the sealing member (for example, Patent Document 1).

[0004] Furthermore, there is known a method for manufacturing a light emitting device, in which a metal layer is formed to continuously cover a pair of electrodes and a covering member, and a portion of the metal layer is removed by irradiating with laser light (for example, Patent Document 2).

[0005] Prior Art Literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent Application Publication No. 2012-124443

[0008] Patent Document 2: Japanese Patent Application Publication No. 2017-118098 Summary of the invention

[0009] -Problems to be solved by the invention-

[0010] The present invention provides a small-sized and highly reliable light-emitting device and a method for manufacturing the same.

[0011] -Methods for solving problems-

[0012] The manufacturing method of the light-emitting device involved in the embodiment of the present invention includes: a process of preparing an intermediate, which comprises: a light-emitting element, which comprises a pair of electrodes on the first surface side; and a first covering member, which covers the light-emitting element so that a portion of the surface of the pair of electrodes is exposed; a process of forming a metal paste layer, which continuously covers the exposed pair of electrodes and the first covering member; and a process of forming a pair of wirings, which irradiates the metal paste layer on the pair of electrodes and the metal paste layer on the first covering member with laser, and removes a portion of the metal paste layer between the pair of electrodes and the metal paste layer on the first covering member, so that the pair of electrodes are not short-circuited.

[0013] -Effects of the Invention-

[0014] As described above, it is possible to provide a method for manufacturing a small-sized light-emitting device with high reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1A It is a schematic perspective view of the package according to the embodiment as seen obliquely from above.

[0016] Figure 1B It is a schematic bottom view of the package according to the embodiment.

[0017] Figure 1C It is a schematic cross-sectional view of a package according to an embodiment.

[0018] Figure 2A It is a schematic cross-sectional view for explaining a method for manufacturing a light emitting device according to an embodiment.

[0019] Figure 2B It is a schematic cross-sectional view for explaining a method for manufacturing a light emitting device according to an embodiment.

[0020] Figure 2C It is a schematic cross-sectional view for explaining a method for manufacturing a light emitting device according to an embodiment.

[0021] Figure 2D It is a schematic cross-sectional view for explaining a method for manufacturing a light emitting device according to an embodiment.

[0022] Figure 2E It is a schematic cross-sectional view for explaining a method for manufacturing a light emitting device according to an embodiment.

[0023] Figure 3A It is a schematic bottom view for explaining the method for manufacturing the light emitting device according to the embodiment.

[0024] Figure 3B It is a schematic bottom view for explaining the method for manufacturing the light emitting device according to the embodiment.

[0025] Figure 3C It is a schematic bottom view for explaining the method for manufacturing the light emitting device according to the embodiment.

[0026] Figure 3D It is a schematic bottom view for explaining the method for manufacturing the light emitting device according to the embodiment.

[0027] Figure 4A It is a schematic plan view of a light emitting device according to an embodiment.

[0028] Figure 4B It is a schematic perspective view of a light emitting device according to an embodiment.

[0029] Figure 5It is a schematic perspective view of the light emitting device according to the second embodiment when viewed from the light guide plate side.

[0030] Figure 6 It is a schematic cross-sectional view of a light emitting device according to a second embodiment.

[0031] Figure 7 It is a schematic plan view of a light emitting device according to a second embodiment.

[0032] Figure 8 It is a schematic plan view of a light emitting device according to a third embodiment.

[0033] Fig. 9 It is a schematic cross-sectional view of a light emitting device according to a fourth embodiment.

[0034] Fig. 10A It is a schematic diagram schematically showing a modification of the package of each embodiment.

[0035] Fig. 10B It is a schematic diagram schematically showing a modification of the package of each embodiment.

[0036] Fig.11 It is a schematic cross-sectional view of a light emitting device according to a fifth embodiment.

[0037] Fig.12 This is a schematic cross-sectional view of a light emitting device according to a sixth embodiment.

[0038] Fig.13 This is a schematic cross-sectional view of a light emitting device according to a seventh embodiment.

[0039] -Explanation of symbols-

[0040] 1 Light-emitting element

[0041] 2. First covering member

[0042] 3. First light-transmitting member

[0043] 4. Second light-transmitting member

[0044] 5 Electrodes

[0045] 5a 1st electrode

[0046] 5b Second electrode

[0047] 10 Package

[0048] 13. 1st light reflection film

[0049] 14 Second light reflection film

[0050] 15. Third light reflection film

[0051] 20, 21, 22, 91 Wiring

[0052] 20a, 21a, 91a 1st wiring

[0053] 20b, 21b, 91b Second wiring

[0054] 21c, 22c wide section

[0055] 22d Wiring Department

[0056] 25 Metal paste layer

[0057] 30, 31 Light guide plate

[0058] 31a 1st recess

[0059] 31b 2nd concave part

[0060] 31c 3rd recess

[0061] 40 Third light-transmitting member

[0062] 50 Second covering member

[0063] 60 Insulation components

[0064] 60a Insulation film

[0065] 60b Auxiliary insulating film

[0066] 70 Reflection member

[0067] 80 Shading member

[0068] 90 Wiring substrate

[0069] 100 Light emitting device. DETAILED DESCRIPTION

[0070] Hereinafter, embodiments of the present invention will be described in detail based on the accompanying drawings. In addition, in the following description, terms indicating specific directions and positions (for example, "up", "down", "right", "left" and other terms containing these terms) are used as needed. These terms are used to facilitate the understanding of the invention with reference to the accompanying drawings, and the technical scope of the present invention is not limited according to the meaning of these terms. In addition, parts with the same symbols appearing in multiple drawings represent the same parts or components. In addition, with respect to resin components such as the first light-transmitting component, the second light-transmitting component, and the covering component, the same names are used for description regardless of before and after molding, curing, curing, and monolithicization. That is, for components whose states change according to the stage of the process, such as being liquid before molding, solid after molding, and then being divided into solids after molding to change the shape, the same names are used for description.

[0071] The package 10 according to the embodiment is shown in Figure 1A to Figure 1C . Figure 1A It is a schematic perspective view of the package according to the embodiment as seen obliquely from above. Figure 1B It is a schematic bottom view of the package according to the embodiment. Figure 1C is a schematic cross-sectional view of a package according to an embodiment of the present invention. Figure 1B The cross section at IC-IC of FIG. As an example of the intermediate body, the package 10 is used for description, but various forms can be adopted as long as the light emitting element 1 and the first covering member 2 are provided.

[0072] The package 10 includes a light emitting element 1, a first covering member 2, a first translucent member 3, a second translucent member 4, and a pair of electrodes 5. The package 10 is a rectangular parallelepiped, but may be any shape. The light emitting element 1 is rectangular when viewed from above, but may be a polygon such as a triangle, a pentagon, or a hexagon. The light emitting element 1 includes, for example, a first semiconductor layer, an active layer, and a second semiconductor layer on a substrate, and a portion of the active layer and the second semiconductor layer is removed. The light emitting element 1 has a first surface and a second surface opposite to the first surface, and has a pair of electrodes 5 on the first surface side. The so-called first surface side is intended to include not only the case where an electrode is directly formed in the light emitting element 1, but also the case where an electrode is indirectly formed via other components such as a semiconductor layer and a metal. The pair of electrodes 5 includes a first electrode 5a and a second electrode 5b with different polarities. The first electrode 5a is electrically connected to the first semiconductor layer, and the second electrode 5b is electrically connected to the second semiconductor layer. The first translucent member 3 is arranged on the second surface side of the light emitting element 1. When viewed from above, the size of the first light-transmitting member 3 may be larger than or the same as the second surface of the light-emitting element 1, or smaller than the second surface of the light-emitting element 1. When the size of the first light-transmitting member 3 is the same as or larger than the second surface of the light-emitting element 1, the second light-transmitting member 4 may be arranged on the side of the light-emitting element 1. When viewed from above, the first light-transmitting member 3 is rectangular, but may also be a polygon such as a triangle, a pentagon, or a hexagon. The second light-transmitting member 4 preferably plays a role in bonding the light-emitting element 1 to the first light-transmitting member 3. The first covering member 2 is provided to cover the first surface and the side surface of the light-emitting element 1, the first light-transmitting member 3, and the second light-transmitting member 4, so that the surface of the pair of electrodes 5 is exposed. The first covering member 2 may be formed by a single process, or may be formed by a plurality of processes of two or more times. When the first covering member 2 is formed by two or more processes, it may be provided as a multilayer, or may be provided as a single layer without an interface.

[0073] Using the above-mentioned package, a light-emitting device can be formed through the following steps. FIG. 2A to FIG. 2E2 is a schematic cross-sectional view for explaining a method for manufacturing a light emitting device according to an embodiment. As an example, two packages are shown, but the present invention is not limited to this, and a plurality of packages may be used. FIG. 3A to FIG. 3D It is a schematic bottom view for explaining the method for manufacturing the light emitting device according to the embodiment. Figure 4A It is a schematic plan view of a light emitting device according to an embodiment. Figure 4B It is a schematic perspective view of a light emitting device according to an embodiment. Figure 4A It shows the state before the light emitting device is singulated. Figure 4B It shows a light-emitting device after being singulated.

[0074] The manufacturing method of the light-emitting device involved in the embodiment includes: a process of preparing an intermediate, which comprises: a light-emitting element, which comprises a pair of electrodes on the first surface side; and a first covering member, which covers the light-emitting element so that a portion of the surface of the pair of electrodes is exposed; a process of forming a metal paste layer, which continuously covers the exposed pair of electrodes and the first covering member; and a process of forming a pair of wirings, irradiating the metal paste layer on the pair of electrodes and the metal paste layer on the first covering member with laser, and removing a portion of the metal paste layer between the pair of electrodes and the metal paste layer on the first covering member so that the pair of electrodes are not short-circuited.

[0075] By irradiating the metal paste layer with laser, laser ablation is generated, and a portion of the metal paste layer on the intermediate is removed. As a result, the metal paste layer is patterned, and the metal paste layer can be used as wiring or external connection electrodes. Laser ablation refers to the phenomenon that the surface of a solid is removed if the irradiation intensity of the laser irradiated to the surface of the solid is above a certain level (threshold). By using laser ablation, the metal paste layer can be patterned without using a mask, etc.

[0076] For example, when a metal layer is used to form wiring, sputtering, evaporation, and other processes are complex and require advanced equipment, which is costly. In addition, if the metal layer is a thin film, disconnection is likely to occur, so it is required to thicken the metal layer. On the other hand, when laser ablation is generated by irradiating a metal layer with a laser so that a short circuit does not occur to form heterogeneous electrodes, if the metal layer is thick, the laser output must be increased, or the melting and removal of the metal layer takes time, which requires improvement in operating efficiency.

[0077] In view of this, by using the metal paste layer in the embodiment, wiring can be formed simply and with high precision. In addition, the metal paste layer contains resin in a plurality of metal powders, so by irradiating the metal paste layer with laser, the resin is easily scattered, and the laser output can be greatly suppressed. In addition, the laser irradiation time can be greatly shortened, and the operating efficiency can be greatly improved. In addition, since the operating efficiency based on laser ablation can be greatly improved, the metal paste layer can be made thicker, and wire breakage can be difficult to occur. Furthermore, by using laser ablation to remove a portion of the metal paste layer, a groove with a thinner line width can be formed, and a smaller light-emitting device can be realized with high reliability.

[0078] A plurality of packages are arranged on the light guide plate, but the number is not particularly limited. For example, after arranging a plurality of packages on the light guide plate, they are singulated so that a total of 16 packages in 4 rows and 4 columns become one segment. A large display that can be expanded by electrically connecting each segment can be provided, and each segment can be replaced even if a part of it does not light up, so it can be easily replaced.

[0079] Hereinafter, each step will be described in detail.

[0080] (Process of preparing intermediates)

[0081] An intermediate body is prepared, which includes: a light emitting element 1 including a pair of electrodes 5 on a first surface side; and a first covering member 2 covering the light emitting element 1 with a portion of the surface of the pair of electrodes 5 exposed.

[0082] The package 10 is placed on the light guide plate 30. The package 10 is preferably arranged on the light guide plate 30 via the third light-transmitting member 40 having adhesiveness. The first light-transmitting member 3 of the package 10 is preferably arranged in contact with the light guide plate 30. The third light-transmitting member 40 preferably covers the side surface of the first light-transmitting member 3 and the side surface of the first covering member 2. This is because the light emitted from the light-emitting element 1 is diffused laterally. There are a plurality of packages 10 arranged on the light guide plate 30, and they are preferably arranged in a state of being regularly arranged in the longitudinal and transverse directions. The side of the package 10 arranged on the light guide plate 30 is preferably covered with the second covering member 50. The thickness of the second covering member 50 is preferably thinner than the thickness of the package 10, but it may be the same or thicker. This is to facilitate the formation of the metal paste layer 25 or the wiring 20. The pair of electrodes 5 preferably contain Cu. This is because the conductivity is good.

[0083] The light guide plate 30 may also be a flat plate, or a recess for arranging the package 10 may be provided in a portion of the flat plate. The recess is rectangular when viewed from above, preferably in a shape similar to the package 10, but may also be a polygon such as a triangle, a pentagon, or a hexagon. The depth of the recess may be the same as the height of the package 10, or may be shallower than the height of the package 10. The depth of the recess may also be shallower than the height of the package 10, so that a portion of the package 10 protrudes beyond the light guide plate 30 when viewed in cross section, and the side of the package 10 may be covered by the second covering member 50.

[0084] The distance between adjacent light emitting elements 1 can be appropriately selected according to the size of the target light emitting device 100 and the size of the light emitting element 1. However, since the cover member is cut into individual pieces in a subsequent process, the arrangement is also considered in consideration of the cutting margin (the width of the cutting blade) and the like.

[0085] A first covering member 2 is disposed on the first surface of the light-emitting element 1 and between a pair of electrodes 5. The spacing between the pair of electrodes 5 is preferably greater than 10 μm, and particularly preferably greater than 20 μm. In addition, the spacing between the pair of electrodes 5 is preferably less than 100 μm, and particularly preferably less than 50 μm. Thus, a pair of wirings can be easily formed by irradiation with a laser described later, and a small package 10 can be used. It is preferred to set the spacing between the electrodes 5 according to the spot diameter of the laser, and if the width does not cause a short circuit, the narrower side is preferred.

[0086] (Step of forming a metal paste layer)

[0087] A metal paste layer is formed to continuously cover the exposed pair of electrodes 5 and the first covering member 2 .

[0088] A plurality of packages 10 are arranged on the light guide plate 30, each package 10 is arranged across the third light-transmitting member 40, and a second covering member 50 is arranged on the side of the package 10. The metal paste layer 25 is arranged so as to continuously cover the first covering member 2 and the second covering member 50. The process of forming the metal paste layer 25 is preferably formed by any method of printing or spraying. Printing can use any method such as gravure printing, relief printing, lithographic printing, screen printing, etc., preferably screen printing. Spraying can use any method of inkjet, air distribution, and jet distribution. As a result, there is no need for high-level equipment such as sputtering and evaporation, and the metal paste layer 25 can be easily formed, thereby forming the wiring 20. The thickness of the metal paste layer 25 is preferably formed to be greater than 1 μm, preferably greater than 3 μm and less than 50 μm, and particularly preferably greater than 5 μm and less than 20 μm. By setting it to be greater than the specified thickness, conduction can be ensured and reliability can be improved. In addition, by making the metal paste layer 25 a specified thickness, resistance can be reduced. Thus, even when the metal paste layer 25 has a predetermined thickness, the wiring 20 can be easily formed by laser ablation. The metal paste layer 25 may have a width that allows conduction, and is preferably 200 μm to 1000 μm, and particularly preferably 400 μm to 700 μm.

[0089] In the process of preparing the intermediate, it is preferred to use a plurality of light emitting elements 1, in the process of forming the metal paste layer 25, the metal paste layer 25 continuously covers the plurality of light emitting elements 1, and in the process of forming the wiring 20 described later, the plurality of light emitting elements 1 are electrically connected. Thus, the plurality of light emitting elements 1 can be easily wired.

[0090] The metal paste layer 25 used here is preferably a mixture of resin and metal powder, and may also contain an organic solvent. The size of the metal powder is preferably greater than 0.01 μm and less than 10 μm, and particularly preferably greater than 0.1 μm and less than 5 μm. By controlling the size of the metal powder used in the metal paste layer 25, the conductivity can be improved. In addition, when printing the metal paste layer 25, the viscosity can be adjusted. Before the metal paste layer 25 is cured, the resin can be either powder or liquid.

[0091] The metal powder preferably includes at least one of silver powder, copper powder, or silver powder or copper powder covered with a metal film, thereby improving electrical conductivity.

[0092] The concentration of the metal powder in the metal paste layer 25 is preferably 60% by weight or more and 95% by weight or less. By increasing the concentration of the metal powder, the conductivity can be improved and the resistance can be suppressed to a low level. In addition, by setting the proportion of the resin to a predetermined range, printing can be easily performed.

[0093] (Process of forming a pair of wirings)

[0094] The metal paste layer 25 continuously covering the pair of electrodes 5 and the first covering member 2 is irradiated with laser light to remove a portion of the metal paste layer 25, thereby forming the first wiring 20a and the second wiring 20b that are the pair of wirings 20, so that the pair of electrodes 5 are not short-circuited. The first wiring 20a and the second wiring 20b are formed by cutting a portion of the metal paste layer 25, and no material different from the metal paste layer 25 is used. In addition, the metal paste layer 25 is removed by irradiating with laser light, so that the metal paste layer 25 is disconnected between the pair of electrodes 5 of one light-emitting element 1, and the first wiring 20a and the second wiring 20b that are the pair of wirings 20 are continuous with the metal paste layer 25 covering the electrodes 5 of the other adjacent light-emitting element 1. That is, the metal paste layer 25 between the electrodes 5 of one light-emitting element 1 is disconnected, and in the state where the metal paste layer 25 between the electrodes 5 of the other light-emitting element 1 is continuous, it does not function as a wiring for driving two light-emitting elements at the same time.

[0095] For example, the first wiring 20a and the second wiring 20b may be formed so that two light emitting elements 1 ( Figure 3A to Figure 3D ). The metal paste layer 25 is formed by printing or spraying the metal paste as a raw material, so that the resin contained in the metal paste layer 25 is cured. Curing can be performed using curing methods such as heating or laser irradiation. The cured metal paste layer 25 is irradiated with a laser. The laser is preferably pulsed, and the size of the laser spot diameter is appropriately adjusted. In addition, the number of pulse irradiations is also preferably within one to ten times, and particularly preferably within two to five times. By thickening the metal paste layer 25, the conductivity can be improved or the resistance can be reduced. On the other hand, in order to cut off the metal paste layer 25 without short-circuiting the first electrode 5a and the second electrode 5b, the number of pulse irradiations is increased. Since the process time for forming a pair of wirings 20 is lengthened by increasing the number of pulse irradiations, it is preferred that the number of pulse irradiations is small. Therefore, it is preferred to set the number of pulse irradiations to within two to five times. In addition, the same portion may be pulsed multiple times continuously, but in order to store heat, the laser may be moved and pulsed again after a specified time so that it is not continuously irradiated to the same portion. By using laser, micro-machining can be performed, and the positional accuracy of the cutting position can be maintained at a high level. Taking into account the thermal conductivity of the first covering member 2 and the metal paste layer 25 and the difference in thermal conductivity between them, the intensity of the laser, the diameter of the irradiation spot, and the moving speed of the irradiation spot can be set to cause laser ablation of the metal paste layer 25 on the first covering member 2.

[0096] The wavelength of the laser can also use a laser in the infrared region (e.g., near 1064nm), a laser in the red region (e.g., near 640nm), a laser in the green region (e.g., near 532nm), a blue region shorter than the green region, and a laser in the ultraviolet region (e.g., near 355nm). Using a wavelength in the ultraviolet region can efficiently produce ablation and improve mass productivity. In addition, the pulse width of the laser can use nanoseconds, picoseconds, femtoseconds, etc. For example, from the viewpoint of output and operating efficiency, it is preferred to use a laser with a pulse width of nanoseconds in the green region near 532nm.

[0097] It is preferred to use a laser with a narrower irradiation width than the distance between the pair of electrodes 5. For example, by setting the distance between the first electrode 5a and the second electrode 5b to 30 μm, and using an electrode with a processing width of about 30 μm by laser, the distance between the first wiring 20a and the second wiring 20b can be 30 μm. From the perspective of energy concentration, the laser is preferably irradiated to the surface of the metal paste layer 25 from a 90-degree vertical direction, but in order to effectively perform scattering based on ablation, it is preferred to irradiate from an inclined direction of 45 to 145 degrees, preferably 70 to 110 degrees, relative to the surface of the metal paste layer 25.

[0098] Laser irradiation causes the resin and metal powder of the metallic paste layer 25 to scatter, thereby collecting dust. The dust is preferably collected in a direction parallel to the surface of the light guide plate 30 or at an angle within 30 degrees relative to the surface of the light guide plate 30 .

[0099] Preferably, a first covering member 2 is disposed on the first surface of the light-emitting element 1 and between the pair of electrodes 5. In the process of forming a pair of wirings 20, the first covering member 2 disposed on the first surface of the light-emitting element 1 and between the pair of electrodes 5 is partially removed by laser. That is, the first covering member 2 disposed between the pair of electrodes 5 is not completely removed by laser, but a portion remains. Since the first covering member 2 is insulating, the short circuit between the first wiring 20a and the second wiring 20b can be prevented by leaving the first covering member 2. The thickness of the remaining first covering member 2 is preferably not less than 1 / 5 and not more than 4 / 5 of the thickness of the electrode 5.

[0100] Here, although it is a laser irradiation method, a plurality of light emitting elements 1 are arranged in row and column directions on the light guide plate 30. A metal paste layer 25 of a predetermined width is arranged on the light emitting element 1. Then, laser is irradiated between a pair of electrodes 5 of the light emitting element 1. By arranging the light emitting element 1 at a predetermined position, although the pair of electrodes 5 of the light emitting element 1 cannot be directly visually recognized, laser irradiation can be performed between the pair of electrodes 5. At this time, considering the deviation of laser irradiation, it is preferable to set the distance between the pair of electrodes 5 to be about 1.5 to 5 times wider than the spot diameter of the laser.

[0101] In addition, as a different method, it is preferable to first identify the pair of electrodes 5 of the light-emitting element 1 in the process of preparing the intermediate, and in the process of forming a pair of wirings, irradiate the laser between the pair of electrodes 5 of the light-emitting element 1 identified in the process of preparing the intermediate. By identifying the position of the pair of electrodes 5 of the light-emitting element 1 in advance in this way, it is possible to irradiate the laser to an appropriate position in consideration of the displacement of the light-emitting element 1 in the vertical direction and the rotation of the light-emitting element 1, so that the distance between the pair of electrodes 5 can be set to be narrow, and a small light-emitting element 1 can be used.

[0102] It is also possible to include a process of covering at least a pair of electrodes 5 with an insulating member 60 after the process of forming a pair of wirings. Since there is also a situation where a pair of electrodes 5 are exposed by laser ablation, it is possible to prevent short circuit by covering a pair of electrodes 5 with an insulating member 60. The insulating member 60 can not only cover a pair of electrodes 5, but also cover a pair of wirings 20, a second covering member 50, etc. In the process of covering a pair of electrodes 5 with the insulating member 60, it is preferred that the insulating member 60 is colored. The insulating member 60 can be any one of transparent, translucent, and opaque, but in order to confirm the connection state of the wiring 20, it is preferably transparent or translucent in the wavelength region of the measuring instrument or when visually observed. The measuring instrument preferably uses a spectrophotometer, for example, the spectrophotometer preferably uses blue light with a peak wavelength of 480nm, green light of 520nm, red light of 600nm, etc., but is not limited to this wavelength. In addition, the insulating member 60 is preferably colorless and transparent, but it is particularly preferably colored to the extent that it can be confirmed that the insulating member 60 is arranged on the first covering member 2, etc., or the connection state of the wiring 20 can be confirmed through the insulating member 60. For example, it is preferred that the insulating member 60 contains a coloring material, a pigment, a dye, etc. of blue, green, red, etc. The light transmittance of the insulating member 60 can be, for example, greater than 20% and less than 95%, preferably greater than 30% and less than 80%. The light transmittance of the insulating member 60 is measured using a transmittance meter. The insulating member 60 is preferably film-shaped, and the thickness W of the insulating member 60 is preferably 0.5μm to 100μm. The size of the insulating member 60 is preferably circular, elliptical, rectangular, etc. with a maximum diameter of 0.5 to 3 times the maximum diameter of the package 10.

[0103] (Package)

[0104] The package 10 comprises at least a light emitting element 1 and a first covering member 2, and may also comprise a first translucent member 3, a second translucent member 4, etc. The light emitting element 1 comprises a pair of electrodes 5 on the first surface. The first covering member 2 covers the side of the light emitting element 1, and therefore it only needs to be insulating. The first covering member 2 is preferably reflective, but may also be translucent. The reflective first covering member 2 may be, for example, a member containing about 60 wt % of silicon dioxide and white titanium oxide in a silicone resin, and may be formed by compression molding, transfer molding, injection molding, printing, spraying, etc. In addition, the first covering member may be formed into a plate shape, cut into a specified size, and formed into a rectangular parallelepiped.

[0105] A liquid second light-transmitting member 4 is applied to the first light-transmitting member 3 of the plate-like member, and a plurality of light-emitting elements 1 are bonded thereto. The liquid second light-transmitting members 4 are formed to be separated from each other. Each second light-transmitting member 4 corresponds to the shape of the light-emitting element 1 and can be set to any shape when viewed from above, for example, a square, a rectangle, a circle, an ellipse. In addition, the interval between adjacent second light-transmitting members 4 can be appropriately set according to the outer shape of the package 10 and the number of packages 10 obtained. In addition, the second light-transmitting member 4 is preferably formed to cover about 70% to 150% of the area of ​​the first light-transmitting member 3 of the plate-like member corresponding to the area of ​​the bottom surface of the package 10.

[0106] If the light-emitting element 1 is arranged on the first light-transmitting member 3 coated with the liquid second light-transmitting member 4, the second light-transmitting member 4 climbs up the side of the light-emitting element 1. As a result, when the light-emitting element 1 is placed on the first light-transmitting member 3, the outer surface of the second light-transmitting member 4 becomes a shape facing obliquely upward. For example, the second light-transmitting member 4 and the light-emitting element are combined into a quadrangular pyramid. After the light-emitting element 1 is arranged on the first light-transmitting member 3, the light-emitting element 1 can be pressed as needed. After the light-emitting element 1 is arranged, the liquid second light-transmitting member 4 is heated to form a cured second light-transmitting member 4.

[0107] In the above description, the light emitting element 1 and the first light transmissive member 3 are bonded via the second light transmissive member 4 present therebetween, but they can also be bonded directly without using the second light transmissive member 4. That is, after the light emitting element 1 is placed on the first light transmissive member 3, the first light transmissive member 4 in a liquid state can be put around the light emitting element 1.

[0108] Next, the package 10 is arranged on the light guide plate 30 via the third light-transmitting member 40 so as to contact the first light-transmitting member 3. As in the case of the second light-transmitting member 4 described above, the liquid third light-transmitting member 40 forms an outer surface obliquely upward toward the package 10, and the third light-transmitting member 40 is solidified. The second covering member 50 is provided to integrally cover a plurality of packages 10. The second covering member 50 can be formed, for example, by using a member containing about 60 wt% of silicon dioxide and white titanium oxide in a silicone resin, and can be formed by compression molding, transfer molding, injection molding, printing, spraying, etc.

[0109] Alternatively, the entire second covering member 50 may be covered so as to cover the package 10 disposed on the light guide plate 30, and after the second covering member 50 is cured, the thickness of the second covering member 50 may be reduced by a known processing method so that a pair of electrodes 5 of the light emitting element 1 are exposed. Thus, a light emitting device 100 of a predetermined thickness may be obtained. Furthermore, the surface of the pair of electrodes 5 of each package may be aligned with the surface of the second covering member 50 to be in the same plane, and the metal paste layer 25 may be easily printed.

[0110] Here, the term "plate-like" refers to a member having a large area capable of mounting one or more light-emitting elements, and may be replaced by terms such as sheet-like, film-like, or layer-like.

[0111] (Light-emitting element)

[0112] As the light emitting element 1, for example, a semiconductor light emitting element such as a light emitting diode can be used, and a light emitting element that can emit visible light such as blue, green, and red can be used. The semiconductor light emitting element includes a stacked structure including a light emitting layer and an electrode. The stacked structure includes a first surface on one side where the electrode is formed and a second surface that is a light extraction surface on the opposite side.

[0113] The stacked structure includes a semiconductor layer including a light-emitting layer. Furthermore, it may also include a light-transmitting substrate such as sapphire. As an example of a semiconductor stack, it can include three semiconductor layers: a first conductive semiconductor layer (e.g., an n-type semiconductor layer), a light-emitting layer (active layer), and a second conductive semiconductor layer (e.g., a p-type semiconductor layer). As a semiconductor layer that can emit green light or visible light from ultraviolet light or blue light, for example, it can be formed of a semiconductor material such as a III-V compound semiconductor. Specifically, Indium ions can be used. X Al Y Ga 1-X-Y A nitride-based semiconductor material such as N (0≤X, 0≤Y, X+Y≤1). As a semiconductor stack capable of emitting red light, GaAs, GaAlAs, GaP, InGaAs, InGaAsP, etc. can be used. The electrode is preferably copper.

[0114] (First covering member)

[0115] The first covering member 2 is preferably a resin member containing a thermosetting resin such as silicone resin, silicone-modified resin, epoxy resin, or phenolic resin as a main component.

[0116] The first covering member 2 is preferably a light-reflective resin member. The light-reflective resin refers to a resin material having a reflectivity of 70% or more relative to the light from the light-emitting element. For example, white resin is preferred. By reflecting the light reaching the first covering member toward the light-emitting surface of the light-emitting device, the light extraction efficiency of the light-emitting device can be improved. In addition, the first covering member 2 can also be a translucent resin member. In this case, the first covering member can use the same material as the first translucent member described later.

[0117] As the light reflective resin, for example, a resin in which a light reflective substance is dispersed in a translucent resin can be used. As the light reflective substance, for example, titanium oxide, silicon oxide, zirconium oxide, potassium titanate, aluminum oxide, aluminum nitride, boron nitride, mullite, etc. are preferred. The light reflective substance can be in the form of granules, fibers, thin plates, etc., and in particular, fibrous substances can also be expected to have an effect of reducing the thermal expansion coefficient of the first covering member, so they are preferred.

[0118] When the first covering member is composed of a resin member containing a filler such as a light-reflective substance, for example, the resin component of the surface irradiated by the laser is ablated and removed to expose the filler on the surface. In addition, by moving the irradiation spot of the laser continuously or sequentially on the surface, a stripe-shaped groove is formed in the moving direction. The groove is formed with a width of about 10 to 100 μm, typically 40 μm, and a depth of 0.1 to 3 μm, depending on the irradiation spot diameter of the laser.

[0119] (First light-transmitting member)

[0120] The first light-transmitting member 3 is disposed on the second surface of the light-emitting element. The material of the first light-transmitting member 3 can be resin, glass, etc. As the resin, a thermosetting resin such as silicone resin, silicone-modified resin, epoxy resin, phenolic resin, a thermoplastic resin such as polycarbonate resin, acrylic resin, methylpentene resin, polynorbornene resin, etc. can be used. Silicone resin having excellent light resistance and heat resistance is particularly preferred.

[0121] The first light-transmitting member 3 may contain a phosphor as a wavelength conversion material in addition to the above-mentioned light-transmitting material. The phosphor may be a phosphor that can be excited by the light emitted from the light-emitting element. For example, as a phosphor that can be excited by a blue light-emitting element or an ultraviolet light-emitting element, there can be cited yttrium aluminum garnet phosphor (YAG:Ce) activated by cerium; lutetium aluminum garnet phosphor (LAG:Ce) activated by cerium; calcium aluminosilicate phosphor (CaO-Al2O3) activated by europium and / or chromium; 2 O 3 -SiO 2 :Eu,Cr); Silicate phosphor activated by europium ((Sr,Ba) 2 SiO 4 : Eu); β-sialon phosphor, CASN phosphor, SCASN phosphor and other nitride phosphors; KSF phosphor (K 2 SiF 6 :Mn); sulfide-based phosphors, quantum dot phosphors, etc. By combining these phosphors with blue light-emitting elements or ultraviolet light-emitting elements, light-emitting devices of various colors (such as white light-emitting devices) can be manufactured.

[0122] Furthermore, the first light-transmitting member 3 may contain various fillers or the like for the purpose of adjusting viscosity or the like.

[0123] (Second light-transmitting member)

[0124] The second light-transmitting member 4 bonds the light-emitting element 1 to the first light-transmitting member 3. The second light-transmitting member may contain a fluorescent substance or a filler.

[0125] The present invention is not limited to the above-described embodiment, and any embodiment is possible without departing from the gist of the present invention.

[0126] (Third light-transmitting member)

[0127] The third light-transmitting member 40 is a light-transmitting member having adhesiveness. The third light-transmitting member 40 is preferably arranged so that the first light-transmitting member 3 of the package 10 is in contact with the light guide plate 30. The third light-transmitting member 40 preferably covers the side surface of the first light-transmitting member 3 and the side surface of the first covering member 2. This is because the light emitted from the light-emitting element 1 can be diffused laterally. The third light-transmitting member 40 can be formed of the same material as the second light-transmitting member 4.

[0128] (Light guide plate)

[0129] The light guide plate 30 may not only be a flat plate, but may also be partially concave or convex. A package may be arranged in the concave portion. In addition, the concave portion or the convex portion may have the function of a lens or the like. In addition, a depression, a shading film, a reflective film, etc. may be formed so that the light guide plate 30 has a split property. In addition, by providing a reflective film or a shading film on the opposite side of the light guide plate where the package is arranged, the light from the package can be expanded in the horizontal direction via the light guide plate.

[0130] A light emitting device according to a second embodiment will be described with reference to the drawings. Figure 5 It is a schematic perspective view of the light emitting device according to the second embodiment when viewed from the light guide plate side. Figure 6 It is a schematic cross-sectional view of a light emitting device according to a second embodiment. Figure 7 This is a schematic top view of the light-emitting device involved in the second embodiment. Here, in the process of preparing the intermediate body already described, the package 10 is arranged on the light guide plate 31 through the third light-transmitting member 40. In the accompanying drawings, the hatching used to represent the cross-sectional parts of the package and the third light-transmitting member is omitted for the sake of ease of observation of the drawings. The schematic three-dimensional view of the light-emitting device involved in the second embodiment is a segment composed of 16 units in total, namely 4 vertical units and 4 horizontal units. By combining a plurality of segments, a planar light source of any size can be formed. Schematic cross-sectional view of the light-emitting device involved in the second embodiment ( Figure 6 ) represents 1 unit.

[0131] For the light-emitting device involved in the second embodiment, a light guide plate 31 prepared in advance is used. The light guide plate 31 has a surface side where the package 10 is arranged as a plane, and a surface side opposite to the plane as a back side. The light of the package 10 is mainly released from the back side of the light guide plate 31. In one unit of the light guide plate 31, a first recess 31a is provided in the area where the package 10 is arranged. A second recess 31b is arranged between adjacent first recesses 31a in the light guide plate 31, and the second recess 31b is formed with the intersection of vertical and horizontal straight lines as the center and arranged in a grid shape. The package 10 has a light-emitting element 1 mounted on a first light-transmitting member 3, a second light-transmitting member 4 is arranged on the side of the light-emitting element 1, and a first covering member 2 is arranged to cover the second light-transmitting member 4. The first recess 31a is in the shape of a quadrangular pyramid when viewed from above, and is a trapezoidal shape with a wider opening than the bottom side when viewed in section. The opening area above the opening of the first recess 31a is larger than the bottom area. The package 10 is arranged so that the bottom of the quadrangular pyramid shape is in contact with the first light-transmitting member 3. The third light-transmitting member 40 is arranged on the side of the package 10. A reflecting member 70 is arranged in the second recess 31b of the light guide plate 31. The upper surface of the reflecting member 70 and the plane of the light guide plate 31 are covered by the second covering member 50. The reflecting member 70 and the second covering member 50 use a resin mixed with a light-reflective substance so as to efficiently reflect the light from the package 10, and the light from the package 10 is emitted from the back side of the light guide plate 31. In addition, the second recess 31b is provided with an inclination so that the light from the package 10 can be easily emitted from the back side of the light guide plate 31, preferably at an inclination angle that enables the light to be taken out from the back side of the light guide plate 31 in a vertical direction. Wiring 21 is provided on the second covering member 50. The first wiring 21a is electrically connected to the first electrode 5a of the package 10, and the second wiring 21b is electrically connected to the second electrode 5b of the package 10, and these connection parts are covered by the insulating member 60. At this time, the second recess 31b is between the adjacent first recesses 31a, that is, the joint between the units becomes the deepest. Since the reflective member 70 is arranged in the second recess 31b, the resin used in the reflective member 70 shrinks (necking) with the solidification of the resin, and a curved depression is easily generated on the upper surface of the reflective member 70 in the second recess 31b. Therefore, when printing the wiring 21, etc., it is likely that the wiring is easily broken, so in order to prevent this situation, a wide width portion 21c is provided in a part of the wiring 21. Even if the wiring 21 is not broken, when printing the wiring 21, there is a concern that white spots or wiring becomes thinner, and the resistance may increase. Therefore, it is preferable to provide the wide width portion 21c of the wiring 21 near the most depressed part of the second recess 31b and the joint between the units. The wide portion 21 c of the wiring 21 is not limited to a circular or elliptical shape, but may be a rectangular or polygonal shape. The wide portion 21 c is not limited to one, but may be provided in plurality, or may be formed in plurality of lines instead of these.When a plurality of wide portions 21 c are provided at the joints between the units, it is preferable that the plurality of wide portions 21 c are arranged in a substantially linear shape.

[0132] The back side of the light guide plate 31 is preferably provided with a third recess 31c on the opposite side of the first recess 31a. The third recess 31c is preferably, for example, conical or polygonal. This is because, by making the third recess 31c conical, etc., the light emitted from the package 10 is expanded in the horizontal direction and the inclined direction via the light guide plate 31. A light shielding member 80 may also be provided in the third recess 31c. Since the light emitted from the package 10 is emitted most strongly from directly above, uneven light emission is likely to occur when observed on the light guide plate 31. Therefore, by providing a light shielding member 80 in the third recess 31c, the light emitted from directly above the package 10 can be suppressed and uneven light emission can be reduced. The light shielding member 80 may also cover the entire third recess 31c, but preferably only a portion of the third recess 31c, for example, about 1 / 4 to 3 / 4 of the depth of the third recess 31c. The light shielding member 80 preferably covers about twice as much as the first recess 31a in a rear view of the light guide plate 31. After the light shielding member 80 is provided in the third recess 31c, the third recess 31c preferably has a truncated cone shape in a rear view.

[0133] Therefore, the light guide plate 31 includes a plurality of first recesses 31a in which the light emitting elements 1 are disposed, and second recesses 31b disposed between adjacent first recesses 31a, the second recesses 31b are provided with a reflective member 70, a second cover member 50 is provided to cover the reflective member 70, and the wiring 21 is disposed on the second cover member 50. The wiring 21 disposed on the second recess 31b preferably includes a portion, i.e., a wide portion 21c, which is wider than the wiring 21 disposed on the first recess 31a.

[0134] A light emitting device according to a third embodiment will be described with reference to the drawings. Figure 8 It is a schematic plan view of a light emitting device according to a third embodiment.

[0135] The light emitting device involved in the third embodiment adopts substantially the same method as that of the second embodiment except that the wiring involved in the second embodiment is different. The wiring 22 is provided with a wide portion 22c between the packages 10 adjacent in the lateral direction, particularly in the middle of the adjacent packages 10. The wiring 22 is provided with a curved portion near the center in the lateral direction between the adjacent packages 10, and becomes a straight line with a height difference, but the curved portion is provided at a position deviated from the middle of the adjacent packages 10. By bending the wiring 22, it is possible to suppress white spots and broken wires during printing. In addition, a wiring portion 22d with a wider line width is provided on the wiring 22 on the side different from the side where the package 10 is arranged in the lateral direction. By expanding the line width of the wiring 22, it is possible to reduce resistance or prevent broken wires. The lateral length of the wiring portion 22d is not particularly limited, but it is preferably extended to the vicinity of the wide portion 22c in the up and down directions.

[0136] Reference Fig. 9 , a light emitting device according to a fourth embodiment is described. Fig. 9 1 is a schematic cross-sectional view of a light emitting device according to a fourth embodiment. In the process of preparing the intermediate body described above, the package 10 is described as being arranged on the light guide plate 30 via the third light transmissive member 40. In addition, for the light emitting element 1 and the second light transmissive member 4, hatching for indicating cross-sectional components is omitted for ease of viewing of the drawings.

[0137] The light-emitting device according to the fourth embodiment is different from the other embodiments in that the package 10 is arranged in the through hole 30A provided in the light guide plate 30. In addition, the through hole 30A is formed in the light guide plate 30 for each package 10 provided. The package 10 includes a light-emitting element 1, a first light-transmitting member 3 provided on the light-emitting element 1 via a second light-transmitting member 4, a first light-reflecting film 13 provided on the first light-transmitting member 3, and a first covering member 2 provided on the side surface of the light-emitting element 1 via the second light-transmitting member 4. Moreover, the package 10 is provided on the light guide plate 30 via a third light-transmitting member 40. In addition, it is preferred that the side of the package 10 arranged on the light guide plate 30 is covered with a second covering member 50. The thickness of the second covering member 50 is preferably thinner than the thickness of the package 10, but may be the same or thicker. In addition, in order to install the package 10 , the package 10 may be installed via a work sheet that blocks one hole opening of the through hole 30A formed in the light guide plate 30 .

[0138] Moreover, the first light reflecting film 13 of the first light-transmitting member 3 provided in the package 10 is formed, as an example, to be flush with the surface of the light guide plate 30. The first light reflecting film 13 reflects or blocks light. The first light reflecting film 13 is preferably formed of a material that blocks or reflects 80% or more of the light sent from the first light-transmitting member 3. As the first light reflecting film 13, a single-layer film composed of a metal, a multi-layer film composed of a metal, or a multi-layer film composed of a dielectric in which two or more dielectrics are stacked (a dielectric multi-layer film) can be used. As an example, the first light reflecting film 13 can be formed by a sputtering method. The first light reflecting film 13 may also have the same area as the first light-transmitting member 3 when viewed from above, or an area larger than the first light-transmitting member 3. This is because by increasing the size of the first light-transmitting member 3, light from the light-emitting element 1 that is directed directly upward can be guided to the side. When the first light reflecting film 13 is formed to have a larger area than the first light transmissive member 3 , it is preferable to use a plate-shaped first light reflecting film 13 .

[0139] In addition, when the first light reflecting film 13 is formed in advance and connected with an adhesive material, adhesives such as acrylic, urethane, styrene, epoxy, polyimide, silicone, BT resin, ester, ether, urea, polyamide, phenol, and cellulose derivatives can be used in the form of a monomer or in combination.

[0140] Furthermore, when a dielectric multilayer film is used, for example, a DBR (distributed Braggreflector) film can be used. As the first light reflecting film 13, a film including a dielectric multilayer film is preferably used. If it is a dielectric multilayer film, the absorption of light from the light-transmitting sheet is less compared to a reflective film formed by a metal or the like, and light can be effectively reflected. When both a metal film and a dielectric multilayer film are used as the first light reflecting film 13, it is preferred to sequentially configure the dielectric multilayer film and the metal film starting from the set surface. In addition, when a metal film is used for the first light reflecting film 13, a monomer or alloy such as aluminum or silver can be used.

[0141] In addition, in the light emitting device, other structures are equivalent to the structures already described.

[0142] In the light emitting device described in each embodiment, the structure of the first light transmissive member 3 of the package 10 may be Fig. 10A as well as Fig. 10B The method shown. Fig. 10A as well as Fig. 10B Schematic diagrams schematically showing modified examples of the packages of the respective embodiments. In the drawings, hatching for indicating cross-sectional components of the light emitting element is omitted for ease of viewing.

[0143] In the package 10A, the first light-transmitting member 3A is formed to cover the side and second surface of the light-emitting element 1. The first light-transmitting member 3A is made of the same material as the member already described. The first light-transmitting member 3A is formed to cover the upper surface (lower surface in the figure), that is, the second surface and the side surface of the light-emitting element 1, so that light can be easily transmitted from the light-emitting element 1 to a farther part of the light guide plate 30. In addition, in the package 10B, a second light-reflecting film 14 can also be formed on the lower surface of the first light-transmitting member 3A provided on the side and second surface of the light-emitting element 1 and the lower surface of the light-emitting element 1, so that the element electrode 5 of the light-emitting element 1 is exposed. The second light-reflecting film 14 can be formed using a white resin that performs diffuse reflection and a member equivalent to the second covering member already described. In the package 10B, by providing the second light-reflecting film 14, the extraction efficiency of the light from the light-emitting element 1 irradiated from the light guide plate 2 side can be further improved.

[0144] In addition, Fig. 10A as well as Fig. 10B When any of the packages 10A and 10B shown is installed on the light guide plate 30 and used, it is used in a state where the first light reflecting film 13 is provided on the upper surface of the first light transmissive member 3A.

[0145] Next, refer to Fig.11 , the light-emitting device involved in the fifth embodiment is described. Fig.11 1 is a schematic cross-sectional view of a light emitting device according to the fifth embodiment. In the process of preparing the intermediate body described above, the package 10 is arranged on the light guide plate 31 via the third light-transmitting member. In the drawings, the hatching lines for indicating the cross-sectional parts of the package and the third light-transmitting member are omitted for the sake of easy viewing of the drawings. In the light emitting device according to the fifth embodiment, the first auxiliary wiring 21a1 is formed on the first wiring 21a, and the second auxiliary wiring 21b1 is formed on the second wiring 21b. Figure 6 That is, in the light emitting device according to the fifth embodiment, the resin material of one or both of the reflective member 70 and the second covering member 50 filled in the second recess 31b formed in the light guide plate 31 may shrink (neck) during curing to generate a curved depression on the upper surface. Therefore, by providing the first auxiliary wiring 21a1 on the first wiring 21a and providing the second auxiliary wiring 21b1 on the second wiring 21b, the flatness is maintained.

[0146] In addition, since the curved depression is formed on the upper surface of the second cover member 50, there is a concern that the first wiring 21a and the second wiring 21b become narrower or thinner, and the resistance becomes higher. Therefore, by providing the first auxiliary wiring 21a1 in the first wiring 21a and the second auxiliary wiring 21b1 in the second wiring 21b, the resistance can be reduced or disconnection can be prevented.

[0147] The first auxiliary wiring 21a1 used here is formed by overlapping the material with the same width and thickness as the first wiring 21a, so that the depression of the resin material is nearly flat. In addition, the second auxiliary wiring 21b1 is also formed by overlapping the material with the same width and thickness as the second wiring 21b, similarly to the first auxiliary wiring 21a1, so that the depression of the resin material is nearly flat. In addition, the first auxiliary wiring 21a1 and the second auxiliary wiring 21b1 are formed into a plurality of layers of two or more layers so that flatness can be maintained.

[0148] In addition, the first auxiliary wiring 21a1 and the second auxiliary wiring 21b1 may be formed to have a wiring width wider than the first wiring 21a and the second wiring 21b. Furthermore, the first auxiliary wiring 21a1 is formed to have a length of more than 50% of the length of the first wiring 21a, and is formed within a range that allows the recessed portion to be flat. The length of the second auxiliary wiring 21b1 is also formed to have a length of more than 50% of the length of the second wiring 21b. In addition, the first auxiliary wiring 21a1 and the second auxiliary wiring 21b1 may be formed to have the same length or different lengths.

[0149] The first auxiliary wiring 21a1 and the second auxiliary wiring 21b1 can be formed by printing, etc., similarly to the first wiring 21a and the second wiring 21b. Therefore, it is preferred that the first auxiliary wiring 21a1 and the second auxiliary wiring 21b1 are provided on the first wiring 21a and the second wiring 21b so that the first auxiliary wiring 21a1 and the second auxiliary wiring 21b1 are provided near the most depressed part or at the joint between the units.

[0150] Next, refer to Fig.12 , the light-emitting device involved in the sixth embodiment is described. Fig.121 is a schematic cross-sectional view of a light emitting device according to a sixth embodiment. Here, in the process of preparing the intermediate body described above, the package 10 is described as being arranged on the light guide plate 31 via the third light-transmitting member 40. In the drawings, hatching lines for indicating cross-sectional parts are omitted for the sake of ease of viewing of the drawings. In the light emitting device 100D according to the sixth embodiment, a second covering member 50 is formed on the second recess 31b of the light guide plate 31, and a third light reflecting film 15 is formed on the surface of the light guide plate 31 on the opposite side of the light emitting side thereof along the shape of the second recess 31b formed on the light guide plate 31. Figure 6 The light emitting device involved in the second embodiment is different.

[0151] The third light reflecting film 15 is provided to cover one side surface of the light guide plate 31 in addition to the first recess 31a. The third light reflecting film 15 is preferably formed of a material that blocks or reflects light by 80% or more. As the third light reflecting film 15, a single layer composed of metal, a multilayer film composed of metal, or a multilayer film composed of a dielectric in which two or more dielectrics are stacked (a dielectric multilayer film) can be used. In addition, as an example, the third light reflecting film 15 can be formed by a sputtering method. The third light reflecting film 15 can use the same material and the same formation method as the first light reflecting film already described.

[0152] The light emitting device 100D is formed by filling the second recess 31b of the light guide plate 31 with the second covering member 50. The light emitting device 100D may be electrically connected to the electrode 5 of the light emitting element 1 via the connection substrate 90.

[0153] The wiring substrate 90 includes a wiring layer 91 on a base material, and includes a cover layer 92 made of an insulating material to protect the wiring layer 91. The wiring substrate 90 includes a flat support member and the wiring layer 91 disposed on the surface and / or inside of the support member. In addition, the wiring substrate 90 is set to set the shape, size, and other structures of the electrodes according to the number of light-emitting elements 1 and the structure and size of the element electrodes.

[0154] The supporting member of the wiring substrate 90 is preferably made of an insulating material, and is preferably made of a material that is difficult to transmit light emitted from the light emitting element 1, external light, etc. The wiring substrate 90 may also be a material having a certain degree of strength, a material used as a sheet material, or a flexible substrate. Specifically, ceramics such as alumina, aluminum nitride, and mullite, phenolic resin, epoxy resin, polyimide resin, BT resin (bismaleimide-triazine resin), polyphthalamide (PPA), and the like may be cited.

[0155] The wiring layer 91 includes a first wiring 91a electrically connected to the first electrode 5a of the package 10, and a second wiring 91b electrically connected to the second electrode 5b of the package 10. Although the positions of the first wiring 91a and the second wiring 91b are different, they are different from those already described, and the materials, etc. are unchanged. In addition, the wiring layer 91 is covered by the cover layer 92 except for the position of the electrode 5.

[0156] The covering layer 92 protects the wiring layer 91. The covering layer 92 is provided so as to form an opening 92a at the position of the electrode 5 of the package 10 and to cover the wiring layer 91. The covering layer 92 is formed of, for example, an insulating member using polyimide as a base material. Moreover, the covering layer 92 is formed so as to cover the wiring layer 91 by, for example, screen printing or the like, and is formed so as to be provided with an opening 92a at the position of the electrode 5 via a mask.

[0157] The wiring layer 91 of the wiring substrate 90 is formed so as not to cause a short circuit in the above-described step of forming a pair of wirings before being electrically connected to the first electrode 5 a and the second electrode 5 b of the package 10 .

[0158] Since the light emitting device 100D has the above-described structure, it can be used without reducing the irradiation efficiency of light from the light guide plate 31 due to the third light reflecting film 15 .

[0159] Next, refer to Fig.13 , the light-emitting device involved in the 7th embodiment is described. Fig.13 1 is a schematic cross-sectional view of a light emitting device according to the seventh embodiment. In addition, the same reference numerals are given to the structures already described and the description thereof is omitted. In addition, in the process of preparing the intermediate body already described, the package 10 is described as being arranged on the light guide plate 31 via the third light-transmitting member 40. Furthermore, the first wiring 21a and the second wiring 21b are formed by a process of forming a pair of wirings by irradiating a wiring portion formed by a metal paste layer with a laser to remove a portion of the metal paste layer.

[0160] The light emitting device 100E according to the seventh embodiment is different in that the insulating member 60 is provided in two layers in order to flatten the recess generated in the second covering member 50 .

[0161] That is, the light-emitting device 100E comprises: a light guide plate 31; a second covering member 50, which fills the second recess 31b of the light guide plate 31; a package 10, which has a light-emitting element 1 arranged in the first recess 31a of the light guide plate 31; a first wiring 21a and a second wiring 21b, which are respectively connected to the electrode 5 of the light-emitting element 1 and formed on the second covering member 50; an insulating film 60a of the insulating member 60, which is arranged to cover the first wiring 21a and the second wiring 21b and open the external connection portion; and an auxiliary insulating film 60b of the insulating member 60, which is arranged to correspond to the recessed portion formed by shrinkage when the second covering member 50 is cured.

[0162] In this way, in the light emitting device 100E, by covering the recessed portion of the second covering member 50, the insulating film 60a and the auxiliary insulating film 60b form two layers, and the flatness can be ensured. Therefore, in the light emitting device 100E, the coating accuracy of each component is improved, and the working speed is more efficient (for example, UPH: unit per hour). The auxiliary insulating film 60b is not limited to one layer, and can be set to two or more layers. In addition, the insulating film 60a only needs to cover at least a part of the second covering member 50 and the pair of wirings 21. For example, the insulating film 60a is formed in a state where the portion for electrically connecting the pair of wirings 21 is opened.

[0163] In the first to seventh embodiments, in terms of the relationship between the drawings, the diagrams showing the components where the second cover member 50 is formed and the diagrams showing the components where the second cover member 50 and the reflective member 70 are formed are mixed. However, in each embodiment, of course, any structure in which the second cover member 50 is formed on the light guide plates 30 and 31 or the second cover member 50 and the reflective member 70 are provided on the light guide plates 30 and 31 may be used.

[0164] In addition, in each embodiment, the wide width portions 21 c and 22 c and the insulating film 60 a and / or the auxiliary insulating film 60 b may be provided.

Claims

1. A light emitting device, comprising: A package comprising a light emitting element, a first light transmissive member, a pair of electrodes, and a first covering member, wherein the light emitting element has a first surface and a second surface opposite to the first surface, the first light transmissive member is arranged on the second surface side of the light emitting element, the pair of electrodes are arranged on the first surface side of the light emitting element, and the first covering member covers the light emitting element so that the pair of electrodes are exposed; a light guide plate, on which the packaging component is arranged; a second covering member, covering the light guide plate and covering the side of the package; and a pair of wirings continuously covering the exposed pair of electrodes and the first covering member and connected to the pair of electrodes respectively; The pair of wirings are a mixture of resin and metal powder and have conductivity, The pair of electrodes has an irradiation spot of the laser light between them.

2. The light emitting device according to claim 1, wherein: The package further includes a second light-transmitting member disposed on a side surface of the light-emitting element.

3. The light emitting device according to claim 2, wherein: The second light-transmitting member is disposed between the second surface of the light-emitting element and the first light-transmitting member. The second light-transmitting member bonds the second surface of the light-emitting element to the first light-transmitting member.

4. The light emitting device according to claim 2 or 3, wherein: The light emitting element is placed on the first light transmissive member, and an outer surface of the second light transmissive member extends obliquely upward toward the package.

5. The light emitting device according to any one of claims 1 to 4, wherein: The light guide plate has a first recess or a through hole, The package or the light emitting element is arranged in the first recess or the through hole, A third light-transmitting member for bonding the package or the light-emitting element to the light guide plate is disposed in the first recess or the through hole.

6. The light emitting device according to any one of claims 1 to 5, wherein: At least one groove located between the pair of electrodes has a width of 10 μm to 100 μm, and a depth of 1 μm to 3 μm.

7. The light emitting device according to claim 5 or 6, wherein: The depth of the first recess is the same as or smaller than the height of the package.

8. The light emitting device according to any one of claims 1 to 7, wherein: The thickness of the pair of wirings is greater than or equal to 1 μm and less than or equal to 50 μm.

9. The light emitting device according to any one of claims 5 to 8, wherein: The third light-transmitting member has an outer surface extending obliquely upward toward the package.

10. The light emitting device according to any one of claims 1 to 9, wherein: The size of the metal powder is not less than 0.01 μm and not more than 10 μm.

11. The light emitting device according to any one of claims 1 to 10, wherein: The concentration of the metal powder contained in the pair of wirings is 60 wt % or more and 95 wt % or less.

12. The light emitting device according to any one of claims 1 to 11, wherein: The light guide plate further has a second recess, The second recessed portion is located between the adjacent first recessed portions, and the second recessed portion has a lattice shape centered at the intersection of the vertical and horizontal straight lines.

13. The light emitting device according to claim 12, wherein: The pair of wirings has a wide portion having a width wider than the remaining portion, The wide portion is provided in the second recessed portion.

14. The light emitting device according to any one of claims 1 to 13, wherein: The light guide plate is further provided with a third recess on the opposite side of the first recess. A light shielding member is provided in the third recessed portion.

15. The light emitting device according to any one of claims 1 to 14, wherein: The pair of electrodes is further covered with a colored insulating member.

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