JP2021052117A - Light-emitting device and manufacturing method for the same - Google Patents

Abstract

To provide a manufacturing method for a compact light-emitting device with high reliability.SOLUTION: A manufacturing method for a light-emitting device includes the steps of: preparing an intermediate body including a light-emitting element including a pair of electrodes on a first surface side and a first covering member that covers the light-emitting elements so that a part of surfaces of the pair of electrodes is exposed; forming a conductive layer 25 that covers continuously the exposed pair of electrodes and the first covering member; and forming a pair of wires so as to avoid the short-circuiting between the pair of electrodes by irradiating the conductive layer on the pair of electrodes and the conductive layer on the first covering member with laser light and removing a part of the conductive layer between the pair of electrodes and the conductive layer on the first covering member. The conductive layer used in the step of forming the conductive layer is the conductive layer containing resin or solvent in a plurality of carbon particles, or containing only carbon particles.SELECTED DRAWING: Figure 2C

Description

The present invention relates to a light emitting device and a method for manufacturing the same.

Instead of providing a housing for accommodating the light emitting element, a sealing member containing a reflective material covers the side surface and the lower surface of the light emitting element, and a plated electrode in contact with the lower surface of the bump electrode of the light emitting element and the lower surface of the sealing member is provided. A small light emitting device is known (for example, Patent Document 1).

Further, there is known a method for manufacturing a light emitting device that forms a metal layer that continuously covers a pair of electrodes and a covering member and irradiates a laser beam to remove a part of the metal layer (for example, Patent Document 2). ).

Japanese Unexamined Patent Publication No. 2012-124443 Japanese Unexamined Patent Publication No. 2017-118098

The present embodiment provides a method for manufacturing a highly reliable light emitting device while being a small light emitting device.

In the method for manufacturing a light emitting device according to an embodiment of the present invention, a light emitting element having a pair of electrodes on the first surface side and a first light emitting element covering the light emitting element so that a part of the surface of the pair of electrodes is exposed. A step of preparing an intermediate body including the covering member, a step of forming a conductive layer that continuously covers the pair of exposed electrodes and the first covering member, and the step of forming the conductive layer on the pair of electrodes. The conductive layer and the conductive layer on the first coating member are irradiated with laser light to remove a part of the conductive layer between the pair of electrodes and the conductive layer on the first coating member, and the pair is removed. The conductive layer used in the step of forming the conductive layer includes a step of forming a pair of wires so as not to short-circuit the electrodes of the above, and the conductive layer contains a resin or a solvent in a plurality of carbon particles. Or, only carbon particles.

The light emitting device according to the embodiment of the present invention includes a light emitting element provided with a pair of electrodes on the first surface side, and a first covering member covering the light emitting element so that a part of the surface of the pair of electrodes is exposed. The pair of exposed electrodes and the first covering member are continuously covered, and the pair of electrodes have a pair of wirings that are not electrically connected to each other, and the pair of electrodes on the light emitting element. The wiring is one in which a resin is contained in a plurality of carbon particles, or only carbon particles.

As described above, it is possible to provide a highly reliable manufacturing method of a light emitting device while being a small light emitting device.

It is the schematic perspective view from the upper oblique side of the package which concerns on embodiment. It is a schematic bottom view of the package which concerns on embodiment. It is the schematic sectional drawing of the package which concerns on embodiment. It is schematic cross-sectional view explaining the manufacturing method of the light emitting device which concerns on embodiment. It is schematic cross-sectional view explaining the manufacturing method of the light emitting device which concerns on embodiment. It is schematic cross-sectional view explaining the manufacturing method of the light emitting device which concerns on embodiment. It is schematic cross-sectional view explaining the manufacturing method of the light emitting device which concerns on embodiment. It is schematic cross-sectional view explaining the manufacturing method of the light emitting device which concerns on embodiment. It is a schematic bottom view explaining the manufacturing method of the light emitting device which concerns on embodiment. It is a schematic bottom view explaining the manufacturing method of the light emitting device which concerns on embodiment. It is a schematic bottom view explaining the manufacturing method of the light emitting device which concerns on embodiment. It is a schematic bottom view explaining the manufacturing method of the light emitting device which concerns on embodiment. It is the schematic plan view of the light emitting device which concerns on embodiment. It is the schematic perspective view of the light emitting device which concerns on embodiment. It is the schematic perspective view from the light guide plate side of the light emitting device which concerns on 2nd Embodiment. It is the schematic sectional drawing of the light emitting device which concerns on 2nd Embodiment. It is the schematic plan view of the light emitting device which concerns on 2nd Embodiment. It is the schematic plan view of the light emitting device which concerns on 3rd Embodiment. It is a cross-sectional photograph of Test Example 1. It is a cross-sectional photograph of Test Example 2. It is a cross-sectional photograph of Test Example 3. It is a cross-sectional photograph of Reference Example 1.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following description, terms indicating a specific direction or position (for example, "top", "bottom", "right", "left", and other terms including those terms) are used as necessary. .. The use of these terms is to facilitate understanding of the invention with reference to the drawings, and the meaning of these terms does not limit the technical scope of the invention. Further, the parts having the same reference numerals appearing in a plurality of drawings indicate the same parts or members. Further, the resin members such as the first translucent member, the second translucent member, and the covering member will be described by using the same names regardless of before and after molding, solidification, curing, and individualization. That is, a member whose state changes depending on the stage of a process, such as a case where it is liquid before molding, becomes a solid after molding, and further becomes a solid whose shape is changed by dividing the solid after molding, is described by the same name. To do.

Package 10 according to the embodiment is shown in FIGS. 1A to 1C. FIG. 1A is a schematic perspective view of the package according to the embodiment from the upper oblique direction. FIG. 1B is a schematic bottom view of the package according to the embodiment. FIG. 1C is a schematic cross-sectional view of the package according to the embodiment, and is a cross-sectional view taken along the line IC of FIG. 1A. Although the package 10 will be described as an example of the intermediate, various forms may be adopted as long as the light emitting element 1 and the first covering member 2 are provided.

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. Although the package 10 is a rectangular parallelepiped, it may have any shape. Although the light emitting element 1 is rectangular in a plan view, it 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 part 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 first surface side is intended to include not only the case where the electrode is directly formed on the light emitting element 1 but also the case where the electrode is indirectly formed via another member such as a semiconductor layer or a metal. The pair of electrodes 5 has a first electrode 5a and a second electrode 5b having 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. In a plan view, the size of the first translucent member 3 may be larger, the same size, or smaller than the second surface of the light emitting element 1. When the size of the first translucent member 3 is the same as the second surface of the light emitting element 1 or larger than the second surface, even if the second translucent member 4 is arranged on the side surface of the light emitting element 1. Good. Further, the second translucent member 4 may be arranged between the light emitting element 1 and the first translucent member 3. Although the first translucent member 3 is rectangular in a plan view, it may be a polygon such as a triangle, a pentagon, or a hexagon. The second translucent member 4 preferably plays a role of adhering the light emitting element 1 and the first translucent member 3. The first covering member 2 is provided so as to cover the first surface and side surface of the light emitting element 1, the first translucent member 3, and the second translucent member 4 so that the surfaces of the pair of electrodes 5 are exposed. The first covering member 2 can be formed in one step, but can be formed in a plurality of steps of two or more times. When the first covering member 2 is formed by two or more steps, a plurality of layers may be used, or one layer may be formed without an interface.

Using the above package, a light emitting device can be formed by the following steps. 2A to 2E are schematic cross-sectional views illustrating a method of manufacturing the light emitting device according to the embodiment. Two packages are shown as an example, but the present invention is not limited to this, and a plurality of packages can be used. 3A to 3D are schematic bottom views illustrating a method of manufacturing the light emitting device according to the embodiment. FIG. 4A is a schematic plan view of the light emitting device according to the embodiment. FIG. 4B is a schematic perspective view of the light emitting device according to the embodiment. FIG. 4A shows a state before the light emitting device is fragmented, and FIG. 4B shows the fragmented light emitting device.

A method for manufacturing a light emitting device according to an embodiment includes a light emitting element provided with a pair of electrodes on the first surface side, and a first coating member covering the light emitting element so that a part of the surface of the pair of electrodes is exposed. A step of preparing an intermediate body comprising the above, a step of forming a conductive layer that continuously covers the pair of exposed electrodes and the first coating member, and the conductive layer and the conductive layer on the pair of electrodes. The conductive layer on the first coating member is irradiated with laser light to remove a part of the conductive layer between the pair of electrodes and the conductive layer on the first coating member, and the pair of electrodes are formed. The conductive layer used in the step of forming the conductive layer, which includes a step of forming a pair of wires so as not to cause a short circuit, includes a resin or a solvent contained in a plurality of carbon particles, or carbon. Only particles.

By irradiating the conductive layer with laser light, laser ablation is generated and a part of the conductive layer on the intermediate is removed. As a result, the conductive layer is patterned, and the conductive layer can be used as a wiring or an external connection electrode. Laser ablation is a phenomenon in which the surface of a solid is removed when the irradiation intensity of the laser light applied to the surface of the solid exceeds a certain magnitude (threshold value). By using laser ablation, the conductive layer can be patterned without using a mask or the like.

For example, when a metal layer is used to form wiring, the work process such as sputtering and vapor deposition is complicated and advanced equipment is required to form the metal layer, which is costly. Further, if the metal layer is a thin film, disconnection is likely to occur, so that the metal layer is required to be thick. On the other hand, when laser ablation is generated by irradiating a metal layer with laser light so as not to cause a short circuit to form dissimilar electrodes, if the metal layer is thick, the laser output must be increased, or the metal layer may melt out. It takes time and effort to remove the laser output, and the laser output becomes high and the first covering member arranged between the pair of electrodes is removed too much. Therefore, adjustment of the laser output and improvement of work efficiency are required.

On the other hand, by using the conductive layer in the embodiment, wiring can be formed easily and with high accuracy. Further, since the conductive layer contains resin or solvent in a plurality of carbon particles or is only carbon particles, the resin or carbon easily flies by irradiating the conductive layer with laser light, and the laser output is significantly suppressed. be able to. In addition, the laser irradiation time can be significantly shortened, and the work efficiency can be significantly improved. In addition, since the work efficiency can be significantly improved by laser ablation, the conductive layer can be made thicker and disconnection can be less likely to occur. Further, by removing a part of the conductive layer by using laser ablation, a groove having a narrow line width can be formed, and a smaller light emitting device can be realized with high reliability.

A plurality of packages are arranged on the light guide plate, but the number thereof is not particularly limited. For example, after arranging a large number of packages on the light guide plate, a total of 16 packages of 4 rows and 4 columns are separated into one segment. By electrically connecting this one segment, it is possible to make a large display that can be expanded, and even if a part of the display is out of light, it can be replaced for each segment, so that it can be easily replaced.

Hereinafter, each step will be described in detail.

(Process to prepare intermediate)
An intermediate including a light emitting element 1 having a pair of electrodes 5 on the first surface side and a first covering member 2 covering the light emitting element 1 so that a part of the surface of the pair of electrodes 5 is exposed is prepared. To do.

The package 10 is placed on the light guide plate 30. The package 10 is preferably arranged on the light guide plate 30 via a third translucent member 40 having adhesiveness. It is preferable that the first translucent member 3 of the package 10 and the light guide plate 30 are arranged so as to be in contact with each other. The third translucent member 40 preferably covers the side surface of the first translucent 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 spread laterally. A plurality of packages 10 are arranged on the light guide plate 30, and it is preferable that the packages 10 are arranged in a state of being regularly arranged in the vertical direction and the horizontal direction. It is preferable that the side of the package 10 arranged on the light guide plate 30 is 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 may be the same or thicker. This is to facilitate the formation of the conductive layer 25 or the wiring 20. The pair of electrodes 5 preferably contains Cu. This is because the conductivity is good.

The light guide plate 30 may be a flat plate, or a recess for arranging the package 10 may be provided in a part of the flat plate. The concave portion is rectangular in a plan view and is preferably similar to the package 10, but may be a polygon such as a triangle, a pentagon, a hexagon, or a circle. The depth of the recess may be the same as the height of the package 10 or may be shallow. By making the depth of the recess shallower than the height of the package 10, the package 10 may partially protrude from the light guide plate 30 in a cross-sectional view, and the side surface of the package 10 may be covered with the second covering member 50.

The distance between the adjacent light emitting elements 1 can be appropriately selected depending on the size of the target light emitting device 100, the size of the light emitting element 1, and the like. However, since the covering member is cut into individual pieces in a later process, the width of the cut portion (width of the cutting blade) and the like are also taken into consideration when arranging.

The first covering member 2 is arranged on the first surface of the light emitting element 1 and between the pair of electrodes 5. The distance between the pair of electrodes 5 is preferably 10 μm or more, and particularly preferably 20 μm or more. The distance between the pair of electrodes 5 is preferably 100 μm or less, and particularly preferably 50 μm or less. As a result, it is possible to easily form a pair of wirings by irradiating the laser beam described later, and a small package 10 can be used. It is preferable to set the distance between the electrodes 5 according to the pulse width of the laser beam, and it is preferable that the width is narrow as long as it does not cause a short circuit.

(Step of forming a conductive layer)
A conductive layer 25 is formed that continuously covers the pair of exposed electrodes 5 and the first covering member 2. The conductive layer 25 may at least cover the light emitting element 1 or the package 10. It is preferable to arrange a metal paste layer or a metal layer between the plurality of packages 10 instead of a conductive layer containing carbon particles.

A plurality of packages 10 are arranged on the light guide plate 30, each package 10 is arranged via a third translucent member 40, and a second covering member 50 is arranged on the side of the package 10. The conductive layer 25 is arranged so that the first covering member 2 and the second covering member 50 are continuous. The step of forming the conductive layer 25 is preferably formed by either printing or spraying. For printing, any method such as gravure printing, letterpress printing, lithographic printing, and screen printing can be used, and screen printing is preferable. For spraying, any method of inkjet, air dispense, or jet dispense can be used. As a result, the conductive layer 25 and the wiring 20 can be easily formed without requiring advanced equipment such as sputtering and vapor deposition. The thickness of the conductive layer 25 is preferably 5 μm or more, preferably 10 μm or more, and particularly preferably 12 μm or more, 15 μm or more, and 20 μm or more. 50 μm or less is preferable, and 35 μm or less and 30 μm or less are particularly preferable. In particular, it is preferably formed to be 20 μm or more, and particularly preferably 25 μm or more and 30 μm or less. By making the thickness equal to or more than a predetermined thickness, continuity can be ensured and reliability can be improved. Further, the electric resistance can be lowered by making the conductive layer 25 a predetermined thickness. Even when the conductive layer 25 has a predetermined thickness in this way, the wiring 20 can be easily formed by using laser ablation. The width of the conductive layer 25 may be conductive, and is preferably 200 μm or more and 1000 μm or less, and particularly preferably 400 μm or more and 700 μm or less.

In the step of preparing the intermediate, a plurality of light emitting elements 1 are used, in the step of forming the conductive layer 25, each of the plurality of light emitting elements 1 is continuously covered, and in the step of forming the wiring 20 described later, a plurality of light emitting elements are emitted. It is preferable that the element 1 is electrically connected. As a result, a plurality of light emitting elements 1 can be easily wired. That is, since the conductive layer 25 functions as wiring, it is used for electrically connecting a plurality of light emitting elements to each other or electrically connecting an external electrode and a light emitting element.

The conductive layer 25 used here preferably contains a resin in a plurality of carbon particles, and may further contain an organic solvent. The carbon particles preferably have a maximum diameter of 0.01 μm or more and 10 μm or less, and particularly preferably 0.1 μm or more and 5 μm or less. Examples of the carbon particles used include commercially available acetylene black, ketjen black, carbon graphite and carbon fiber or crushed products thereof, graphene and carbon nanotubes. The particles may be agglomerated. The conductivity can be improved by controlling the size of the carbon particles used in the conductive layer 25. Further, the viscosity can be adjusted when the conductive layer 25 is printed. The carbon particles preferably contain at least 50% by volume or more of either a flat shape or a needle shape. This is because the contact area between the carbon particles can be increased, the conductivity can be increased, and the electric resistance can be suppressed to be low. Before curing the conductive layer 25, the resin may be either powdery or liquid, but it is preferable that the resin is liquid from the viewpoint of workability. The carbon particles may be coated with a white conductive member. As a result, the light reflectance of the conductive layer 25 and the wiring 20 can be increased. Since carbon particles have a significantly smaller specific gravity than metal particles such as copper particles and silver particles, they are expressed in% by volume for convenience of clarifying the difference.

The conductive layer 25 may contain at least 50% by volume, preferably 20% by volume or less, of metal powder, for example, silver powder, copper powder, or silver powder or copper powder covered with a metal film. As a result, the electric resistance value can be lowered and the conductivity can be increased.

The conductive layer 25 preferably has a carbon particle concentration of 50% by volume or more and 100% by volume or less. By increasing the concentration of carbon particles, a thick film can be formed and the connection reliability with the light emitting element can be improved. Further, by setting the ratio of the resin in a predetermined range, printing or the like can be facilitated.

When the conductive layer 25 contains a solvent in a plurality of carbon particles, it is preferable to have a step of removing the solvent after the step of forming the conductive layer 25 and before the step of forming the wiring 20. This is because the wiring 20 containing only carbon particles can be formed by removing the solvent. The solvent can be easily removed by heating the conductive layer 25 to a predetermined temperature. The temperature at which the solvent is removed may be heated to the boiling point of the solvent, but the solvent may be removed by allowing the solvent to stand for a predetermined time even if it is below the boiling point of the solvent due to the vapor pressure.

In the step of forming the conductive layer 25, the conductive layer 5 is formed separately on the plurality of light emitting elements 1. Before or after the step of forming the pair of wirings described later, at least two or more conductive layers 25 are electrically connected by a metal paste layer containing metal particles in the resin or a metal layer formed only of metal. It is preferable to form a pair of wires 20. It is assumed that only the conductive layer of the portion of the light emitting element 1 to be irradiated with the laser beam contains carbon particles, and the wiring connecting the plurality of light emitting elements or the light emitting element and the external electrode is not irradiated with the laser light, so a metal paste is used. The wiring can be formed of layers or metal layers. The metal paste layer or the metal layer is arranged on a predetermined light guide plate except on the light emitting element before the step of forming the conductive layer, and then the conductive layer is formed on the light emitting element to establish an electrical connection. Can be a pair of wires. Further, after forming the conductive layer, a metal paste layer or a metal layer may be arranged on a predetermined light guide plate for wiring so as to electrically connect at least two conductive layers. The conductive layer containing carbon particles and a part of the metal paste layer or the metal layer are arranged so as to overlap each other. The conductive layer containing carbon particles provided on the light emitting element is preferably only the upper part of the package 10, but the conductive layer containing carbon particles may be provided within twice the size of the package 10 including the upper part of the package 10.

(Process of forming a pair of wiring)
The conductive layer 25 on the pair of electrodes 5 and the conductive layer 25 on the first coating member 2 are irradiated with laser light, and one of the conductive layer 25 between the pair of electrodes 5 and the conductive layer 25 on the first coating member 2 The portion is removed, and a pair of wirings 20 are formed so that the pair of electrodes 5 are not short-circuited. The wiring 20 is formed by cutting a part of the conductive layer 25, and does not use a material different from that of the conductive layer 25. Further, by irradiating the laser beam to remove a part of the conductive layer 25, the conductive layer 25 is divided between the pair of electrodes 5 of one light emitting element 1, and the pair of wirings 20 is formed. It is in a state of being continuous with the conductive layer 25 covering the electrodes of the plurality of adjacent light emitting elements 1. That is, if the conductive layer 25 between the electrodes 5 of one light emitting element 1 is divided and the conductive layer 25 between the electrodes 5 of the other light emitting element 1 remains, it does not function as wiring.

The conductive layer 25 is printed or sprayed to cure the resin contained in the conductive layer 25. For curing, a curing method such as heating or laser irradiation can be used. The cured conductive layer 25 is irradiated with laser light. The laser beam is preferably pulsed, and the size of one pass is adjusted as appropriate. The number of pulse irradiations is preferably 1 to 10 times or less, and particularly preferably 2 to 5 times or less. By increasing the thickness of the conductive layer 25, the conductivity can be increased and the electrical resistance can be decreased. On the other hand, the conductive layer 25 is cut so that the first electrode 5a and the second electrode 5b are not short-circuited. The number of times will increase. Since the process time for forming the pair of wirings 20 becomes longer as the number of times of pulse irradiation increases, it is preferable that the number of times of pulse irradiation is small. Therefore, it is preferable that the number of pulse irradiations is 2 to 5 times or less. Further, the same place may be continuously pulse-irradiated a plurality of times, but in order to store heat, the laser may be moved so that the same place is not continuously irradiated after a lapse of a predetermined time. .. By using a laser, microfabrication can be performed and the position accuracy of the cut portion can be maintained high. The intensity of the laser beam, the diameter of the irradiation spot, and the moving speed of the irradiation spot are determined on the first coating member 2 in consideration of the thermal conductivity of the first coating member 2 and the conductive layer 25 and the difference in thermal conductivity between them. It can be set so that laser ablation occurs in the conductive layer 25.

The wavelength of the laser beam is an infrared region (for example, around 1064 nm), a laser in the red region (for example, around 640 nm), a laser in the green region (for example, around 532 nm), and a blue region or an ultraviolet region (for example, 355 nm) shorter than the green region. A laser having an emission wavelength of (near) may be used. In the ultraviolet region, this makes it possible to efficiently generate ablation and improve mass productivity. Further, the pulse width of the laser can be nanoseconds, picoseconds, femtoseconds, or the like. For example, it is preferable to use a laser having a pulse width of nanoseconds in the green region near 532 nm from the viewpoint of output and work efficiency.

It is preferable to irradiate a laser beam having a width narrower than the distance between the pair of electrodes 5. For example, the distance between the first electrode 5a and the second electrode 5b is set to 30 μm, and the distance between the first wiring 20a and the second wiring 20b is set to 30 μm by using a laser with a processing width of about 30 μm. Can be done. It is preferable to irradiate the laser beam from a direction perpendicular to the conductive layer 25 at 90 degrees, but it is preferable to irradiate the conductive layer 25 from an oblique direction of 45 to 145 degrees, preferably 70 to 110 degrees. ..

The resin and carbon particles of the conductive layer 25 are scattered by the laser irradiation and therefore collect dust. It is preferable to collect dust in a direction parallel to the light guide plate 30 or at an angle of 30 degrees or less with respect to the light guide plate 30.

The first covering member 2 is arranged on the first surface of the light emitting element 1 and between the pair of electrodes 5, and in the step of forming the pair of wirings 20, the first surface of the light emitting element 1 and the pair The first covering member 2 arranged between the electrodes 5 of the above is preferably partially removed by a laser beam. That is, the first covering member 2 arranged between the pair of electrodes 55 is not completely removed by the laser beam, and a part of the first covering member 2 remains. Since the first covering member 2 is insulating, it is possible to prevent a short circuit between the first wiring 20a and the second wiring 20b due to the remaining first covering member 2. The thickness of the remaining first covering member 2 is preferably 1/5 or more and 4/5 of the thickness of the electrode 5. Further, the surface of the first covering member 2 between the pair of electrodes 5 partially removed by the laser beam preferably has irregularities of 100 nm or more and 3 μm or less, preferably 500 nm or more and 1 μm or less. Since the carbon particles have a small particle size, the conductive layer can be easily removed by irradiating the laser beam, so that the surface of the first coating member 2 is not significantly roughened.

Here, in the laser irradiation method, a plurality of light emitting elements 1 are arranged side by side in the row direction and the column direction on the light guide plate 30. A conductive layer 25 having a predetermined width is arranged on the light emitting element 1. Then, a laser beam is irradiated between the pair of electrodes 5 of the light emitting element 1. By arranging the light emitting element 1 at a predetermined position, the pair of electrodes 5 of the light emitting element 1 cannot be directly visually recognized, but laser irradiation can be performed between the pair of electrodes 5. At this time, in consideration of the deviation of the laser irradiation, it is preferable to set the space between the pair of electrodes 5 to be about 1.5 to 5 times wider than the pulse width of the laser.

As a different method, first, the pair of electrodes 5 of the light emitting element 1 are recognized in the step of preparing the intermediate, and in the step of forming the pair of wirings, the pair of electrodes of the light emitting element 1 recognized in the step of preparing the intermediate. A method of irradiating a laser beam between 5 is preferable. By recognizing the positions of the pair of electrodes 5 of the light emitting element 1 in advance in this way, the laser beam is irradiated 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. Therefore, it is possible to set a narrow space between the pair of electrodes 5 and use a small light emitting element 1.

After the step of forming the pair of wirings, a step of covering at least the pair of electrodes 5 with the insulating member 60 may be further included. Since the pair of electrodes 5 may be exposed by laser ablation, a short circuit can be prevented by covering the pair of electrodes 5 with the insulating member 60. The insulating member 60 may cover not only the pair of electrodes 5 but also the pair of wirings 20, the second covering member 50, and the like. In the step of covering the pair of electrodes 5 with the insulating member 60, the insulating member 60 is preferably colored. The insulating member 60 may be transparent, translucent, or 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 visually. It is preferable to use a spectrophotometer as the measuring instrument. For example, the spectrophotometer preferably uses blue light having a peak wavelength of 480 nm, green light having a peak wavelength of 520 nm, red light having a peak wavelength of 600 nm, or the like, but is not limited to this wavelength. Further, the insulating member 60 is preferably colorless and transparent, but it is confirmed that the insulating member 60 is arranged on the first covering member 2 or the like, or the connection state of the wiring 20 is confirmed through the insulating member 60. It is particularly preferable that it is colored to the extent that it can be used. For example, it is preferable that the insulating member 60 contains a coloring material such as blue, green, or red, a pigment, a pigment, or a dye. The light transmittance of the insulating member 60 can be, for example, 20% or more and 95% or less, preferably 30% or more and 80% or less. A transmittance measuring device is used for the light transmittance of the insulating member 60. The insulating member 60 is preferably in the form of a film, and the thickness of the insulating member 60 is preferably 0.5 μm to 100 μm. The size of the insulating member 60 is preferably a circle, an ellipse, a rectangle, or the like having a maximum diameter of 0.5 to 3 times the maximum diameter of the package 10.

By going through the above steps, the light emitting device of the embodiment can be manufactured. This makes it possible to provide a highly reliable manufacturing method of a light emitting device while being a small light emitting device.

The light emitting device of the embodiment includes a light emitting element 1 having a pair of electrodes 5 on the first surface side, a first covering member 2 covering the light emitting element 1 so that a part of the surface of the pair of electrodes 5 is exposed, and an exposed light emitting device. The pair of electrodes 5 and the first covering member 2 are continuously covered, and the pair of electrodes 5 have a pair of wirings 20 that are not electrically connected to each other, and the pair of wirings 20 have a plurality of wirings 20. Resin is contained in the carbon particles, or only carbon particles. This makes it possible to provide a small light emitting device. Further, it is possible to provide a light emitting device having high conductivity. Here, "the pair of electrodes are not electrically connected to each other" means that the pair of electrodes, which are different types of electrodes, are not short-circuited.

It is preferable that the first translucent member 3 is arranged on the second surface side of the light emitting element 1 opposite to the first surface, and the first translucent member 3 is arranged on the light guide plate 30. As a result, the light from the light emitting element 1 can be spread through the light guide plate 30. Further, when the first translucent member 3 contains a phosphor, a desired color can be realized.

It is preferable that the second translucent member 4 is provided on the side surface connected to the first surface and the second surface of the light emitting element 1. As a result, the light emitted from the side surface of the light emitting element 1 can be easily emitted in the direction directly above the first surface.

The surface of the first covering member 2 arranged between the pair of electrodes 5 preferably has irregularities of 100 nm or more and 3 μm or less, preferably 500 nm or more and 1 μm or less. Since the carbon particles have a small particle size, the conductive layer can be easily removed by irradiating the laser beam, so that the surface of the first coating member 2 is not significantly roughened.

The pair of electrodes 5 is preferably covered with an insulating member 60. This is because a short circuit between the pair of electrodes 5 can be suppressed.

In the pair of wirings 20, the concentration of carbon particles is preferably 50% by volume or more and 100% by volume or less, and more preferably 80% by volume or more. By increasing the concentration of carbon particles, the conductivity can be increased and the electrical resistance can be suppressed to a low level.

The thickness of the pair of wirings 20 is preferably 5 μm or more, preferably 10 μm or more, and particularly preferably 12 μm or more, 15 μm or more, and 20 μm or more. 50 μm or less is preferable, and 35 μm or less and 30 μm or less are particularly preferable. This is because a thin light emitting device having a predetermined thickness can be provided. In particular, it is preferably formed to be 20 μm or more, and particularly preferably 25 μm or more and 30 μm or less.

There are a plurality of light emitting elements 1 used in the light emitting device, and a pair of wirings 20 are formed on each of the plurality of light emitting elements 1. It is preferable that at least two or more pairs of wirings 20 are electrically connected by a metal paste layer containing metal particles in the resin or a metal layer formed only of metal to form a pair of wirings 20. Only the wiring of the portion of the light emitting element 1 that irradiates the laser beam contains carbon particles, and the wiring that connects the plurality of light emitting elements or the light emitting element and the external electrode is not irradiated with the laser light, so that the metal paste layer is used. Alternatively, the wiring can be formed of a metal layer. As a result, the electrical resistance value of the wiring can be significantly reduced.

Package 10
The package 10 includes at least a light emitting element 1 and a first covering member 2, and can also include a first translucent member 3, a second translucent member 4, and the like. The light emitting element 1 includes a pair of electrodes 5 on the first surface. Since the first covering member 2 covers the side surface of the light emitting element 1, it may be insulating. The first covering member 2 is preferably reflective, but may be translucent. As the reflective first coating member 2, for example, a member or the like in which silica and white titanium oxide are contained in a silicone resin in an amount of about 60 wt% can be used, and is formed by compression molding, transfer molding, injection molding, printing, spraying or the like. can do. Further, the first covering member can be formed into a plate shape and cut into a predetermined size to form a rectangular parallelepiped.

A liquid second translucent member 4 is applied onto the first translucent member 3 of the plate-shaped member, and the plurality of light emitting elements 1 are adhered to each other. The liquid second translucent member 4 is formed so as to be separated from each other. Each second translucent member 4 can have an arbitrary shape in a plan view corresponding to the shape of the light emitting element 1, and examples thereof include a square, a rectangle, a circle, and an ellipse. The distance between the adjacent second translucent members 4 can be appropriately set according to the outer shape of the package 10 and the number of packages 10 to be taken. Further, the second translucent member 4 is preferably formed so as to cover about 70% to 150% of the area of the first translucent member 3 of the plate-shaped member.

When the light emitting element 1 is arranged on the liquid first translucent member 3, the second translucent member 4 crawls up the side surface of the light emitting element 1. As a result, when the light emitting element 1 is placed on the first translucent member 3, the outer surface of the second translucent member 4 is shaped to face diagonally upward. For example, the combined form of the second translucent member 4 and the light emitting element is a quadrangular pyramid. After arranging the light emitting element 1 on the first translucent member 3, the light emitting element 1 may be pressed, if necessary. After arranging the light emitting element 1, the liquid second translucent member 4 is heated to form the cured second translucent member 4.

Although the second translucent member 4 also exists between the light emitting element 1 and the first translucent member 3, it can be directly joined without using the second translucent member 4.

Next, the package 10 is arranged on the light guide plate 30 via the third translucent member 40 so that the first translucent member 3 comes into contact with the light guide plate 30. The second covering member 50 is provided so as to integrally cover the plurality of packages 10. As the second coating member 50, for example, a member or the like in which silica and white titanium oxide are contained in about 60 wt% in the silicone resin can be used, and can be formed by compression molding, transfer molding, injection molding, printing, spraying or the like. it can.

The entire second covering member 50 is covered so as to cover the package 10 arranged on the light guide plate 30, and after the second covering member 50 is cured, the pair of electrodes 5 of the light emitting element 1 are exposed. , The thickness of the second covering member 50 may be reduced by a known processing method. As a result, the package 10 having a predetermined thickness can be obtained. Further, the heights of the pair of electrodes 5 and the second covering member 50 can be made uniform, so that the conductive layer 25 can be easily printed.

Here, the term "plate-shaped" refers to a member having a large area on which a light emitting element can be placed, and may be paraphrased by terms such as sheet-shaped, film-shaped, and layered.

Light emitting element 1
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 capable of emitting visible light such as blue, green, and red can be used. The semiconductor light emitting device includes a laminated structure including a light emitting layer and electrodes. The laminated structure includes a first surface on the side where the electrodes are formed, and a second surface as a light extraction surface on the opposite side.

The laminated structure includes a semiconductor layer including a light emitting layer. Further, a translucent substrate such as sapphire may be provided. As an example of the semiconductor laminate, three semiconductor layers of a first conductive type semiconductor layer (for example, n-type semiconductor layer), a light emitting layer (active layer), and a second conductive type semiconductor layer (for example, p-type semiconductor layer) are included. Can be done. The semiconductor layer capable of emitting visible light from ultraviolet light or blue light to green light can be formed from a semiconductor material such as a group III-V compound semiconductor. Specifically, _{a nitride-based semiconductor material such as In X} Al _Y Ga _1-XY N (0 ≦ X, 0 ≦ Y, X + Y ≦ 1) can be used. As the semiconductor laminate capable of emitting red light, GaAs, GaAlAs, GaP, InGaAs, InGaAsP and the like can be used. The electrode is preferably copper.

1st covering member 2
The first coating member 2 is preferably a resin member containing, for example, a thermosetting resin such as a silicone resin, a silicone-modified resin, an epoxy resin, a phenol resin, or a urea resin as a main component.

The first covering member 2 is preferably a light-reflecting resin member. The light-reflecting resin means a resin material having a reflectance of 70% or more with respect to light from a light emitting element. For example, a white resin or the like is preferable. The light that has reached the first covering member is reflected and directed toward the light emitting surface of the light emitting device, so that the light extraction efficiency of the light emitting device can be improved. Further, the first covering member 2 may be a translucent resin member. As the first covering member in this case, the same material as the first translucent member described later can be used.

As the light-reflecting resin, for example, a translucent resin in which a light-reflecting substance is dispersed can be used. As the light-reflecting substance, for example, titanium oxide, silicon oxide, zirconium oxide, potassium titanate, aluminum oxide, aluminum nitride, boron nitride, mullite and the like are suitable. As the light-reflecting substance, granular, fibrous, thin plate pieces and the like can be used, but the fibrous material is particularly preferable because it can be expected to have an effect of reducing the coefficient of thermal expansion of the first coating member.

When the first coating member is composed of a resin member containing a filler such as a light-reflecting substance, the resin component on the surface irradiated with the laser is removed by ablation to expose the filler on the surface. Further, by continuously or sequentially moving the irradiation spot of the laser beam on the surface, a striped groove is formed in the moving direction. This groove is formed to a depth of 0.1 to 3 μm, for example, with a width of about 10 to 100 μm, typically 40 μm, depending on the irradiation spot diameter of the laser beam.

The first covering member 2 may use the same material as the first translucent member 3, and may contain a phosphor as a wavelength conversion member in addition to the following translucent material. As the phosphor, a phosphor that can be excited by light emission from the light emitting element is used. Not only the first translucent member containing a phosphor is arranged only on the second surface of the light emitting element, but also the second translucent member containing a phosphor is arranged on the side surface of the light emitting element, thereby causing the light emitting element. And because the light from the phosphor can be spread laterally.

First translucent member 3
The first translucent member 3 is arranged on the second surface of the light emitting element. As the material of the first translucent member 3, resin, glass or the like can be used. As the resin, a thermosetting resin such as a silicone resin, a silicone modified resin, an epoxy resin or a phenol resin, a thermoplastic resin such as a polycarbonate resin, an acrylic resin, a methylpentene resin or a polynorbornene resin can be used. In particular, a silicone resin having excellent light resistance and heat resistance is preferable.

The first translucent member 3 may include a phosphor as a wavelength conversion member in addition to the translucent material described above. As the phosphor, a phosphor that can be excited by light emission from the light emitting element is used. For example, as a phosphor that can be excited by a blue light emitting element or an ultraviolet light emitting element, an yttrium aluminum garnet fluorescent substance (YAG: Ce) activated by cerium; a lutetium aluminum garnet fluorescent substance activated by cerium is used. (LAG: Ce); nitrogen-containing calcium aluminosilicate-based phosphor activated with europium and / or chromium (CaO-Al ₂ O _3- SiO ₂ ); silicate-based phosphor activated with europium ((Sr, Ba)) ₂ SiO _{4); β-sialon} phosphor, CASN phosphor, nitride-based phosphor such as SCASN phosphor; KSF phosphor _{(K 2 SiF 6: Mn)} ; sulphide phosphor, a quantum dot phosphor And so on. By combining these phosphors with a blue light emitting element or an ultraviolet light emitting element, a light emitting device of various colors (for example, a white light emitting device) can be manufactured. The first translucent member 3 may be a fluorescent material alone as a wavelength conversion member instead of the translucent material described above.

Further, the first translucent member 3 may contain various fillers and the like for the purpose of adjusting the viscosity and the like.

Second translucent member 4
The second translucent member 4 adheres the light emitting element 1 and the first translucent member 3. The second translucent member may contain a phosphor or a filler.

It goes without saying that the present invention is not limited to the above-described embodiments, and can be arbitrary as long as it does not deviate from the gist of the present invention.

Light guide plate 30
The light guide plate 30 is not limited to a flat plate shape, but may have some concave portions or convex portions. The package can be placed in the recess. Further, the concave portion and the convex portion may have a function such as a lens. Further, a dent, a light-shielding film, a reflective film, or the like may be formed so that the light guide plate 30 has a parting property. By providing a reflective film or a light-shielding film on the opposite side of the light guide plate on which the package is arranged, the light from the package can be spread in the horizontal direction through the light guide plate.

The light emitting device according to the second embodiment will be described with reference to the drawings. FIG. 5 is a schematic perspective view from the light guide plate side of the light emitting device according to the second embodiment. FIG. 6 is a schematic cross-sectional view of the light emitting device according to the second embodiment. FIG. 7 is a schematic plan view of the light emitting device according to the second embodiment. The schematic perspective view of the light emitting device according to the second embodiment constitutes one segment consisting of a total of 16 cells, 4 cells in the vertical direction and 4 cells in the horizontal direction. By combining a plurality of these segments, a planar light source of any size can be obtained. The schematic cross-sectional view of the light emitting device according to the second embodiment shows one cell.

A predetermined light guide plate 31 is used for the light emitting device according to the second embodiment. The light guide plate 31 has a flat surface on the side on which the package 10 is arranged and a back surface on the opposite side to the flat surface. The light of the package 10 is mainly emitted from the back surface side of the light guide plate 31. One cell of the light guide plate 31 has a first recess 31a in a region where the package 10 is arranged. A second recess 31b is arranged between the adjacent first recesses 31a in the light guide plate 31, and the second recess 31b has a grid shape formed by the intersection of vertical and horizontal straight lines. In the package 10, the light emitting element 1 is placed on the first translucent member 3, the second translucent member 4 is arranged on the side surface of the light emitting element 1, and the first covering member covers the second translucent member 4. 2 is arranged. The first recess 31a has a quadrangular pyramid shape in a plan view, and has a trapezoidal shape in which the upper part of the opening is wider than the bottom side in a cross-sectional view. 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 trapezoid is in contact with the first translucent member 3. A third translucent member 40 is arranged on the side surface of the package 10. A reflective member 70 is arranged in the second recess 31b of the light guide plate 31. The upper surface of the reflective member 70 and the flat surface of the light guide plate 31 are covered with the second covering member 50. The reflective member 70 and the second covering member 50 are mixed with a light-reflecting substance in the resin so as to efficiently reflect the light from the package 10, and the light from the package 10 is emitted from the back surface side of the light guide plate 31. ing. Further, the second recess 31b is provided with an inclination so that the light from the package 10 can be easily emitted from the back surface side of the light guide plate 31, and preferably the light can be taken out in the direction perpendicular to the back surface of the light guide plate 31. Tilt angle is preferable. Wiring 21 is provided on the second covering member 50. The wiring 21 contains resin in a plurality of carbon particles, or is only carbon particles. However, since the solvent may be contained together with the resin and the solvent is removed by heating when the resin is cured, the solvent does not remain, or even if it remains, the residue is small. The first wiring 21a is electrically connected to the first electrode 5a of the package 10, the second wiring 21b is electrically connected to the second electrode 5b of the package 10, and these connecting portions are covered with an insulating member 60. .. At this time, the second recess 31b has the deepest space between the adjacent first recesses 31a, that is, the joint between the cells. Since the reflective member 70 is arranged in the second recess 31b, the resin used in the reflective member 70 is cured and the resin sinks, and a curved recess is formed on the upper surface of the reflective member 70 of the second recess 31b. It will be easier. Therefore, when the wiring 21 is printed or the like, the wiring may be easily broken. Therefore, a wide portion 21c is provided as a part of the wiring 21. Even if the wiring 21 is not broken, there is a risk that the wiring 21 will be blurred or the wiring will be thin when printing, and the electrical resistance will increase. Therefore, it is preferable to provide the wide portion 21c of the wiring 21 in the vicinity of the most recessed portion of the second recess 31b or at the joint between the cells. Further, the wide portion 21c of the wiring 21 is not limited to a circular or elliptical shape, but may be a rectangle or a polygon, and may be not limited to one but may be a plurality of wires or a plurality of wires. When a plurality of wide portions 21c are provided at the joint between cells, it is preferable to arrange the plurality of wide portions 21c in a substantially linear shape. However, although the conductive layer containing carbon particles is irradiated with laser light to cause laser ablation, the laser output can be suppressed to a low level, so that the thickness of the wiring 21 containing carbon particles and the like can be increased.

The back surface 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 conical or polygonal pyramid, for example. This is because the light emitted from the package 10 spreads horizontally or diagonally through the light guide plate 31 by forming the third recess 31c into a conical shape or the like. A light-shielding member 80 may be provided in the third recess 31c. Since the light emitted from the package 10 is emitted most strongly directly above, uneven light emission is likely to occur when the light guide plate 31 as a whole is viewed. Therefore, by providing the light-shielding member 80 in the third recess 31c, it is possible to suppress the light directly above the package 10 and reduce the light emission unevenness. The light-shielding member 80 may cover the entire third recess 31c, but it is preferable that only a part of the third recess 31c, for example, the depth of the third recess 31c is about 1/4 to 3/4. It is preferable that the light-shielding member 80 is covered with the same or twice as much as the first recess 31a in the rear view of the light guide plate 31. The third recess 31c after the light-shielding member 80 is provided in the third recess 31c preferably has a truncated cone shape in the rear view.

Therefore, the light guide plate 31 includes a plurality of first recesses 31a in which the light emitting element 1 is arranged, and a second recess 31b between the adjacent first recesses 31a, and the reflection member 70 is arranged in the second recess 31b. The second covering member 50 that covers the reflective member 70 is arranged, and the wiring 21 is arranged on the second covering member 50. The wiring 21 arranged on the second recess 31b preferably includes a portion wider than the wiring 21 arranged on the first recess 31a, a wide portion 21c.

The light emitting device according to the third embodiment will be described with reference to the drawings. FIG. 8 is a schematic plan view of the light emitting device according to the third embodiment.

The light emitting device according to the third embodiment adopts substantially the same embodiment except that the wiring according to the second embodiment is different. The wiring 22 is provided with a wide portion 22c between the packages 10 adjacent to each other in the lateral direction, particularly at a position in the middle of the adjacent packages 10. Near the center of the wiring 22 in the lateral direction, a bent portion is provided between the adjacent packages 10, but a bent portion is provided at a portion deviated from the intermediate position of the adjacent packages 10. .. By bending the wiring 22, it is possible to suppress faintness and disconnection during printing. Further, a wiring portion 22d having a wide 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 widening the wire width of the wiring 22, the electrical resistance can be lowered and the disconnection can be prevented. The length of the wiring portion 22d in the lateral direction is not particularly limited, but it is preferable that the wiring portion 22d extends to the vicinity of the wide portion 22c in the vertical direction.

As a test example, a wiring in which a plurality of carbon particles are arranged is formed on a test piece. This wiring corresponds to a pair of wirings arranged on the light emitting element. A conductive layer containing a predetermined conductive substance containing a resin and a solvent is formed on a test piece, a predetermined temperature is applied to cure the resin, and after removing the solvent, the conductive layer is irradiated with laser light to conduct conductivity. A part of the layer is removed to form a pair of wires. Prepare several thicknesses of the conductive layer and check the upper limit of wiring formation. A UV laser having a wavelength of 355 nm was used as the laser light condition, and the processing was performed under the conditions of a laser power of 1 W, a transmission frequency of 100 KHz, and a scan speed of 1000 mm / S. The electrical resistance value was 30 μm in a 1 cm square as a test piece, paste-printed, and the resistance was measured by the 4-terminal method to obtain the volume specific resistance.

9A to 9C are cross-sectional photographs of Test Examples 1 to 3. FIG. 10 is a cross-sectional photograph of Reference Example 1. The whitish particles in the photograph are metal particles, and the blackish particles are carbon particles.

In the wiring of Test Example 1, a conductive layer containing a plurality of carbon particles in a solvent is formed on the test piece. The thickness of one conductive layer is 15 μm. As Test Example 2, the conductive layer contains carbon particles and copper particles in a solvent at a weight ratio of 50:50. The volume ratio of carbon particles to copper particles is 83:17. The copper particles are spherical with a size of about 2 μm. As Test Example 3, the conductive layer contains carbon particles and copper particles in a solvent at a weight ratio of 50:50. The volume ratio of carbon particles to copper particles is 83:17. The copper particles are flat with a maximum diameter of about 3 μm. As Test Example 4, the conductive layer contains carbon particles and copper particles in a solvent at a weight ratio of 40:60. The volume ratio of carbon particles to copper particles is 77:23. The copper particles are flat with a maximum diameter of about 3 μm. As Test Example 5, the conductive layer contains carbon particles and copper particles in a solvent at a weight ratio of 30:70. The volume ratio of carbon particles to copper particles is 68:32. The copper particles are flat with a maximum diameter of about 3 μm. As Test Example 6, the conductive layer contains carbon particles and copper particles in a solvent at a weight ratio of 20:80. The volume ratio of carbon particles to copper particles is 56:44. The copper particles are flat with a maximum diameter of about 3 μm.

As a reference example 1, the conductive layer contains only copper particles in a solvent. The copper particles are spherical with a size of about 2 μm.

In Reference Example 1, the electric resistance value is as ^{low as 1 × 10 -4} Ωcm, but it is difficult to cut the conductive layer by laser light, and the limit is about 10 μm.

On the other hand, in Test Examples 1 to 6, the conductive layer was easily cut by the laser beam, and the limit was higher than 10 μm. In Test Example 3, the electric resistance value was 0.05 Ω · cm, but the conductive layer was easily cut by the laser beam, and the limit was as high as 30 μm. In Test Example 2, the electric resistance value was 0.5 Ω · cm, but the conductive layer was easily cut by the laser beam, and the limit was as high as 30 μm. This is a difference depending on whether the copper particles are spherical or flat, but it is considered that the use of the flat shape increases the contact area between the copper particles and lowers the electrical resistance value. Further, in Test Example 1, the electric resistance value was as high as 1 Ω · cm, but the limit was 50 μm or more, and the thickness of the conductive layer could be increased. In this way, the thickness of the conductive layer can be increased to reduce the risk of disconnection and suppress the laser output.

The light emitting device according to the present embodiment can be used for a backlight, a lighting device, or the like.

1 Light emitting element 2 1st covering member 3 1st translucent member 4 2nd translucent member 5 Electrode 5a 1st electrode 5b 2nd electrode 10 Package 20, 21, 22 Wiring 20a, 21a 1st wiring 20b, 21b 1st 2 Wiring 20c, 21c Wide part 22d Wiring part 25 Conductive layer 30, 31 Light guide plate 31a 1st recess 31b 2nd recess 31c 3rd recess 40 3rd translucent member 50 2nd covering member 60 Insulating member 70 Reflecting member 80 Shading Member 100 Light emitting device

Claims (25)

A step of preparing an intermediate including a light emitting element having a pair of electrodes on the first surface side and a first covering member covering the light emitting element so that a part of the surface of the pair of electrodes is exposed. ,
A step of forming a conductive layer that continuously covers the pair of exposed electrodes and the first covering member.
By irradiating the conductive layer on the pair of electrodes and the conductive layer on the first coating member with laser light, one of the conductive layer between the pair of electrodes and the conductive layer on the first coating member. A step of removing the portion and forming a pair of wirings so that the pair of electrodes are not short-circuited.
Including
A method for manufacturing a light emitting device, wherein the conductive layer used in the step of forming the conductive layer is one in which a resin or a solvent is contained in a plurality of carbon particles, or only carbon particles. The method for manufacturing a light emitting device according to claim 1, further comprising a step of covering at least the pair of electrodes with an insulating member after the step of forming the pair of wirings. The method for manufacturing a light emitting device according to claim 1 or 2, wherein the step of forming the pair of wiring includes a step of irradiating the laser beam having a width narrower than the distance between the pair of electrodes. The method for manufacturing a light emitting device according to any one of claims 1 to 3, wherein the step of forming the conductive layer includes a step of forming by either printing or spraying. In the step of preparing the intermediate
The light emitting element has a first translucent member arranged on the second surface side opposite to the first surface.
The method for manufacturing a light emitting device according to any one of claims 1 to 4, wherein the first translucent member is arranged on a light guide plate. In the step of preparing the intermediate, the first coating member is arranged on the first surface of the light emitting element and between the pair of electrodes.
In the step of forming the pair of wirings, the first covering member arranged on the first surface of the light emitting element and between the pair of electrodes is partially removed by the laser beam. The method for manufacturing a light emitting device according to any one of claims 5. In the step of preparing the intermediate, the pair of electrodes of the light emitting element are recognized and
The item according to any one of claims 1 to 6, wherein the laser beam is irradiated between the pair of electrodes of the light emitting element recognized in the step of preparing the intermediate in the step of forming the pair of wirings. The method for manufacturing a light emitting device according to the description. In the step of preparing the intermediate, a plurality of the light emitting elements are used.
In the step of forming the conductive layer, the plurality of light emitting elements are continuously covered with each other.
The method for manufacturing a light emitting device according to any one of claims 1 to 7, wherein the plurality of light emitting elements are electrically connected in the step of forming the wiring. When the conductive layer contains a solvent in a plurality of carbon particles,
The method for manufacturing a light emitting device according to claim 1, further comprising a step of removing the solvent after the step of forming the conductive layer and before the step of forming the wiring. The method for manufacturing a light emitting device according to any one of claims 1 to 9, wherein the carbon particles contain at least 50% by volume or more of a flat shape or a needle shape. The method for manufacturing a light emitting device according to claim 9 or 10, wherein the conductive layer used in the step of forming the conductive layer has a concentration of carbon particles of 80% by volume or more and 100% by volume or less. The method for manufacturing a light emitting device according to any one of claims 1 to 11, wherein in the step of forming the conductive layer, the thickness of the conductive layer is formed to be 12 μm or more and 50 μm or less. The method for manufacturing a light emitting device according to claim 9, wherein the carbon particles are particles having a maximum diameter of 0.01 μm or more and 10 μm or less. In the step of forming the conductive layer, the conductive layer is formed separately on the plurality of light emitting elements.
Before or after the step of forming the pair of wirings, at least two or more of the conductive layers are electrically connected by a metal paste layer containing metal particles in a resin or a metal layer formed only of metal, and said. The method for manufacturing a light emitting device according to any one of claims 1 to 13, wherein a pair of wirings is formed. The light guide plate includes a plurality of first recesses in which the light emitting element is arranged, and a second recess between adjacent first recesses, and a reflective member is arranged in the second recess. A second covering member covering the reflective member is arranged, and the wiring is arranged on the second covering member.
The method for manufacturing a light emitting device according to claim 5, wherein the wiring arranged on the second recess includes a portion wider than the wiring arranged on the first recess. A light emitting element having a pair of electrodes on the first surface side,
A first coating member that covers the light emitting element so that a part of the surface of the pair of electrodes is exposed.
The pair of exposed electrodes and the first covering member are continuously covered, and the pair of electrodes have a pair of wirings that are not electrically connected to each other.
The pair of wirings on the light emitting element is a light emitting device in which a resin is contained in a plurality of carbon particles or only carbon particles. The light emitting element has a first translucent member arranged on the second surface side opposite to the first surface.
The light emitting device according to claim 16, wherein the first translucent member is arranged on a light guide plate. The light emitting device according to claim 16 or 17, wherein a second translucent member is provided on a side surface of the light emitting element that is connected to the first surface and the second surface. The light emitting device according to any one of claims 16 to 18, wherein the surface of the first coating member arranged between the pair of electrodes has irregularities of 100 nm or more and 3 μm or less. The light emitting device according to any one of claims 16 to 19, wherein the pair of electrodes is covered with an insulating member. The light emitting device according to any one of claims 16 to 20, wherein the pair of wirings has a concentration of carbon particles of 50% by volume or more and 100% by volume or less. The light emitting device according to any one of claims 16 to 21, wherein the thickness of the pair of wirings is 12 μm or more and 50 μm or less. The light emitting device according to any one of claims 16 to 22, wherein the carbon particles contain at least 50% by volume or more of a flat shape or a needle shape. The light emitting device according to any one of claims 16 to 23, wherein the carbon particles include particles having a maximum diameter of 0.01 μm or more and 10 μm or less. There are a plurality of the light emitting elements,
The pair of wirings are formed separately on the plurality of light emitting elements.
16 to 16 to claim that the pair of wirings of at least two or more are electrically connected by a metal paste layer containing metal particles in a resin or a metal layer formed only of metal to form the pair of wirings. The light emitting device according to any one of 24.

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