JP2022075717A - Light-emitting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light-emitting device which has improved light extraction efficiency.

SOLUTION: A method for manufacturing a light-emitting device includes: a step (A) of preparing a light-emitting body 100U including a light-emitting element 110A and a translucent member 140U that covers the light-emitting element and has an upper surface 140a, in which the translucent member contains a silicone resin; a step (B) of making a plurality of first projections 210 of a mold 200 having the plurality of first projections opposite to the upper surface of the translucent member, pressing a mold against the upper surface of the translucent member in a heated state, and thereby forming a plurality of recesses 141q each having a bottom surface 141b on the upper surface; a step (C) of forming a plurality of finer second recesses 142q on a region other than the plurality of first recesses on the upper surface of the translucent member and at least a bottom surface in the plurality of first recesses after the step (B); and a step (D) of irradiating the translucent member with ultraviolet rays from the upper surface side after the step (C).

SELECTED DRAWING: Figure 6

COPYRIGHT: (C)2022,JPO&INPIT

Description

The present disclosure relates to a method for manufacturing a light emitting device and a light emitting device.

A light emitting device having a semiconductor light emitting element typified by an LED is widely used. In such a light emitting device, it is common to seal a chip such as an LED with a translucent resin. For example, Patent Document 1 below discloses a light emitting device in which a semiconductor light emitting device is sealed with a translucent member such as a transparent resin and a phosphor layer is arranged on the translucent member.

Patent Document 1 proposes to provide a plurality of concave portions and / or convex portions on the upper surface of the phosphor layer located on the opposite side of the light emitting element. In the technique described in Patent Document 1, the light from the light emitting element is incident on the side surface defining the concave portion or the convex portion, thereby avoiding the confinement of the light due to total reflection and improving the light extraction efficiency. In addition, these concave portions and convex portions are formed, for example, by filling a liquid resin material containing a phosphor in a molding die and then heat-curing the resin material (paragraph 0027). The phosphor layer having concave portions and / or convex portions formed on the surface is fixed above the light emitting element via a translucent member such as a transparent resin.

Japanese Unexamined Patent Publication No. 2006-237264

In the field of light emitting devices, there is a demand for improved brightness.

The method for manufacturing a light emitting device according to an embodiment of the present disclosure is a step of preparing a light emitting body including a light emitting element and a light transmitting member that covers the light emitting element and has a top surface, and the light transmitting member is made of silicone. In the step (A) containing the resin, the plurality of first convex portions of the mold having the plurality of first convex portions are made to face the upper surface of the translucent member, and the transmissive member is heated. By pressing the mold against the upper surface, a plurality of first recesses each having a bottom surface are formed on the upper surface, and after the step (B), a plurality of finer second recesses are formed. From the upper surface side after the step (C) of forming at least the bottom surface of the plurality of first recesses and the region other than the plurality of first recesses in the upper surface of the translucent member and the step (C). The step (D) of irradiating the translucent member with ultraviolet rays is included.

A method of manufacturing a light emitting device according to another embodiment of the present disclosure is a step of preparing a light emitting body including a light emitting element and a light transmitting member that covers the light emitting element and has an upper surface. The plurality of first convex portions and the plurality of the first convex portions of the mold having the plurality of first convex portions and the plurality of second convex portions finer than the first convex portions, which contain the silicone resin. A step (B) of forming a plurality of concave portions in the translucent member by making the second convex portion face the upper surface of the translucent member and pressing the mold against the upper surface of the transmissive member in a heated state. ) And the step (C) of irradiating the translucent member with ultraviolet rays from the upper surface side after the step (B), wherein the plurality of recesses are a plurality of first recesses each having a bottom surface. The plurality of second recesses include a plurality of second recesses finer than the plurality of first recesses, and in the step (B), the plurality of second recesses include the plurality of first recesses of the upper surface of the translucent member. It is formed on a region other than the provided region and on the bottom surface of the plurality of first recesses.

A light emitting device according to still another embodiment of the present disclosure includes a light emitting element and a translucent member having an upper surface and covering the light emitting element, and the upper surface of the transmissive member has a bottom surface and one or more, respectively. Each first recess has a plurality of second recesses finer than the first recess on the bottom surface and the one or more side surfaces.

According to an embodiment of the present disclosure, there is provided a light emitting device having improved light extraction efficiency.

It is a schematic perspective view which shows an example of the appearance of the light emitting device by an embodiment of this disclosure. It is a figure which shows typically the cross section of the light emitting apparatus 100A shown in FIG. It is a schematic perspective view which shows typically the upper surface 100a of a light emitting device 100A. It is a schematic sectional drawing which enlarges and shows a part of the translucent member 140A near the upper surface 140a. It is a figure which shows an example of the shape of the 2nd recess 142 schematically. It is a flowchart which shows the outline of the manufacturing method of the light emitting device by an embodiment of this disclosure. It is a schematic cross-sectional view for demonstrating an exemplary manufacturing method of a light emitting device according to an embodiment of the present disclosure. It is a schematic perspective view which shows an example of the mold 200 which has a plurality of first convex portions 210 on one main surface 200b. It is a schematic cross-sectional view for demonstrating an exemplary manufacturing method of a light emitting device according to an embodiment of the present disclosure. It is a schematic cross-sectional view which shows the light emitting body 100U after pulling out a mold 200 from a translucent member 140U. It is a schematic diagram for demonstrating the process of forming a plurality of second recesses by irradiation of a laser beam. It is a schematic cross-sectional view for demonstrating an exemplary manufacturing method of a light emitting device according to an embodiment of the present disclosure. It is a schematic diagram for demonstrating the method of forming a plurality of second recesses 142q by exposing the upper surface 140a of the translucent member 140U to the treatment liquid 450. It is a schematic cross-sectional view which shows the modification of the light emitting device by an embodiment of this disclosure. It is a flowchart which shows the outline of the manufacturing method of the light emitting device by another embodiment of this disclosure. It is a schematic perspective view which shows an example of the mold 200A which has a plurality of first convex portions 210 and a plurality of second convex portions 220 finer than the first convex portion 210 on one main surface 200b. FIG. 16 is a schematic perspective view showing an enlarged view of the first convex portion 210 of the mold 200A shown in FIG. 16 and its periphery thereof. It is a schematic cross-sectional view for demonstrating an exemplary manufacturing method of a light emitting device according to another embodiment of the present disclosure. It is a schematic cross-sectional view for demonstrating the exemplary manufacturing method of a light emitter. It is a schematic cross-sectional view for demonstrating the exemplary manufacturing method of a light emitter. It is a schematic cross-sectional view for demonstrating the exemplary manufacturing method of a light emitter. It is a schematic cross-sectional view for demonstrating the exemplary manufacturing method of a light emitter. It is a schematic cross-sectional view for demonstrating the exemplary manufacturing method of a light emitter. It is a schematic cross-sectional view for demonstrating another exemplary manufacturing method of a light emitter. It is a schematic cross-sectional view for demonstrating another exemplary manufacturing method of a light emitter. It is a schematic cross-sectional view for demonstrating another exemplary manufacturing method of a light emitter. It is a schematic cross-sectional view for demonstrating another exemplary manufacturing method of a light emitter. FIG. 3 is a schematic cross-sectional view showing another example of a light emitting body having a light emitting element 110A and a light transmitting member 140U. FIG. 3 is a schematic cross-sectional view showing another modification of the light emitting device according to an embodiment of the present disclosure. FIG. 3 is a schematic cross-sectional view showing still another modification of the light emitting device according to an embodiment of the present disclosure. It is a schematic perspective view which shows the further modification of the light emitting device by an embodiment of this disclosure. It is a figure which shows typically the cross section when the light emitting device 100E shown in FIG. 31 is cut parallel to the YZ plane in FIG. 31 at the position near the center of the light emitting device 100E. It is a top view which shows an example of the appearance when the composite substrate 400A which has the 1st conductive part 411A and the 2nd conductive part 412A is seen from the upper surface 400a side. 31 is a schematic cross-sectional view for explaining an exemplary manufacturing method of the light emitting device 100E shown in FIGS. 31 and 32. 31 is a schematic cross-sectional view for explaining an exemplary manufacturing method of the light emitting device 100E shown in FIGS. 31 and 32. 31 is a schematic cross-sectional view for explaining an exemplary manufacturing method of the light emitting device 100E shown in FIGS. 31 and 32. It is a schematic cross-sectional view for demonstrating another exemplary manufacturing method of the light emitting device by an embodiment of this disclosure. FIG. 3 is a schematic cross-sectional view showing still another modification of the light emitting device according to an embodiment of the present disclosure. FIG. 3 is a schematic plan view showing still another example of a light emitting body having a light emitting element and a light transmitting member. It is a schematic plan view which shows an example of the composite substrate which has the lead frame and the resin part integrally formed with the lead frame. It is a figure which shows typically the cross section when the light emitting structure 100Y is cut parallel to the ZX plane of the figure near the center of the light emitting structure 100Y. It is a schematic cross-sectional view for demonstrating still another exemplary manufacturing method of a light emitting device according to an embodiment of the present disclosure. It is a schematic cross-sectional view for demonstrating still another exemplary manufacturing method of a light emitting device according to an embodiment of the present disclosure. FIG. 3 is a schematic cross-sectional view showing still another modification of the light emitting device according to an embodiment of the present disclosure. It is a schematic cross-sectional view for demonstrating still another exemplary manufacturing method of a light emitting device according to an embodiment of the present disclosure. FIG. 3 is a schematic cross-sectional view showing still another modification of the light emitting device according to an embodiment of the present disclosure.

Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. The following embodiments are examples, and the method for manufacturing a light emitting device and the light emitting device according to the present disclosure are not limited to the following embodiments. For example, the numerical values, shapes, materials, steps, the order of the steps, and the like shown in the following embodiments are merely examples, and various modifications can be made as long as there is no technical contradiction.

The dimensions, shapes, etc. of the components shown in the drawings may be exaggerated for clarity and do not reflect the dimensions, shapes, and magnitude relationships between the components in actual light emitting and manufacturing equipment. There is. In addition, some elements may be omitted in order to prevent the drawings from becoming excessively complicated.

In the following description, components having substantially the same function are indicated by common reference numerals, and the description may be omitted. In the following description, terms indicating a specific direction or position (eg, "top", "bottom", "right", "left" and other terms including those terms) may be used. However, those terms use relative orientation or position in the referenced drawings for clarity only. If the relative direction or positional relationship in terms such as "top" and "bottom" in the referenced drawings is the same, it is the same as the referenced drawings in drawings other than the present disclosure, actual products, manufacturing equipment, etc. It does not have to be an arrangement. In the present disclosure, "parallel" includes the case where two straight lines, sides, surfaces, etc. are in the range of about 0 ° to ± 5 ° unless otherwise specified. Further, in the present disclosure, "vertical" or "orthogonal" includes the case where two straight lines, sides, surfaces, etc. are in the range of about 90 ° to ± 5 ° unless otherwise specified.

(Embodiment of light emitting device)
FIG. 1 shows an example of the appearance of a light emitting device according to an embodiment of the present disclosure. The light emitting device 100A illustrated in FIG. 1 has a substantially rectangular parallelepiped outer shape, and has an upper surface 100a and a lower surface 100b. For convenience of explanation, FIGS. 1 also show arrows indicating the X, Y, and Z directions orthogonal to each other. Other drawings of the present disclosure may also illustrate arrows pointing in these directions. In the example shown in FIG. 1, the side defining the rectangular shape of the upper surface 100a of the light emitting device 100A coincides with the X direction or the Y direction in the drawing.

As shown in FIG. 1, the light emitting device 100A generally includes a light emitting element 110A, a translucent member 140A that covers the light emitting element 110A, and a reflective member 150A that surrounds the light emitting element 110A and the translucent member 140A. .. The translucent member 140A has an upper surface 140a. The upper surface 140a of the translucent member 140A constitutes a part of the upper surface 100a of the light emitting device 100A.

As will be described in detail later, a plurality of first recesses are formed on the upper surface 140a of the translucent member 140A. Further, inside each first recess, a plurality of second recesses finer than the first recess are provided. The plurality of first recesses are a set of cylindrical or prismatic recesses, each having a depth of, for example, about 50 μm. These first recesses are two-dimensionally arranged on the upper surface 140a at a pitch of, for example, 2 μm or more and 20 μm or less. By forming a plurality of first recesses each including a plurality of finer second recesses on the surface of the translucent member covering the light emitting element, it is possible to obtain the effect of improving the light extraction efficiency.

FIG. 2 shows a cross section of the light emitting device 100A shown in FIG. FIG. 2 schematically shows a cross section when the light emitting device 100A is cut perpendicular to the upper surface 100a near the center of the light emitting device 100A. In the configuration exemplified in FIG. 2, the light emitting device 100A includes the wavelength conversion member 120A and the light guide member 130A in addition to the above-mentioned light emitting element 110A, the translucent member 140A, and the reflective member 150A. Hereinafter, each component of the light emitting device 100A will be described in more detail with reference to the drawings.

[Light emitting element 110A]
In the illustrated example, the light emitting element 110A has an element main body 111 having an upper surface 111a, and a positive electrode 112A and a negative electrode 114A located on the opposite side of the upper surface 111a of the element main body 111. The light emitting element 110A is, for example, an LED, and here, as the light emitting element 110A, an LED that emits blue light is exemplified.

The element body 111 includes, for example, a support substrate such as sapphire or gallium nitride, and a semiconductor laminated structure on the support substrate. The semiconductor laminated structure includes an n-type semiconductor layer and a p-type semiconductor layer, and an active layer sandwiched between these layers. The semiconductor laminated structure may include a nitride semiconductor (In _x Ally Ga _{1-xy N} , 0 ≦ x, 0 ≦ y, x + y ≦ 1) capable of emitting light in the ultraviolet to visible region. In this example, the upper surface 111a of the element main body 111 constitutes the upper surface of the light emitting element 110A.

The positive electrode 112A and the negative electrode 114A have a function as terminals for forming an electrical connection with a wiring board or the like, and supply a predetermined current to the semiconductor laminated structure. As shown in the figure, here, a part of the positive electrode 112A and the negative electrode 114A is exposed to the outside on the lower surface 100b side of the light emitting device 100A by exposing the lower surfaces thereof from the reflective member 150A.

[Wavelength conversion member 120A]
The wavelength conversion member 120A is located above the upper surface of the light emitting element 110A and has a substantially plate-like shape. The wavelength conversion member 120A is typically a member in which particles such as a phosphor are dispersed in a base material such as a resin, and absorbs at least a part of incident light to determine the wavelength of the incident light. It emits light of different wavelengths. For example, the wavelength conversion member 120A wavelength-converts a part of the blue light from the light emitting element 110A to emit yellow light. According to such a configuration, white light is obtained by mixing the blue light that has passed through the wavelength conversion member 120A and the yellow light emitted from the wavelength conversion member 120A.

There are two types of base materials for dispersing particles such as phosphors: silicone resin, modified silicone resin, epoxy resin, modified epoxy resin, urea resin, phenol resin, acrylic resin, urethane resin or fluororesin, or these resins. A resin material including the above can be used. The wavelength conversion member 120A may be provided with a light diffusion function by dispersing a material having a refractive index different from that of the base material in the material of the wavelength conversion member 120A. For example, particles such as titanium dioxide and silicon oxide may be dispersed in the base material of the wavelength conversion member 120A.

Known materials can be applied to the phosphor. Examples of the fluorescent substance are a fluoride-based fluorescent substance such as a KSF-based fluorescent substance, a nitride-based fluorescent substance such as CASN, a YAG-based fluorescent substance, a β-sialon fluorescent substance, and the like. The YAG-based phosphor is an example of a wavelength-converting substance that converts blue light into yellow light, and the KSF-based phosphor and CASN are examples of wavelength-converting substances that convert blue light into red light. Is an example of a wavelength converting substance that converts blue light into green light. The phosphor may be a quantum dot phosphor.

[Light guide member 130A]
In the configuration exemplified in FIG. 2, the light emitting element 110A is joined to the lower surface 120b of the wavelength conversion member 120A by the light-transmitting light guide member 130A. As shown in the figure, the light guide member 130A covers at least a part of the side surface 111c of the element main body 111 of the light emitting element 110A, and has an outer surface 130c which is an interface with the reflective member 150A.

By covering the side surface of the light emitting element 110A with the light guide member 130A, a part of the light emitted from the side surface 111c of the element main body 111 among the light emitted by the light emitting element 110A can be incident on the light guide member 130A. The light incident on the light guide member 130A is reflected toward the upper side of the light emitting element 110A at the position of the outer surface 130c, and is taken out to the outside of the light emitting device 100A via the wavelength conversion member 120A. Therefore, by providing the light guide member 130A, the light extraction efficiency can be improved. The light guide member 130A may cover the entire surface from the lower end to the upper end of the side surface 111c of the element main body 111. It is beneficial if the light guide member 130A covers more areas on the sides of the light emitting element 110A, as more light can be directed above the light emitting element 110A. The light guide member 130A may include a portion located between the lower surface 120b of the wavelength conversion member 120A and the upper surface of the light emitting element 110A.

As the material of the light guide member 130A, a resin material containing a transparent resin or the like as a base material can be used. A typical example of the base material of the light guide member 130A is a thermosetting resin such as an epoxy resin or a silicone resin. As the base material of the light guide member 130A, a silicone resin, a silicone-modified resin, an epoxy resin, a phenol resin, a polycarbonate resin, an acrylic resin, a polymethylpentene resin or a polynorbornene resin, or a material containing two or more of these is used. May be good.

The light guide member 130A has, for example, a transmittance of 60% or more with respect to the light having the emission peak wavelength of the light emitting element 110A. From the viewpoint of effective use of light, it is beneficial that the transmittance of the light guide member 130A at the emission peak wavelength of the light emitting element 110A is 70% or more, and it is more useful if the transmittance is 80% or more. It should be noted that the terms "translucent" and "translucent" in the present specification are construed to include and include the fact that they exhibit diffusivity with respect to incident light, and are not limited to "transparent". For example, the light guide member 130A may have a light diffusing function by dispersing a material having a refractive index different from that of the base material.

The shape of the outer surface 130c of the light guide member 130A in a cross-sectional view is not limited to the linear shape as shown in FIG. The shape of the outer surface 130c in the cross-sectional view may be a polygonal line shape, a curved shape convex in the direction approaching the light emitting element 110A, a curved shape convex in the direction away from the light emitting element 110A, or the like.

[Reflective member 150A]
The reflective member 150A is formed of a light-reflecting material such as a resin in which a light-reflecting filler is dispersed, and is covered by the outer surface 130c of the light guide member 130A and the light guide member 130A on the side surface of the light emitting element 110A. Covers unbroken areas. In the example shown in FIG. 2, the reflective member 150A also covers the side surface 120c of the wavelength conversion member 120A and the side surface 140c of the translucent member 140A.

By arranging the reflective member 150A around the light emitting element 110A, the light emitted from the side surface of the light emitting element 110A is reflected at the interface between the outer surface 130c of the light guide member 130A and the reflective member 150A, and the wavelength conversion member is used. It can lead to 120A. Therefore, the light extraction efficiency is improved. Further, in this example, the reflective member 150A also covers a region other than the region where the electrodes (that is, the positive electrode 112A and the negative electrode 114A) are arranged on the surface of the light emitting element 110A opposite to the upper surface 110a. By covering the surface opposite to the upper surface of the light emitting element 110A with the reflective member 150A except for the lower surface of the positive electrode 112A and the lower surface of the negative electrode 114A, the leakage of light to the side opposite to the upper surface of the light emitting element 110A is suppressed. Therefore, the light extraction efficiency can be improved.

As the base material of the reflective member 150A, a silicone resin, a phenol resin, an epoxy resin, a BT resin, a polyphthalamide (PPA) or the like can be used. As the light-reflecting filler, metal particles or particles of an inorganic material or an organic material having a higher refractive index than the base material can be used. Examples of light-reflecting fillers include titanium dioxide, silicon oxide, zirconium dioxide, potassium titanate, aluminum oxide, aluminum nitride, boron nitride, murite, niobium oxide, barium sulfate particles, or yttrium oxide and gadolinium oxide. Particles of various rare earth oxides and the like. In the present specification, "light reflectivity" or "reflectivity" means that the reflectance at the emission peak wavelength of the light emitting element is 60% or more. It is more beneficial when the reflectance of the reflective member 150A at the emission peak wavelength of the light emitting element 110A is 70% or more, and further useful when it is 80% or more.

[Translucent member 140A]
In the configuration exemplified in FIG. 2, the translucent member 140A has a substantially plate-like shape like the wavelength conversion member 120A, and is arranged on the upper surface 120a of the wavelength conversion member 120A. The translucent member 140A is a translucent member formed of a resin material containing a silicone resin, and typically has a transmittance of 60% or more with respect to light having an emission peak wavelength of the light emitting element 110A. Have. From the viewpoint of effective use of light, it is beneficial that the transmittance of the translucent member 140A at the emission peak wavelength of the light emitting element 110A is 70% or more, and it is more beneficial if the transmittance is 80% or more.

The silicone resin in the translucent member 140A contains an organic polysiloxane having at least one phenyl group in the molecule. Alternatively, the silicone resin in the translucent member 140A contains an organic polysiloxane having a D unit in which two methyl groups are bonded to a silicon atom. The translucent member 140A may contain both of these two types of organic polysiloxanes. The silicone resin in the translucent member 140A may contain, for example, an organic polysiloxane having a phenyl group and having a D unit. The silicone resin composition constituting the translucent member 140A may contain a modified silicone having a group other than a methyl group and a phenyl group introduced therein. The base material constituting the translucent member 140A may contain a resin other than the silicone resin.

The translucent member 140A is not limited to a member substantially made of a silicone resin, and may be a composite member containing a material other than the silicone resin. For example, the translucent member 140A may be a member or the like whose base material is a resin material containing a silicone resin and in which a light-reflecting filler is dispersed. As the light-reflecting filler, similarly to the reflective member 150A, metal particles, particles of an inorganic material or an organic material having a higher refractive index than the base material, and the like can be used. The translucent member 140A may include a wavelength conversion member such as particles of a phosphor.

As shown in FIG. 2, the upper surface 140a of the translucent member 140A has a plurality of first recesses 141. FIG. 3 schematically shows the upper surface 100a of the light emitting device 100A. Here, the plurality of first recesses 141 are arranged two-dimensionally on the upper surface 140a. In FIG. 3, for convenience of explanation, the first recess 141 is exaggerated and drawn large. In other drawings of the present disclosure, the first recess 141 may be exaggerated and enlarged for convenience of explanation.

As described above, each first recess 141 has a cylindrical shape or a prismatic shape having a bottom surface. Here, the shape of the opening of each first recess 141 located on the upper surface 140a of the translucent member 140A is circular. That is, in the configuration exemplified in FIG. 3, each of the plurality of first recesses 141 is a cylindrical recess. In the example shown in FIG. 3, the plurality of first recesses 141 are formed on the upper surface 140a of the translucent member 140A so that their centers are located on the grid points of the square lattice. The arrangement pitch of the first recess 141, that is, the distance between the centers of the two closest first recesses 141 is, for example, in the range of 2 μm or more and 20 μm or less. Of course, the arrangement of the first recess 141 and the respective shapes of the first recess 141 are not limited to the example shown in FIG. As the arrangement of the first recess 141 and the shape of the first recess 141, any arrangement and shape may be adopted. For example, the plurality of first recesses 141 may be formed on the upper surface 140a of the translucent member 140A so that their centers are located on the grid points of the triangular lattice. The contour of the opening of the first recess 141 is not limited to a smooth curve as shown in the figure, and may be zigzag.

FIG. 4 schematically shows a part of the translucent member 140A near the upper surface 140a in an enlarged manner. As schematically shown in FIG. 4, each of the plurality of first recesses 141 has a plurality of finer second recesses 142 inside thereof. In FIG. 4, the second recess 142 is exaggerated and drawn large for the sake of clarity. In the other drawings of the present disclosure, for convenience of explanation, the second
The recess 142 may be exaggerated and drawn large.

In the configuration exemplified in FIG. 4, the plurality of second recesses 142 are formed on the bottom surface 141b of each first recess 141 and the upper surface 140a of the translucent member 140A. Here, the bottom surface 141b of the first recess 141 refers to the position of the opening of the second recess 142 formed inside the first recess 141, which is shown by a broken line in FIG. In this example, a plurality of second recesses 142 are not formed on the side surface 141c of each first recess 141, but as will be described later, a plurality of second recesses 142 are formed on both the side surface 141c and the bottom surface 141b that define the first recess 141. The second recess 142 may be formed.

The arrangement pitch of the second recess 142, that is, the distance between the centers of the two second recesses 142 adjacent to each other (indicated by the double-headed arrow Pt in FIG. 4) is typically in the range of 0.1 μm or more and 1 μm or less. .. The depth of the second recess 142 (indicated by the double-headed arrow Dp in FIG. 4) is about 0.02 μm or more and 1 μm or less. In the illustrated example, the upper surface 140a of the translucent member 140A is a portion of the plurality of second recesses 142 where the opening of the second recess 142 formed in a region other than the inside of the first recess 141 is located.

FIG. 5 schematically shows an example of the shape of the second recess 142. As schematically shown in FIG. 5, the second recess 142 may be a recess having a substantially conical shape. Here, the pyramidal shape is interpreted so as to broadly include a conical shape and a prismatic shape, and therefore the shape of the opening of the second recess 142 is not limited to a circle or a regular polygon, and is an ellipse, a polygon, or an irregular shape. It may be a fixed form or the like. The size of the second recess 142 can be represented by the diameter of a circle (indicated by a dashed line in FIG. 5) that includes the opening of the second recess 142, as shown by the double-headed arrow Dm in FIG. The diameter of the circle that includes the opening of the second recess 142 is, for example, in the range of 0.05 μm or more and 0.5 μm or less.

(Exemplary manufacturing method of light emitting device)
FIG. 6 shows an outline of a method for manufacturing a light emitting device according to an embodiment of the present disclosure. The method for manufacturing the light emitting device exemplified in FIG. 6 is roughly a step of preparing a light emitting body including a light emitting element and a light transmitting member covering the light emitting element (step S11), and a light transmitting member in a heated state. A step of forming a plurality of first recesses on the upper surface of the translucent member (step S12) and a step of forming a plurality of finer second recesses after forming the plurality of first recesses (step S13). ), And a step (step S14) of irradiating the translucent member with ultraviolet rays from the upper surface side after forming the plurality of second recesses. Here, a translucent member containing a silicone resin is used as a target for pressing the mold. Hereinafter, the details of the exemplary manufacturing method of the light emitting device will be described with reference to the drawings.

First, a light emitting body including a light emitting element 110A and a light emitting member covering the light emitting element 110A is prepared (step S11 in FIG. 6). FIG. 7 shows an example in which a plurality of light emitting bodies 100U, each including a light emitting element 110A and a translucent member 140U, are temporarily fixed on a support layer 50 such as a substrate or a heat-resistant adhesive sheet. Here, for the sake of simplicity, three illuminants 100U arranged along the left-right direction of the paper surface are shown, but of course, a plurality of illuminants 100U may be arranged two-dimensionally on the support layer 50. ..

The light emitting body 100U shown in FIG. 7 has substantially the same configuration as the light emitting device 100A described with reference to FIG. 2 and the like, except that the light emitting member 140U is provided in place of the light transmitting member 140A. The illuminant 100U may be prepared by purchase or may be manufactured by the method exemplified later.

The upper surface 140a of the translucent member 140U located above the light emitting element 110A is typically a flat surface aligned with the upper surface of the reflective member 150A of the light emitting body 100U. In the illustrated example, the translucent member 140U of the light emitting body 100U is a plate-shaped member containing a silicone resin, and the silicone resin in the translucent member 140U is in a state after being already cured. The silicone resin in the translucent member 140U typically contains an organic polysiloxane having at least one phenyl group in the molecule or an organic polysiloxane having a D unit.

Next, a mold having an uneven shape on the surface is prepared. Here, as shown in FIG. 8, a mold 200 having a plurality of first convex portions 210 on one main surface 200b is used. The material of the mold 200 is not particularly limited, and for example, general materials such as hardened steel, aluminum, and beryllium copper alloy can be used.

In the configuration exemplified in FIG. 8, each of the plurality of first convex portions 210 is a cylindrical protrusion having a top surface 210a and a side surface 210c protruding from one main surface 200b of the mold 200. Here, the shape of the top surface 210a in the top view is circular. However, the shape of the top surface 210a in the top view is not limited to a perfect circle, and may be an ellipse, a distorted circle, or the like. That is, the first convex portion 210 may have a shape such as an elliptical pillar. Alternatively, the shape of each first convex portion 210 is not limited to the cylindrical shape, and may be a prismatic shape. In this case, it goes without saying that the shape of the top surface 210a in the top view is not limited to the regular polygonal shape. When the first convex portion 210 has a prismatic shape, the number of side surfaces 210c of the first convex portion 210 is 3 or more.

The height of the first convex portion 210, in other words, the distance from the main surface 200b to the top surface 210a may be in the range of, for example, 0.5 μm or more and 20 μm or less. The diameter of the top surface 210a when the first convex portion 210 has a cylindrical shape, or the diameter of the polygonal circumscribed circle which defines the outer shape of the top surface 210a when the first convex portion 210 has a prismatic shape is typical. Specifically, it is 1 μm or more and 20 μm or less. In FIG. 8, the first convex portion 210 is exaggerated and drawn large for the sake of clarity. In other drawings of the present disclosure, the first convex portion 210 may be exaggerated and enlarged for convenience of explanation.

In the configuration exemplified in FIG. 8, the first convex portion 210 is two-dimensionally arranged on the main surface 200b of the mold 200 so that the center thereof is located on the grid point of the square lattice. The arrangement pitch of the first convex portion 210, that is, the distance between the centers of the closest first convex portion 210 is, for example, in the range of 2 μm or more and 20 μm or less. Of course, the arrangement of the first convex portion 210 and the respective shapes of the first convex portion 210 are not limited to the example shown in FIG. For example, the first convex portion 210 may be two-dimensionally arranged on the main surface 200b of the mold 200 so that its center is located on the grid point of the triangular lattice.

Next, the mold 200 is pressed against the light-transmitting member 140U in a heated state, and a plurality of first recesses are formed on the upper surface 140a of the light-transmitting member 140U (step S12 in FIG. 6). Here, a plurality of light emitters 100U supported by the support layer 50 are placed on a support having sufficient rigidity together with the support layer 50, and the mold 200 is placed with the first convex portion 210 directed toward the upper surface 140a of the translucent member 140U. Facing the translucent member 140U. Further, as schematically shown by the thick arrow PS in FIG. 9, the mold 200 is pressed against the upper surface 140a of the translucent member 140U.

At this time, by pressing the mold 200 against the translucent member 140U heated to about 70 ° C. to 300 ° C. at a pressure of about 50 kPa to 50 MPa, a plurality of molds 200 are pressed against the upper surface 140a of the translucent member 140U. A plurality of first concave portions 141q corresponding to one convex portion 210 can be formed. The heating of the translucent member 140U may be performed by increasing the temperature around the translucent member 140U, or may be performed by increasing the temperature of the mold 200 and / or the support.

Since the arrangement pitch of the first convex portion 210 is in the range of 2 μm or more and 20 μm or less, the mold 20
The plurality of first recesses 141q formed on the upper surface 140a of the translucent member 140U by pressing 0 also have an arrangement pitch in the range of approximately 2 μm or more and 20 μm or less. In the example shown in FIG. 9, a single mold 200 is used to collectively form a plurality of first recesses 141q with respect to the translucent member 140U of the plurality of light emitters 100U. However, the method of the first recess 141q by pressing the mold 200 is not limited to this example, and for example, the same number of molds 200 as the light emitter 100U are used for the light transmitting member 140U of the plurality of light emitters 100U at once. A plurality of first recesses 141q may be formed.

FIG. 10 schematically shows a light emitting body 100U after the mold 200 is pulled out from the translucent member 140U. As schematically shown in FIG. 10, each of the first concave portions 141q formed in the translucent member 140U has one bottom surface 141b and one corresponding to each of the first convex portions 210 having a cylindrical shape. It has a side surface 141c. As can be understood from this, each first concave portion 141q has a shape corresponding to the shape of the first convex portion 210 provided in the mold 200. When the first convex portion 210 has, for example, a prismatic shape, each first concave portion 141q has a shape defined by one bottom surface and a plurality of side surfaces.

Here, since the top surface 210a of the first convex portion 210 having a cylindrical shape has a diameter in the range of 1 μm or more and 20 μm or less, the diameter of the circle including the opening of the first concave portion 141q is generally in the range of 1 μm or more and 20 μm or less. be. The same applies to the diameter of the circle that includes the opening of the first concave portion 141q when the first convex portion 210 has a prismatic shape.

After forming the plurality of first recesses 141q, the mold 200 is separated from the translucent member 140U. In the present embodiment, unlike the general thermal imprint method using an uncured resin material, the mold 200 is pressed against the translucent member 140U containing the cured silicone resin. Separation of the mold 200 from the translucent member 140U is relatively easy.

After forming the plurality of first recesses 141q, a plurality of finer second recesses are formed (step S13 in FIG. 6). The method of forming the plurality of second recesses is not limited to a specific method. For example, as described below, it is possible to form a plurality of second recesses inside each first recess 141q by utilizing irradiation of laser light.

FIG. 11 schematically shows the formation of a plurality of second recesses by irradiation with a laser beam. A known laser ablation device can be applied to the irradiation of the laser beam. In the example shown in FIG. 11, an example in which a laser ablation device 40 including a laser light source 430 and a galvanometer mirror 440 is applied is schematically shown. The number of galvanometer mirrors in the laser ablation apparatus 40 can be 2 or more. Examples of the laser light source 430 are Nd: YAG laser, Yb: KGB laser, Ti: sapphire laser, CO ₂ laser, excimer laser and the like.

By scanning the beam L of the laser beam from the upper surface 140a side of the translucent member 140U, a part of the translucent member 140U on the upper surface 140a side can be removed, and as a result, as schematically shown in FIG. It is possible to form a plurality of second recesses 142q in a region other than the region overlapping the first recess 141q in the upper surface 140a of the translucent member 140U and at least the bottom surface 141b of the first recess 141q. The second recess 142q can be, for example, a dimple-shaped recess having a circular shape. A galvano mirror may be used for scanning the beam L as in the example of FIG. 11, or a luminous body 100U is arranged together with the support layer 50 on a stage such as quartz glass, and the stage is moved in the XY plane. The irradiation of the laser beam may be executed while allowing the laser beam to be irradiated.

An example of the processing conditions in the formation of the fine structure pattern by the irradiation of the laser beam from the upper surface 140a side of the translucent member 140U is shown below.
Peak wavelength of laser light: 1030 nm
Laser output: 30mW
Pulse width: 260 femtoseconds Frequency: 200 kHz
Feed rate: 0.5 mm / s
Defocus from the upper surface 140a of the translucent member 140U: 0.1 μm
Spot diameter at the position of the upper surface 140a of the translucent member 140U: 0.5 μm

After forming the plurality of second recesses 142q, the translucent member 140U is irradiated with ultraviolet rays from the upper surface 140a side (step S14 in FIG. 6). Here, as schematically shown in FIG. 12, the upper surface 140a of the translucent member 140U is irradiated with ultraviolet rays by the ultraviolet irradiation device 500. The irradiation amount of ultraviolet rays at this time is, for example, 20 J / cm ² or more. The wavelength of the ultraviolet rays to be irradiated is not particularly limited, and for example, an ultraviolet irradiation device that emits ultraviolet rays having a spectrum in the wavelength range of UVA (400 to 315 nm) to UVC (280 to 140 nm) can be used. Here, a light source having a main peak wavelength of light emission of 365 nm is used.

In the embodiment of the present disclosure, after the first recess 141q and the second recess 142q are formed in the translucent member 140U, the translucent member 140U is further irradiated with ultraviolet rays. At first glance, this process of irradiating ultraviolet rays seems unnecessary. However, according to the study of the present inventor, the light emitter 100U in which the first concave portion 141q and the second concave portion 142q are formed in the translucent member 140U and is not intentionally irradiated with ultraviolet rays is heated to a high temperature of about 300 ° C. When placed in an environment, the uneven shape formed on the upper surface 140a of the translucent member 140U, particularly the shape of the first concave portion 141q, may collapse.

A light emitting device having an electrode on the bottom surface side such as the light emitting body 100U can be mounted on a wiring board or the like by, for example, reflow. Therefore, when a light emitting device that has not been intentionally irradiated with ultraviolet rays is exposed to a high temperature in a process such as reflow, the shape of the first recess 141q formed by pressing the mold 200 may be deformed. In an extreme case, the upper surface 140a of the translucent member 140U returns to a shape close to a flat surface. In other words, if the step of irradiating ultraviolet rays is omitted, a desired shape may not be obtained.

On the other hand, in the embodiment of the present disclosure, after the formation of the plurality of second recesses 142q, the upper surface 140a of the translucent member 140U is irradiated with ultraviolet rays. By executing the step of irradiating with ultraviolet rays, it becomes possible to maintain the uneven shape formed on the upper surface 140a even when the translucent member 140U is exposed to a high temperature environment of about 300 ° C. That is, according to the embodiment of the present disclosure, the translucent member 140A having the plurality of first recesses 141 and the plurality of second recesses 142 by fixing the shapes of the plurality of first recesses 141q and the plurality of second recesses 142q. Can be obtained from the translucent member 140U. Further, even when exposed to a high temperature environment of about 300 ° C., the shapes of the plurality of first recesses 141 and the plurality of second recesses 142 are unlikely to undergo a large change. Therefore, the embodiment of the present disclosure reflows. It is advantageous for the application of processes involving high temperatures such as.

By the above steps, the light emitting device 100A shown in FIG. 2 is obtained. The method of forming the plurality of second recesses 142q is not limited to surface texture ring (LST) by a laser, and for example, a plurality of second recesses 142q may be formed by spraying. Alternatively, the plurality of second recesses 142q may be formed by exposing the upper surface 140a of the translucent member 140U in which the plurality of first recesses 141q are formed to the treatment liquid.

For example, as schematically shown in FIG. 13, the treatment liquid 450 is applied or dropped onto the upper surface 140a of the translucent member 140U in which a plurality of first recesses 141q are formed. The treatment liquid 450 includes hydrofluoric acid, a mixed solution of hydrofluoric acid and hydrogen peroxide solution, a mixed solution of hydrofluoric acid and nitric acid, buffered hydrofluoric acid, and buffered hydrofluoric acid. One selected from the group consisting of a mixed solution of a hydrogen peroxide solution and a mixed solution of buffered hydrofluoric acid and nitric acid can be used. Here, the buffered hydrofluoric acid refers to a mixed solution of hydrofluoric acid and ammonium fluoride (NH _4F ) as a buffer.

Even if the surface of the translucent member 140U is treated with hydrofluoric acid or the like, a region of the upper surface 140a of the translucent member 140U that overlaps with the first recess 141q is similar to the case where laser light irradiation or spraying is applied. It is possible to form a plurality of finer second recesses 142q in regions other than the above and inside the first recess 141q. When a plurality of second recesses 142q are formed by exposing the surface of the translucent member 140U to the treatment liquid 450, the plurality of second recesses 142q are each of the second recesses 142q as enlarged and schematically shown in FIG. It can be formed not only on the bottom surface 141b of the recess 141q but also on the side surface 141c. After forming the plurality of second recesses 142q, the treatment liquid 450 is removed from the surface of the translucent member 140U using pure water.

After that, the upper surface 140a of the translucent member 140U is irradiated with ultraviolet rays in the same manner as in the example described with reference to FIG. By the above steps, the translucent member 140B having the plurality of first recesses 141 and the plurality of second recesses 142 can be formed from the translucent member 140U to obtain the light emitting device 100B shown in FIG. Compared with the above-mentioned light emitting device 100A (see FIG. 2 and the like), the light emitting device 100B has a light transmitting member 140B instead of the light transmitting member 140A. As enlarged and schematically shown in FIG. 14, in this example, the plurality of second recesses 142 are a region other than the region of the upper surface 140a of the translucent member 140B that overlaps with the first recess 141, and the first recess. In addition to the bottom surface 141b of 141, it is also formed on the side surface 141c of the first recess 141.

(Other exemplary manufacturing methods of light emitting devices)
FIG. 15 outlines a method of manufacturing a light emitting device according to another embodiment of the present disclosure. The method for manufacturing the light emitting device exemplified in FIG. 15 is roughly a step of preparing a light emitting body including a light emitting element and a light transmitting member covering the light emitting element (step S21), and a light transmitting member in a heated state. A step (step S22) of pressing a mold having a plurality of first convex portions and a plurality of second convex portions into a translucent member to form a plurality of concave portions, and after forming the plurality of concave portions, light transmission from the upper surface side. The step (step S23) of irradiating the member with ultraviolet rays is included. Hereinafter, details of other exemplary manufacturing methods of the light emitting device will be described.

First, a light emitting body 100U including a light emitting element 110A and a light emitting member covering the light emitting element 110A is prepared (step S21 in FIG. 15). This step is the same as step S11 described with reference to FIG. The point that the translucent member 140U of the light emitting body 100U contains a silicone resin is the same as the example described with reference to FIGS. 6 and 7. Therefore, here, the detailed description of the step of preparing the illuminant 100U will be omitted.

Next, a mold having an uneven shape on the surface is prepared in the same manner as in the above-mentioned example. However, here, as illustrated in FIG. 16, the mold 200A having a plurality of first convex portions 210 and a plurality of second convex portions 220 finer than the first convex portion 210 on one main surface 200b. Is used.

Similar to the mold 200 shown in FIG. 8, each of the plurality of first convex portions 210 provided on the mold 200A is, for example, a cylindrical protrusion having a top surface 210a and a side surface 210c. The point that the shape of the first convex portion 210 may be a prism shape is the same as the example described with reference to FIG.

In the configuration exemplified in FIG. 16, these plurality of first convex portions 210 are two-dimensionally arranged in a certain region Rp in the main surface 200b of the mold 200A. In this example, the plurality of first convex portions 210 are arranged so that their centers are located on the grid points of the square lattice inside the region Rp. It goes without saying that the arrangement of the first convex portions 210 is not limited to the rectangular grid pattern as in the example described with reference to FIG.

FIG. 17 shows an enlarged view of the first convex portion 210 of the mold 200A shown in FIG. 16 and its periphery thereof. As shown in FIG. 17, here, the apex surface 210a of the first convex portion 210 has a plurality of second convex portions 220 protruding from the apex surface 210a. Each of the plurality of second convex portions 220 has a cone shape such as a cone shape or a pyramid shape. In FIG. 17, the second convex portion 220 is exaggerated and drawn large for the sake of clarity. In other drawings of the present disclosure, the second convex portion 220 may be exaggerated and enlarged for convenience of explanation. The height of the cone shape of the second convex portion 220 (distance from the bottom surface to the top of the cone shape indicated by the double-headed arrow Ht in FIG. 17) is, for example, about 0.02 μm or more and 1 μm or less. The diameter of the circle that includes the bottom surface of the second convex portion 220 is, for example, in the range of 0.05 μm or more and 0.5 μm or less.

As shown in FIG. 17, in this example, the second convex portion 220 is also arranged around the first convex portion 210. The arrangement pitch of the second convex portions 220, that is, the distance between the centers of the two second convex portions 220 adjacent to each other (indicated by the double-headed arrow Pu in FIG. 17) is typically in the range of 0.1 μm or more and 1 μm or less. Is. The arrangement of the second convex portion 220 is arbitrary, and the plurality of second convex portions 220 are regularly arranged in the region Rp of the main surface 200b of the mold 200A and the top surface 210a of the first convex portion 210. It may be arranged irregularly.

After preparing the mold 200A, the plurality of first convex portions 210 and the plurality of second convex portions 220 of the mold 200A are opposed to the upper surface 140a of the translucent member 140U of the light emitting body 100U. Further, by pressing the mold 200A against the translucent member 140U in a heated state, a plurality of recesses are formed in the translucent member (step S22 in FIG. 15). Here, in the same manner as in the example described with reference to FIG. 9, as shown schematically by the thick arrow PS in FIG. 18, the upper surface 140a of the translucent member 140U in a state of being heated to about 70 ° C. to 300 ° C. Press the mold 200A against the pressure of about 50 kPa to 50 MPa.

By pressing the mold 200A, as enlarged and schematically shown in FIG. 18, a plurality of first concave portions 141q corresponding to the first convex portion 210 of the mold 200A and a plurality of second portions corresponding to the second convex portion 220. A plurality of recesses including the two recesses 142q can be collectively formed on the upper surface 140a of the translucent member 140U. In this example, corresponding to the first convex portion 210 of the mold 200A having a cylindrical shape including the top surface 210a, each of the plurality of first concave portions 141q is transparent in the form of a cylindrical concave portion having a bottom surface. It is formed on the upper surface 140a of the member 140U. Further, in this example, the second concave portion 142q has a substantially conical shape, corresponding to the second convex portion 220 of the mold 200A having a conical shape. The second recess 142q is a recess that is finer than the first recess 141q.

As described with reference to FIG. 17, here, a plurality of second convex portions 220 are provided on the top surface 210a of the first convex portion 210 of the mold 200A. Therefore, by pressing the mold 200A against the upper surface 140a of the translucent member 140U, the second recess 142q is formed at the position of the bottom surface of each first recess 141q. Further, here, in addition to the top surface 210a of the first convex portion 210, a plurality of second convex portions 220 are provided in the region around the first convex portion 210 in the main surface 200b of the mold 200A. Therefore, by pressing the mold 200A so that the plurality of second convex portions 220 reach the upper surface 140a of the translucent member 140U, the translucent member is enlarged and schematically shown in FIG. It is possible to form a plurality of second convex portions 220 in a region other than the region where the first concave portion 141q is formed in the upper surface 140a of the 140U. For example, a plurality of second recesses 142q can be formed in the region around the first recess 141q on the upper surface 140a of the translucent member 140U.

After forming a plurality of recesses including the first recess 141q and the second recess 142q, the mold 200A is separated from the light emitter 100U. In the embodiment of the present disclosure, unlike the general thermal imprint method using an uncured resin material, the mold is pressed against the translucent member 140U containing the cured silicone resin. , Separation of the mold from the translucent member 140U is relatively easy.

After that, the translucent member 140U is irradiated with ultraviolet rays from the upper surface 140a side (step S23 in FIG. 15). Irradiation of the translucent member 140U with ultraviolet rays can be performed by using, for example, an ultraviolet irradiation device 500 in the same manner as in the example described with reference to FIG. When the mold 200A is formed from a material that transmits ultraviolet rays, irradiation of ultraviolet rays may be performed through the mold 200A without separating the mold 200A from the illuminant 100U.

By irradiation with ultraviolet rays, a translucent member 140A having a plurality of first recesses 141 and a plurality of second recesses 142 can be formed from the translucent member 140U. As is easily understood from FIG. 18, in this example, the second recess 142q is not formed on the side surface 141c that defines the shape of the first recess 141q. By the above steps, the light emitting device 100A shown in FIG. 2 is obtained. As described above, by using the mold having the plurality of first convex portions 210 and the plurality of second convex portions 220, the plurality of first concave portions 141 and the plurality of second concave portions finer than the first concave portions 141 are used. 142 can be formed collectively.

According to the embodiment of the present disclosure, a fine uneven shape can be imparted to the upper surface 140a of the translucent member 140U, whereby, for example, the light extraction efficiency can be improved. Moreover, according to the embodiment of the present disclosure, it is possible to give an uneven shape to the upper surface 140a of the translucent member 140U, which is the light emitting surface of the light emitting body 100U, which can function as a light emitting device as it is. Is.

As a technique for forming a fine uneven shape, an imprint method for transferring the surface shape of a mold having fine irregularities to a layer of a resin material has been conventionally known. However, the object to which the shape is transferred by the imprint method is limited to the thermoplastic resin or the ultraviolet curable resin, and depending on the conventional method, as in the above-mentioned example, the translucent member 140U or the like is in a state after curing. It is difficult to give a fine uneven shape to the surface of the resin body after the fact. The point that the mold is pressed against the cured resin body instead of the uncured state is an unprecedented idea.

Further, in the embodiment of the present disclosure, irradiation with ultraviolet rays is performed after forming a concave portion by pressing a mold. By irradiating with ultraviolet rays, the shape formed by pressing the mold can be fixed. The point of irradiating the thermosetting resin with ultraviolet rays is also an unprecedented idea.

Irradiation with ultraviolet rays makes it possible to maintain the uneven shape formed on the upper surface 140a even when the translucent member 140U is exposed to a high temperature environment of around 300 ° C. Therefore, the present disclosure is carried out. The morphology is advantageous for the application of processes involving high temperatures, such as reflow. For example, when the light emitting device 100A is heated at a temperature of 300 ° C. for 40 minutes, the change in the depth of the first recess 141 before and after heating may be within the range of 25% or less. Here, the change in the depth of the first recess 141 is Dq, which is the average value of the depths of the first recess 141 at any 10 points before the heating is executed, and the order of the arbitrary 10 points after the heating is executed. When the average value of the depths of 1 recess 141 is Dr, it can be defined by | Dr-Dq | / Dq.

In the above-mentioned example, the first recess 141 and the second recess 142 are selectively formed on the upper surface 140a of the translucent member 140A or 140B in the upper surface 100a of the light emitting device. However, the first recess 141 and / or the second recess 142 may be formed in a region other than the upper surface 140a of the upper surface 100a of the light emitting device. For example, when the base material of the reflective member 150A contains a silicone resin, the first convex portion 210 and the second convex portion 220 of the mold are arranged at positions facing the upper surface of the reflective member 150A. It is possible to form the first recess 141 and the second recess 142 on the upper surface of the reflective member 150A.

Hereinafter, an exemplary manufacturing method of the illuminant 100U will be described with reference to the drawings. First, a light emitting element 110A having an upper surface and having a positive electrode 112A and a negative electrode 114A on the lower surface side located on the opposite side of the upper surface is prepared. The light emitting element 110A may be prepared by purchase.

Next, as shown in FIG. 19, a support 60 such as a substrate or a heat-resistant adhesive sheet is prepared, and the positive electrode 112A and the negative electrode 114A are directed toward the upper surface 60a of the support 60, and the light emitting element 110A is placed on the support 60. Deploy. Next, as shown in FIG. 20, the first resin material 130r containing a transparent resin or the like as a base material is applied to the upper surface 111a, which is the upper surface of the light emitting element 110A, by a dispenser or the like.

Next, as schematically shown in FIG. 21, the wavelength conversion member 120A and the translucent member 140U are arranged on the first resin material 130r, and the first resin material 130r is cured. In this example, a laminated sheet LB including a wavelength conversion member 120A and a translucent member 140U is prepared, and the wavelength conversion member 120A and the translucent member 140U are collectively arranged on the first resin material 130r. For the laminated sheet LB, for example, a fluorescent material sheet in which the resin in the resin material in which the fluorescent material particles are dispersed is in a B stage state, and a translucent resin sheet formed from a silicone resin raw material are prepared. These can be prepared by bonding them together by heat and obtaining a cut piece having a predetermined size by an ultrasonic cutter or the like. After arranging the laminated sheet LB, the light guide member 130A can be formed from the first resin material 130r by curing the first resin material 130r.

Next, as shown in FIG. 22, the structure on the support 60 is covered with the light-reflecting resin layer 150T. The light-reflecting resin layer 150T can be formed, for example, by applying a second resin material in which a light-reflective filler is dispersed to the upper surface 60a of the support 60 and then curing the second resin material. For example, transfer molding can be applied to the formation of the light-reflecting resin layer 150T. In the state shown in FIG. 22, the upper surface 140a and the side surface 140c of the translucent member 140U are covered with the light-reflecting resin layer 150T.

Next, the upper surface 140a of the translucent member 140U is exposed from the ground surface by removing a part of the light-reflecting resin layer 150T from the upper surface side of the light-reflecting resin layer 150T by applying a grinding process or the like. Further, the structure on the support 60 is cut out into a desired shape by a dicing device or the like. For example, the light-reflecting resin layer 150T after grinding is cut at the positions of two light emitting elements 110A adjacent to each other. By the steps of grinding and cutting the light-reflecting resin layer 150T, the reflective member 150A is formed from the light-reflective resin layer 150T, and as shown in FIG. 23, a light emitting body 100U is obtained on the support 60.

Conventionally, in a manufacturing method in which a light-transmitting member is embedded inside a light-reflecting resin layer, it has been difficult to post-externally impart an uneven pattern to the upper surface of the light-transmitting member that appears on the ground surface. On the other hand, according to the embodiment of the present disclosure, it is possible to impart a shape to the surface of the translucent member 140U after curing. Therefore, after obtaining a light emitting body that can be used as a product, it becomes possible to give a shape to a member located in front of the light emitting element such as a light transmitting member 140U after the fact, and light is taken out from the light emitting device. The effect of improving efficiency can be expected.

The method for producing the illuminant is not limited to the examples described with reference to FIGS. 19 to 23, and for example, the following production methods can also be applied. First, as shown in FIG. 24, a first resin layer 170 having a translucent portion 172 is prepared. The resin layer 170 may have two or more translucent portions 172. In the configuration exemplified in FIG. 24, the resin layer 170 has a light-reflecting resin portion 174, and the light-transmitting portions 172 are separated from each other by the light-reflecting resin portion 174. In this example, each translucent unit 172 includes a translucent layer 140L and a wavelength conversion layer 120L.

The resin layer 170 can be obtained, for example, as follows. First, a light-reflecting resin sheet is prepared. The light-reflecting resin sheet may be a resin sheet in which particles of titanium dioxide and silicon oxide are dispersed in a silicone resin in an amount of about 60% by weight. For the formation of the light-reflecting resin sheet, compression molding, transfer molding or injection molding, or molding to which a printing method or a spray method is applied can be used.

Next, a through hole is provided in the resin sheet by punching or the like. The shape of the through hole in the top view is, for example, a rectangular shape. After the through hole is formed, the inside of the through hole is filled with a third resin material containing a silicone resin as a base material and having phosphor particles dispersed in the base material by a potting method, a printing method, a spray method, or the like. At this time, the particles of the phosphor are settled in the third resin material filled in the through hole to cure the third resin material, thereby forming a translucent portion having a difference in the concentration of the phosphor in the thickness direction. It is possible to do. For example, it is possible to form a translucent portion in which a large amount of phosphor particles are distributed on the lower surface side. Alternatively, a transparent resin material may be placed inside the through hole and cured, and then a third resin material may be applied onto the transparent resin material to fill the through hole with these materials.

When the particles of the phosphor are settled and turned upside down after the third resin material is cured, a resin layer 170 having a light-reflecting resin portion 174 and a plurality of translucent portions 172 as shown in FIG. 24 can be obtained. .. In the configuration exemplified in FIG. 24, the translucent layer 140L is a layer in which the concentration of the particles of the phosphor is relatively low in the translucent portion 172. In FIG. 24, these layers are illustrated as if there is a boundary between the wavelength conversion layer 120L and the translucent layer 140L, but the boundary between these layers cannot be clearly recognized. There is also.

Next, the first resin material 130r is applied to the region of the resin layer 170 in which the translucent portion 172 is arranged by a dispenser or the like. Further, as shown in FIG. 25, the light emitting element 110A is arranged on the first resin material 130r with the positive electrode 112A and the negative electrode 114A facing opposite to the resin layer 170. By curing the first resin material 130r, the light guide member 130A covering at least a part of the side surface 111c of the element main body 111 can be formed from the first resin material 130r.

Next, as shown in FIG. 26, a light-reflecting resin layer 150T as a second resin layer covering the structure on the resin layer 170 is formed. As the material of the light-reflecting resin layer, the above-mentioned second resin material can be used. For example, transfer molding can be applied to the formation of the light-reflecting resin layer 150T.

Next, by applying grinding or the like to remove a part of the light-reflecting resin layer 150T from the upper surface side of the light-reflecting resin layer 150T, the positive electrode 112A and the negative electrode 114A of each light emitting element 110A are exposed from the ground surface. .. Further, the resin layer 170 and the light-reflecting resin layer 150T are cut at the positions of the two light emitting elements 110A adjacent to each other by a dicing device or the like. By cutting the resin layer 170 and the light-reflecting resin layer 150T, the reflective member 150A is formed from the light-reflective resin portion 174 and the light-reflective resin layer 150T, and as shown in FIG. 27, the same as the example of FIG. 23. Luminous body 100U can be obtained. In this example, the translucent layer 140L and the wavelength conversion layer 120L of the translucent portion 172 of the resin layer 170 correspond to the translucent member 140U and the wavelength conversion member 120A of the light emitter 100U, respectively.

The light-reflecting resin layer 150T and the resin layer 170 may be cut at positions overlapping the light-transmitting portion 172 in the step of individualizing a plurality of structures, each of which has a light emitting element 110A. Alternatively, the process described with reference to FIGS. 26 and 27 by arranging a plurality of light emitting elements 110A in a laminated sheet including the wavelength conversion member 120A and the translucent member 140U instead of the resin layer 170 shown in FIG. 24. You may do it. In these cases, as schematically shown in FIG. 28, a light emitting body 100T in which the side surface 140c of the translucent member 140U and the side surface 120c of the wavelength conversion member 120A are exposed from the reflective member 150A can be obtained.

If the steps S12 to S14 of FIG. 6 or the steps S22 and S23 of FIG. 15 are applied to the light emitting body 100T instead of the above-mentioned light emitting body 100U, for example, the light emitting device 100C shown in FIG. 29 can be obtained. .. Comparing the light emitting device 100C shown in FIG. 29 with the light emitting device 100A shown in FIG. 2, in the light emitting device 100C, the side surface 140c of the translucent member 140A and the side surface 120c of the wavelength conversion member 120A are exposed from the reflective member 150A. There is. As described with reference to FIGS. 8 to 13, a plurality of first recesses 141q are formed on the upper surface 140a of the translucent member 140U by pressing the mold 200 against the transmissive member 140U in a heated state, and further. By exposing the upper surface 140a of the translucent member 140U to the treatment liquid, a plurality of second recesses 142q finer than the first recess 141q may be formed. Also in this case, the point that the translucent member 140U is irradiated with ultraviolet rays from the upper surface 140a side after the formation of the plurality of first recesses 141q is the same as in each of the above examples. By adopting such a process, the light emitting device 100D shown in FIG. 30 can be obtained. The light emitting device 100D has substantially the same configuration as the light emitting device 100B shown in FIG. 14, except that the side surface 140c of the translucent member 140B and the side surface 120c of the wavelength conversion member 120A are exposed from the reflective member 150A.

FIG. 31 shows another example of the appearance of the light emitting device. The light emitting device 100E shown in FIG. 31 includes a light emitting element (not shown in FIG. 31), a translucent member 140C arranged on the front surface of the light emitting element, a reflective member 150B covering the side surface of the translucent member 140C, and a composite substrate. Including 400B. The composite substrate 400B includes a substrate 410B, a first conductive portion 411B, and a second conductive portion 412B. In the configuration exemplified in FIG. 31, the reflective member 150B reaches the composite substrate 400B and covers a part of the first conductive portion 411B and a part of the second conductive portion 412B.

FIG. 32 schematically shows a cross section when the light emitting device 100E is cut in parallel with the YZ plane in FIG. 31 at a position near the center of the light emitting device 100E. As shown in FIG. 32, the first conductive portion 411B and the second conductive portion 412B are electrically connected to the positive electrode 112A and the negative electrode 114A of the light emitting element 110A by the joining member 420, respectively. In the configurations exemplified in FIGS. 31 and 32, the light emitting device 100E has a shape long in the Y direction with respect to the X direction in the figure, and is used as a so-called side view type light emitting device.

The translucent member 140C of the light emitting device 100E has a plurality of first recesses 141 on the upper surface 140a thereof, similarly to the translucent members 140A and 140B described above. Each first recess 141 has a bottom surface 141b and one or more side surfaces 141c, and has a plurality of second recesses 142 at least in the bottom surface 141b, as shown enlarged in FIG. The translucent member 140C of the light emitting device 100E has substantially the same configuration as the translucent member 140A of the light emitting device 100A described above, except that it has a long plan view shape that is long in the Y direction with respect to the X direction in the figure. Have. Similar to the above-mentioned translucent member 140B, a plurality of second recesses 142 may be formed on the side surface 141c of each first recess 141 of the translucent member 140C.

For example, in the light emitting body manufacturing process described with reference to FIGS. 19 to 23, the light emitting device 100E efficiently uses the composite substrate 400A as illustrated in FIG. 33 instead of the support 60. Can be manufactured. FIG. 33 shows an example of the appearance of the composite substrate 400A when viewed from the upper surface 400a side thereof. As shown in FIG. 33, the composite substrate 400A has a substrate 410A and a first conductive portion 411A and a second conductive portion 412A provided on the substrate 410A. The substrate 410A has a through hole 414. Although not shown in FIG. 33, a part of the first conductive portion 411A and a part of the second conductive portion 412A extend to the lower surface opposite to the upper surface 400a through the through hole 414.

When the composite substrate 400A is used, instead of temporarily fixing the plurality of light emitting elements 110A to the support 60 (see FIG. 19), for example, the plurality of light emitting elements 110A are connected to the upper surface 400a of the composite substrate 400A by flip chip connection. Is fixed to. At this time, the positive electrode 112A and the negative electrode 114A of each light emitting element 110A are connected to the first conductive portion 411A and the second conductive portion 412A of the composite substrate 400A by a joining member such as solder. The rectangle drawn with a thin broken line in FIG. 33 indicates the position where the light emitting element 110A is arranged.

After forming the light guide member 130A and arranging the wavelength conversion member 120A and the translucent member 140U, the structure on the upper surface 400a of the composite substrate 400A is formed of a light reflective resin in the same manner as in the process described with reference to FIG. Cover with layer 150T. After the light-reflecting resin layer 150T is formed, the upper surface 140a of the light-transmitting member 140U is exposed from the light-reflective resin layer 150T by grinding or the like. By the above steps, a light emitting body having a plurality of light emitting elements 110A, a translucent member 140U, and a composite substrate 400A can be obtained.

Further, for example, in the same manner as in the example described with reference to FIG. 9, as shown in FIG. 34, the mold 200 is pressed against the upper surface 140a of the translucent member 140U in a heated state to obtain the translucent member 140U. A plurality of first recesses 141q are formed on the upper surface 140a. FIG. 34 schematically shows cross sections of three units, each containing a light emitting element 110A, in order to avoid overcomplexing the drawings.

After separating the mold 200 from the translucent member 140U, a plurality of finer second recesses are formed. For example, as schematically shown in FIG. 35, in the same manner as in the example described with reference to FIG. 11, among the bottom surface 141b of each first recess 141q and the top surface 140a of the translucent member 140U by irradiation with laser light. A plurality of second recesses 142q are formed in a region other than the region overlapping the first recess 141q. Instead of irradiating the laser beam, a mold 200A (see FIGS. 16 and 17) having a plurality of first convex portions 210 and a plurality of second convex portions 220 is used to use a plurality of first concave portions 141q and a plurality of second concave portions. 142q and 142q may be formed together.

Further, as schematically shown in FIG. 36, the translucent member 140U is irradiated with ultraviolet rays from the upper surface 140a side of the translucent member 140U in the same manner as in the example described with reference to FIG. By irradiation with ultraviolet rays, a translucent member 140C having a plurality of first recesses 141 and a plurality of second recesses 142 can be obtained from the translucent member 140U. After that, the composite substrate 400B shown in FIG. 32 is obtained by cutting the composite substrate 400A and the light-reflecting resin layer 150T together as needed by a dicing device or the like at the position shown by the thick broken line CT in FIG. A light emitting device 100E included in a part can be obtained. The substrate 410B, the first conductive portion 411B, and the second conductive portion 412B shown in FIGS. 31 and 32 are a part of the substrate 410A, the first conductive portion 411A, and the second conductive portion 412A shown in FIG. 33, respectively.

Instead of irradiating the laser beam, as schematically shown in FIG. 37, the upper surface 140a of the translucent member 140U in which the plurality of first recesses 141q are formed is exposed to the treatment liquid 450 to form the plurality of second recesses 142q. It may be formed. The point that the translucent member 140U is irradiated with ultraviolet rays from the upper surface 140a side of the translucent member 140U after the formation of the plurality of second recesses 142q is the same as in each of the above examples. According to such a step, the translucent member 140D having a plurality of second recesses 142 formed not only on the bottom surface 141b of each first recess 141 but also on the side surface 141c as shown in FIG. 38 is provided. A light emitting device 100F having a composite substrate 400B can be obtained.

FIG. 39 shows yet another example of a light emitter having a light emitting element and a translucent member. Instead of the above-mentioned illuminant 100U or illuminant 100T, steps S12 to S14 shown in FIG. 6 or steps S22 and S23 shown in FIG. 15 may be applied to the illuminant 100S shown in FIG. 39.

In the configuration exemplified in FIG. 39, each of the light emitting bodies 100S has a two-dimensional repeating structure having a light emitting structure 100Y including a light emitting element 110B and a translucent member 340Z as a unit. The translucent member 340Z contains a silicone resin in the same manner as the translucent members 140A to 140D described above. That is, the silicone resin in the translucent member 340Z typically has an organic polysiloxane having at least one phenyl group in the molecule and / or an organic having a D unit in which two methyl groups are bonded to a silicon atom. Contains polysiloxane. In FIG. 39, four of the plurality of light emitting structures 100Y are taken out and shown.

Each light emitting structure 100Y further has a resin portion 350F provided with a recess 350e, and a pair of conductive leads 361 and 362. The light emitting element 110B is located inside the recess 350e of each light emitting structure 100Y, and the translucent member 340Z covers the light emitting element 110B inside the recess 350e. The upper surface of the conductive lead 361 and the upper surface of the conductive lead 362, and the surface of a part of the resin portion 350F that spatially and electrically separates them from each other form the bottom surface of the recess 350e. In this example, the light emitting element 110B is fixed on the upper surface of the conductive lead 361 of the conductive lead 361 and the conductive lead 362. As schematically shown in FIG. 39, the light emitting element 110B has a positive electrode 112B and a negative electrode 114B on the upper surface side thereof, and here, the positive electrode 112B is electrically attached to the conductive lead 362 by the conductive wire 372. Connected, the negative electrode 114B is electrically connected to the conductive lead 361 by a conductive wire 371.

The illuminant 100S can be manufactured, for example, as follows. First, a composite substrate including a conductive lead frame and a resin portion 350F provided with a plurality of recesses 350e is prepared. The composite substrate 300F illustrated in FIG. 40 has a plurality of sets of conductive leads 361 and 362, and a plurality of connecting portions 363 arranged between adjacent sets and connecting these sets to each other. Includes lead frame 360F. The lead frame 360F may have, for example, a base material formed of Cu and a metal layer covering the base material. The metal layer covering the base material is, for example, a plating layer containing Ag, Al, Ni, Pd, Rh, Au, Cu, or an alloy thereof.

As shown in the figure, a part of the conductive lead 361 and a part of the conductive lead 362 are exposed at the bottom of each of the recesses 350e of the resin portion 350F. Each of the pair of conductive leads 361 and 362 facing each other in the recess 350e has a gap Gp formed by spatially separating the conductive leads 361 and 362 from each other. The gap Gp is filled with the material constituting the resin portion 350F. The composite substrate 300F can be obtained by integrally forming the resin portion 350F on the lead frame 360F by transfer molding or the like. For example, the lead frame 360F can be obtained by arranging the lead frame 360F in the cavity of the mold, filling the inside of the cavity with a resin material in which a light-reflecting filler is dispersed, and curing the resin material. .. As the material of the resin portion 350F, the same materials as those of the above-mentioned reflective members 150A and 150B can be applied.

After obtaining the composite substrate 300F, the light emitting element 110B is bonded onto the conductive lead 361 with an insulating material such as a resin material such as an epoxy resin or a silicone resin, or a conductive material such as Ag paste. Further, the positive electrode 112B of the light emitting element 110B and the conductive lead 362 are electrically connected by the conductive wire 372, and the negative electrode 114B and the conductive lead 361 are electrically connected by the conductive wire 371.

After arranging the light emitting element 110B in the recess 350e of the resin portion 350F, each recess 350e is filled with a silicone resin material containing an uncured silicone resin, and the silicone resin material is cured to cover the light emitting element 110B. Form the member 340Z. As the material of the translucent member 340Z, the same resin material as the material for forming the translucent members 140A to 140D described above can be applied. By the above steps, the illuminant 100S shown in FIG. 39 is obtained.

Here, a plurality of first recesses and a plurality of second recesses finer than the first recess are further formed on the upper surface of the translucent member 340Z. The formation of the plurality of first recesses and the plurality of second recesses may be generally performed according to the same steps as steps S12 to S14 shown in FIG. 6 or the same steps as steps S22 and S23 shown in FIG. ..

For example, the main surface 200b of the mold 200 provided with the first convex portion 210 is opposed to the upper surface 340a of the translucent member 340Z, and the mold 200 is pressed against the translucent member 340Z in a state where the translucent member 340Z is heated. FIG. 41 schematically shows a cross section of one of the light emitting structures 100Y constituting the light emitting body 100S taken out. In this example, the upper surface 340a of the translucent member 340Z is aligned with the upper surface 350a of the resin portion 350F, and the upper surface 340a of the translucent member 340Z constitutes the upper surface of the light emitting structure 100Y together with the upper surface 350a of the resin portion 350F. There is.

By pressing the mold 200, as shown schematically in FIG. 41, it is possible to form a plurality of first recesses 341q on the upper surface 340a of the translucent member 340Z. Here, although a plurality of first recesses 341q are selectively formed on the upper surface 340a of the translucent member 340Z, the plurality of first recesses are formed on the entire upper surface of the light emitting structure 100Y including the upper surface 350a of the resin portion 350F. The concave portion 341q may be formed.

After the mold 200 is separated, as schematically shown in FIG. 42, for example, the bottom surface 341b of each first recess 341q and the upper surface 340a of the translucent member 340Z other than the region overlapping the first recess 341q by irradiation with a laser beam. A plurality of finer second recesses 342q are formed in the region. Needless to say, instead of irradiating the laser beam, a plurality of first recesses 341q and a plurality of second recesses 342q may be collectively formed by using a mold 200A or the like.

Next, as schematically shown in FIG. 43, the translucent member 340Z is irradiated with ultraviolet rays from the upper surface 340a side of the translucent member 340Z in the same manner as in the example described with reference to FIG. By irradiating with ultraviolet rays, it is possible to fix the shapes of the plurality of first recesses 341q and the shapes of the plurality of second recesses 342q, so to speak. Thereby, the translucent member 340E having the plurality of first recesses 341 and the plurality of second recesses 342 can be formed from the translucent member 340Z. After that, the light emitting device 100G shown in FIG. 44 is obtained by individualizing the light emitting body 100S with the light emitting structure 100Y as a unit by a dicing device or the like.

The light emitting device 100G has a reflective member 350 having a recess 350e. The reflective member 350 is formed by cutting the resin portion 350F described above in the step of individualizing. By the step of individualization, most of the connecting portion 363 (see FIG. 40) of the lead frame 360F is removed. In this example, the side surface 341c of each first recess 341 basically does not have a second recess 342.

Instead of irradiating the laser beam, as schematically shown in FIG. 45, the plurality of second recesses 342q are exposed to the treatment liquid 450 on the upper surface 340a of the translucent member 340Z in which the plurality of first recesses 341q are formed. It may be formed. After forming the plurality of second recesses 342q, the translucent member 340Z is irradiated with ultraviolet rays from the upper surface 340a side of the translucent member 340Z in the same manner as in the example described with reference to FIG. 43. According to such a step, the light emitting device 100H shown in FIG. 46 can be obtained.

The main difference between the light emitting device 100H shown in FIG. 46 and the light emitting device 100G shown in FIG. 44 is that the light emitting device 100H has a light transmitting member 340F instead of the light transmitting member 340E. As enlarged and schematically shown in FIG. 46, each first recess 341 provided in the translucent member 340F has a plurality of second recesses 342 not only on the bottom surface 341b but also on the side surface 341c thereof.

The translucent member 340E of the light emitting device 100G and the translucent member 340F of the light emitting device 100H may have a function of light diffusion by dispersing particles such as titanium dioxide and silicon oxide in the base material. Further, the translucent member 340E of the light emitting device 100G and the translucent member 340F of the light emitting device 100H may contain particles such as a phosphor. The particles such as the phosphor may be dispersed substantially uniformly in the base material of the translucent member, or may have a concentration bias in the Z direction in the figure, for example.

According to the embodiment of the present disclosure, it is possible to form an uneven pattern on the surface of the thermosetting resin after curing, which is advantageous for improving the efficiency of light extraction. The light emitting device according to the embodiment of the present disclosure can be widely used as a light source of various lighting devices, a strobe light source such as a camera, a light source for a backlight unit of a liquid crystal display device, and the like.

40 Laser ablation device 100A-100H Luminous device 100S-100U Luminous body 100Y Luminous structure 110A, 100B Luminous element 120A Frequency conversion member 130A Light guide member 140, 140A-140D, 140U Translucent member 140a Top surface of translucent member 141 Translucent member 1st concave part 142 2nd concave part of translucent member 150A, 150B Reflective member 200, 200A type 210 type 1st convex part 220 type 2nd convex part 300F Composite substrate 340Z, 340E, 340F Translucent member 340a Translucent member Top surface of member 341 First recess of translucent member 342 Second recess of translucent member 350 Reflective member 350F Resin part of composite substrate 360F Lead frame of composite substrate 361, 362 Conductive leads 400A, 400B Composite substrate 410A, 410B Substrate 411A, 411B 1st conductive part 412A, 412B 2nd conductive part 450 Treatment liquid 500 Ultraviolet irradiation device

Claims (23)

A step of preparing a light-emitting body including a light-emitting element and a light-transmitting member that covers the light-emitting element and has an upper surface, wherein the light-transmitting member contains a silicone resin.
The plurality of first convex portions of the mold having the plurality of first convex portions are opposed to the upper surface of the translucent member, and the mold is pressed against the upper surface of the transmissive member in a heated state, respectively. In the step (B) of forming a plurality of first recesses having a bottom surface on the upper surface thereof,
After the step (B), a plurality of finer second recesses are formed in a region other than the plurality of first recesses in the upper surface of the translucent member and at least in the bottom surface of the plurality of first recesses. Process (C) and
A method for manufacturing a light emitting device, comprising the step (D) of irradiating the translucent member with ultraviolet rays from the upper surface side after the step (C). The manufacturing of the light emitting device according to claim 1, wherein the step (C) includes a step (C1) of forming the plurality of second recesses by irradiating the translucent member with a laser beam from the upper surface side. Method. In the step (C), the surface of the translucent member is surfaced with hydrofluoric acid, a mixed solution of hydrofluoric acid and hydrogen peroxide solution, a mixed solution of hydrofluoric acid and nitric acid, and buffered hydrofluoric acid. By treating with one selected from the group consisting of a mixed solution of buffered hydrofluoric acid and hydrogen peroxide solution, and a mixed solution of buffered hydrofluoric acid and nitric acid, the above-mentioned second plurality of second. The method for manufacturing a light emitting device according to claim 1, further comprising a step (C2) of forming a recess. A step of preparing a light-emitting body including a light-emitting element and a light-transmitting member that covers the light-emitting element and has an upper surface, wherein the light-transmitting member contains a silicone resin.
The plurality of first convex portions and the plurality of second convex portions of a mold having a plurality of first convex portions and a plurality of second convex portions finer than the first convex portions are formed on the upper surface of the translucent member. A step (B) of forming a plurality of recesses in the translucent member by pressing the mold against the upper surface of the translucent member in a heated state so as to face each other.
The step (B) includes a step (C) of irradiating the translucent member with ultraviolet rays from the upper surface side.
The plurality of recesses
A plurality of first recesses, each having a bottom surface,
Includes a plurality of second recesses that are finer than the plurality of first recesses.
In the step (B), the plurality of second recesses are formed in a region other than the region where the plurality of first recesses are provided in the upper surface of the translucent member and the bottom surface of the plurality of first recesses. A method for manufacturing a light emitting device. The second convex portion of the mold has a cone shape with a height of 0.02 μm or more and 1 μm or less.
The method for manufacturing a light emitting device according to claim 4, wherein the diameter of the circle including the bottom surface of the second convex portion is 0.05 μm or more and 0.5 μm or less. The method for manufacturing a light emitting device according to claim 4 or 5, wherein the arrangement pitch of the second convex portion of the mold is 0.1 μm or more and 1 μm or less. The method for manufacturing a light emitting device according to any one of claims 1 to 6, wherein the plurality of first recesses have a cylindrical shape or a prismatic shape including the bottom surface and one or more side surfaces defining the first recess. 7. The diameter of the circle including the opening of the first recess is 1 μm or more and 20 μm or less.
The method for manufacturing a light emitting device according to the above. The method for manufacturing a light emitting device according to any one of claims 1 to 8, wherein the arrangement pitch of the first recess is 2 μm or more and 20 μm or less. The light emitting device according to any one of claims 1 to 9, wherein the plurality of first convex portions of the mold have a cylindrical shape or a prismatic shape including a top surface and one or more side surfaces defining the first convex portion. Manufacturing method. The diameter of the top surface of the cylinder shape of the first convex portion or the diameter of the circle circumscribing the top surface of the prism shape is 1 μm or more and 20 μm or less, and the diameter of the cylinder shape or the prism shape of the first convex portion. The method for manufacturing a light emitting device according to claim 10, wherein the height is 0.5 μm or more and 20 μm or less. The method for manufacturing a light emitting device according to any one of claims 1 to 11, wherein the arrangement pitch of the first convex portion of the mold is 2 μm or more and 20 μm or less. The second recess has a cone shape with a depth of 0.02 μm or more and 1 μm or less.
The method for manufacturing a light emitting device according to any one of claims 1 to 12, wherein the diameter of the circle including the opening of the second recess is 0.05 μm or more and 0.5 μm or less. The method for manufacturing a light emitting device according to any one of claims 1 to 13, wherein the arrangement pitch of the second recess is 0.1 μm or more and 1 μm or less. The method for manufacturing a light emitting device according to any one of claims 1 to 14, wherein the irradiation amount of ultraviolet rays in the step (C) is 20 J / cm ² or more. Light emitting element and
It has an upper surface and is provided with a translucent member that covers the light emitting element.
The upper surface of the translucent member has a plurality of first recesses, each having a bottom surface and one or more side surfaces.
Each first recess is a light emitting device having a plurality of second recesses finer than the first recess on the bottom surface and one or more side surfaces thereof. The light emitting device according to claim 16, wherein the plurality of first recesses have a cylindrical shape or a prismatic shape including the bottom surface and one or more side surfaces defining the first recess. The light emitting device according to claim 17, wherein the diameter of the circle including the opening of the first recess is 1 μm or more and 20 μm or less. The light emitting device according to any one of claims 16 to 18, wherein the arrangement pitch of the first recess is 2 μm or more and 20 μm or less. The second recess has a cone shape with a depth of 0.02 μm or more and 1 μm or less.
The light emitting device according to any one of claims 16 to 19, wherein the diameter of the circle including the opening of the second recess is 0.05 μm or more and 0.5 μm or less. The light emitting device according to any one of claims 16 to 20, wherein the arrangement pitch of the second recess is 0.1 μm or more and 1 μm or less. The translucent member contains a silicone resin and contains
The light emitting device according to any one of claims 16 to 21, wherein the silicone resin contains an organic polysiloxane having at least one phenyl group in the molecule. The translucent member contains a silicone resin and contains
The light emitting device according to any one of claims 16 to 22, wherein the silicone resin contains an organic polysiloxane having a D unit in which two methyl groups are bonded to a silicon atom.

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