JP2020129677A - Method for manufacturing light emitting device, and light emitting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a novel method for imparting a fine uneven shape.
A method of manufacturing a light emitting device includes a step (a) of preparing a light emitting body having a light emitting element having an upper surface and a translucent resin body covering at least the upper surface of the light emitting element, and a pattern of unevenness on the surface. And a step (b) of forming a translucent member that covers at least the upper surface of the light-emitting element, the step (b) including a plurality of convex portions of a mold having a plurality of convex portions on the surface of the resin body. A step (b1) of forming a plurality of concave portions on the surface by pressing a mold against the surface of the resin body in a state of being opposed to each other, and a step of irradiating the surface of the resin body with ultraviolet rays after the step (b1) (B2) is included.
[Selection diagram] Figure 1

Description

The present disclosure relates to a method of forming a translucent member and a method of manufacturing a light emitting device. The present disclosure also relates to a light emitting device.

As a technique for forming fine unevenness, an imprint method is known in which the surface shape of a mold having fine unevenness is transferred to a layer of resin material. The object whose shape is transferred by the imprint method is a thermoplastic resin or an ultraviolet curable resin. In the former case, the mold is pressed against the thermoplastic resin, the thermoplastic resin is cured by heating, and then the mold is separated from the thermoplastic resin. In the latter case, a mold that transmits ultraviolet rays is pressed against the ultraviolet curable resin, the ultraviolet curable resin is cured by irradiation of ultraviolet rays through the mold, and then the mold is separated from the ultraviolet curable resin.

The imprint method is used, for example, for forming an antireflection film for a display device, as disclosed in Patent Document 1 below. Alternatively, the imprint method can be used for manufacturing a polarizing film and the like. The imprint method may also be applied to the formation of a resist pattern used for etching. In Patent Document 2 below, the imprint method can be applied to the formation of a mask for forming a frustum-shaped or pyramidal-shaped pattern on the surface of a semiconductor laminated portion including an n-type semiconductor layer and a p-type semiconductor layer. Explained that there is. As described above, the imprint method is also expected to be applied to a light emitting element represented by a light emitting diode (LED), an uneven shape for improving light extraction efficiency in an organic EL light emitting device and the like.

JP, 2017-032806, A JP, 2016-001639, A

According to the imprint method, it is possible to form a fine uneven shape. However, the object to which the shape can be applied is currently limited to either an uncured thermoplastic resin or an ultraviolet curable resin.

A method of forming a translucent member according to an embodiment of the present disclosure has a main surface, and the plurality of convex portions of a mold having a plurality of convex portions on the main surface of a cured resin body containing a silicone resin. Facing each other and pressing the die against the main surface of the resin body in a heated state to form a plurality of recesses on the main surface (A), and the resin after the step (A). Irradiating the main surface of the body with ultraviolet light (B).

A method of manufacturing a light emitting device according to another embodiment of the present disclosure includes a step of preparing a light emitting body having a light emitting element having an upper surface and a translucent resin body that covers at least the upper surface of the light emitting element (a). And a step (b) of forming a translucent member having a pattern of concavities and convexities on the surface and covering at least the upper surface of the light emitting element, the step (b) including a mold having a plurality of convex portions. A step (b1) of forming a plurality of concave portions on the surface by causing the plurality of convex portions to face the surface of the resin body and pressing the mold against the surface of the resin body in a heated state; After the step (b1), a step (b2) of irradiating the surface of the resin body with ultraviolet rays is included.

A method for manufacturing a light emitting device according to another embodiment of the present disclosure includes a step (a) of preparing a light emitting element having an upper surface and a positive electrode and a negative electrode provided on the side opposite to the upper surface, and the surface having unevenness. And a step (b) of forming a translucent member having at least the above pattern and covering at least the upper surface of the light emitting element, the step (b) being formed by curing an uncured silicone resin raw material. On the surface of the translucent resin body, the plurality of convex portions of a mold having a plurality of convex portions are opposed to each other, and the mold is pressed against the surface of the resin body in a heated state, thereby making the surface The method includes a step (b1) of forming a plurality of recesses and a step (b2) of irradiating the surface of the resin body with ultraviolet rays after the step (b1).

A method for manufacturing a light emitting device according to another embodiment of the present disclosure includes a step (a) of preparing a light emitting element having an upper surface and a positive electrode and a negative electrode provided on the side opposite to the upper surface, and the surface having unevenness. And a step (b) of forming a translucent member having at least the pattern and covering at least the upper surface of the light emitting element, the step (b) being formed by curing an uncured silicone resin raw material. The main surface of the translucent sheet, the plurality of convex portions of the mold having a plurality of convex portions are opposed to each other, and the main surface is pressed by pressing the die against the main surface of the translucent sheet in a heated state. A step (b1) of forming a plurality of concave portions on the substrate, a step (b2) of irradiating the main surface of the transparent sheet with ultraviolet rays after the step (b1), and a step of exposing the transparent sheet irradiated with ultraviolet rays. Arranging on the upper surface side of the light emitting element (b3).

A light emitting device according to another embodiment of the present disclosure is a translucent member including a light emitting element having an upper surface and a main surface that covers at least the upper surface of the light emitting element and is located above the upper surface of the light emitting element. with the door, the main surface of the light transmissive member has a plurality of recesses obtained by infrared spectroscopy, the absorption spectrum for the light-transmitting member wavenumber 3700 cm ^-1 of less than super 3000 cm ^-1 absorption of Si-OH caused appearing in range is greater than the absorption in the range of the absorption spectrum for silicone resin, Si-CH ₃ appearing in the vicinity of wave number 2960 cm ^-1 and around 800 cm ^-1 of the absorption spectrum for the light transmissive member absorption peak attributed, respectively, smaller than the absorption peak in the vicinity of wave number 2960 cm ^-1 and around 800 cm ^-1 of the absorption spectra for silicone resins.

A light emitting device according to another embodiment of the present disclosure is a translucent member including a light emitting element having an upper surface and a main surface that covers at least the upper surface of the light emitting element and is located above the upper surface of the light emitting element. The main surface of the translucent member has a plurality of recesses, and the instantaneous adhesive force of the main surface of the translucent member is lower than the instantaneous adhesive force of the silicone resin.

A light emitting device according to another embodiment of the present disclosure is a translucent member including a light emitting element having an upper surface and a main surface that covers at least the upper surface of the light emitting element and is located above the upper surface of the light emitting element. And the main surface of the translucent member has a plurality of recesses, and when heated at a temperature of 300° C. for 40 minutes, a change in depth of the plurality of recesses before and after heating is: It is within the range of 25% or less.

According to an embodiment of the present disclosure, a novel method for imparting a fine uneven shape is provided.

3 is a flowchart showing an outline of a method of manufacturing a translucent member according to the first embodiment of the present disclosure. FIG. 4 is a schematic cross-sectional view for explaining an exemplary manufacturing method of the translucent member according to the first embodiment of the present disclosure. It is a schematic plan view showing an example of the arrangement of convex portions 210. FIG. 4 is a schematic cross-sectional view for explaining an exemplary manufacturing method of the translucent member according to the first embodiment of the present disclosure. FIG. 4 is a schematic cross-sectional view for explaining an exemplary manufacturing method of the translucent member according to the first embodiment of the present disclosure. FIG. 6 is a perspective view showing an example of a translucent member 140. FIG. 8 is a cross-sectional view schematically showing the structure of an exemplary light emitting device obtained by the method for manufacturing a light emitting device according to the second embodiment of the present disclosure. 9 is a flowchart showing an example of a method for manufacturing the light emitting device according to the second embodiment of the present disclosure. It is a figure for demonstrating the step which may be included in step S22 shown in FIG. FIG. 3 is a schematic cross-sectional view showing an exemplary configuration of a light emitting body 100U having a light emitting element 110A and a translucent resin body 140U. It is a figure for demonstrating the step which may be included in step S21 shown in FIG. FIG. 6 is a schematic cross-sectional view for explaining an exemplary method for manufacturing light emitting body 100U. FIG. 6 is a schematic cross-sectional view for explaining an exemplary method for manufacturing light emitting body 100U. FIG. 6 is a schematic cross-sectional view for explaining an exemplary method for manufacturing light emitting body 100U. FIG. 6 is a schematic cross-sectional view for explaining an exemplary method for manufacturing light emitting body 100U. FIG. 6 is a schematic cross-sectional view for explaining an exemplary method for manufacturing light emitting body 100U. FIG. 6 is a schematic cross-sectional view for explaining an exemplary method for manufacturing light emitting body 100U. FIG. 8 is a schematic cross-sectional view for explaining the method for manufacturing the light emitting device according to the second embodiment of the present disclosure. FIG. 8 is a schematic cross-sectional view for explaining the method for manufacturing the light emitting device according to the second embodiment of the present disclosure. It is a typical top view showing an example of compound board 400A which has substrate 410A and the 1st electric conduction part 411A and the 2nd electric conduction part 412A provided on substrate 410A. It is a perspective view showing an example of the appearance of light-emitting device 100B. FIG. 22 is a diagram schematically showing a cross section of the light emitting device 100B shown in FIG. 21 taken along the YZ plane in FIG. 21 at a position near the center of the light emitting device 100B. 9 is a flowchart showing another example of the method for manufacturing the light emitting device according to the second embodiment of the present disclosure. FIG. 24 is a diagram for explaining steps that may be included in step S24 shown in FIG. 23. FIG. 11 is a schematic cross-sectional view for explaining another example of the method for manufacturing the light emitting device according to the second embodiment of the present disclosure. FIG. 11 is a schematic cross-sectional view for explaining another example of the method for manufacturing the light emitting device according to the second embodiment of the present disclosure. FIG. 11 is a schematic cross-sectional view for explaining another example of the method for manufacturing the light emitting device according to the second embodiment of the present disclosure. FIG. 11 is a schematic cross-sectional view for explaining another example of the method for manufacturing the light emitting device according to the second embodiment of the present disclosure. FIG. 11 is a cross-sectional view schematically showing another example of a light emitting device obtained by the method for manufacturing a light emitting device according to the second embodiment. FIG. 24 is a diagram for explaining another example of steps that can be included in step S24 shown in FIG. 23. FIG. 14 is a schematic cross-sectional view for explaining yet another example of the method for manufacturing the light emitting device according to the second embodiment of the present disclosure. FIG. 14 is a schematic cross-sectional view for explaining yet another example of the method for manufacturing the light emitting device according to the second embodiment of the present disclosure. FIG. 14 is a schematic cross-sectional view for explaining yet another example of the method for manufacturing the light emitting device according to the second embodiment of the present disclosure. FIG. 14 is a schematic cross-sectional view for explaining yet another example of the method for manufacturing the light emitting device according to the second embodiment of the present disclosure. FIG. 11 is a top view schematically showing the outer appearance of an exemplary light emitting device obtained by the method for manufacturing a light emitting device according to the third embodiment of the present disclosure. FIG. 11 is a cross-sectional view schematically showing the structure of an exemplary light emitting device obtained by the method for manufacturing a light emitting device according to the third embodiment of the present disclosure. FIG. 9 is a diagram for explaining another example of steps that can be included in step S21 shown in FIG. 8. It is a typical top view showing an example of compound board 300F. FIG. 14 is a schematic top view for explaining the method for manufacturing the light emitting device according to the third embodiment of the present disclosure. FIG. 11 is a schematic cross-sectional view for explaining the method for manufacturing the light emitting device according to the third embodiment of the present disclosure. FIG. 11 is a schematic cross-sectional view for explaining the method for manufacturing the light emitting device according to the third embodiment of the present disclosure. FIG. 11 is a cross-sectional view schematically showing the structure of another exemplary light emitting device obtained by the method for manufacturing a light emitting device according to the third embodiment of the present disclosure. FIG. 14 is a cross-sectional view schematically showing the structure of still another exemplary light emitting device obtained by the method for manufacturing a light emitting device according to the third embodiment of the present disclosure. It is a figure which shows the surface shape of the translucent sheet obtained after mold separation. It is a figure which shows the cross-sectional profile of the translucent sheet obtained after mold separation. It is a figure which shows the surface shape of the transparent sheet after irradiation of ultraviolet rays. It is a figure which shows the cross-sectional profile of the transparent sheet after irradiation of ultraviolet rays. FIG. 7 is a diagram showing a surface shape of the sample of Example 2 after irradiation with ultraviolet rays. 5 is a diagram showing a cross-sectional profile after irradiation of ultraviolet rays regarding the sample of Example 2. FIG. It is a figure which shows the surface shape of the resin sheet after mold separation. FIG. 7 is a diagram showing a surface shape of a sample of Example 3; 7 is a diagram showing a surface shape of a sample of Comparative Example 1. FIG. 3 shows an infrared spectrum of transmitted light regarding a sample of Reference Example 1, obtained by a Fourier transform infrared spectrophotometer. It is a figure which expands and shows a part of FIG. 53, and shows the infrared spectrum of the transmitted light regarding the sample of the reference example 1. FIG. It is a figure which expands and shows a part of FIG. 53, and shows the infrared spectrum of the transmitted light regarding the sample of the reference example 1. FIG. It is a figure which shows the measurement result regarding the tackiness of the surface of each sample of the reference example 2, the reference example 3, and the comparative example 2.

Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. The following embodiments are exemplifications, and the method for forming a translucent member and the method for manufacturing a light emitting device according to the present disclosure are not limited to the following embodiments. For example, the numerical values, shapes, materials, steps, 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 the sake of easy understanding, and the dimensions, shapes, and sizes of the components in the actual translucent member, the light-emitting device, and the manufacturing device may differ from each other. It may not reflect the relationship. Further, in order to avoid making the drawings excessively complicated, some of the elements may not be shown.

In the following description, components having substantially the same function are denoted by common reference numerals, and the description may be omitted. In the following description, terms indicating a particular direction or position (for example, “upper”, “lower”, “right”, “left” and another term including those terms) may be used. However, those terms are only used for the sake of clarity in the relative orientation or position in the referenced drawings. In the drawings other than the present disclosure, the actual product, the manufacturing apparatus, etc., the same as the referenced drawings, as long as the relative directions or positions are the same in terms such as “upper” and “lower” in the referenced drawings. It does not have to be arranged. In the present disclosure, “parallel” includes a case where two straight lines, sides, surfaces, etc. are in the range of 0° to ±5° unless otherwise specified. Further, in the present disclosure, “vertical” or “orthogonal” includes a case where two straight lines, sides, surfaces, etc. are in the range of about 90° to ±5° unless otherwise specified.

(First embodiment)
FIG. 1 is a flowchart showing an outline of a method of manufacturing a translucent member according to the first embodiment of the present disclosure. The method for manufacturing the light-transmissive member illustrated in FIG. 1 is generally performed by pressing a mold having a plurality of protrusions onto the main surface of the resin body in a heated state, so that the main surface of the resin body is pressed. The method includes a step of forming a plurality of recesses (step S11) and a step of irradiating the main surface of the resin body with ultraviolet rays after forming the plurality of recesses (step S12).

As described above, in the imprint method, which is one of the methods for forming the fine uneven shape, the uncured thermoplastic resin or the ultraviolet curable resin is used as the object to be pressed against the mold. On the other hand, in the embodiment of the present disclosure, the mold is pressed against a resin body containing a silicone resin that is a thermosetting resin, particularly a resin body in a cured state. The idea of pressing the mold against the cured resin body instead of the uncured state and the point of irradiating the thermosetting resin with ultraviolet rays are new ideas. According to an embodiment of the present disclosure, a resin body including a silicone resin, which is a cured resin body, is irradiated with ultraviolet rays after forming a plurality of recesses using a mold, for example. By doing so, the shape formed by pressing the mold can be fixed. According to the embodiment of the present disclosure, for example, it becomes possible to give a fine uneven shape to the surface of the thermosetting resin after curing.

Hereinafter, an embodiment of a method for manufacturing a translucent member will be described in detail with reference to the drawings.

First, as shown in FIG. 2, a resin body 140X is prepared. In the example shown in FIG. 2, the resin body 140X has a plate shape as a whole and has a planar main surface 140a. Here, the resin body 140X is a plate-shaped member, but the shape of the resin body 140X is arbitrary. In FIG. 2, the shape of the main surface 140a, which corresponds to the upper surface of the resin body 140X, is not limited to a flat surface and may be a curved surface.

The resin body 140X has a light-transmitting property and is provided with an uneven shape, and then, for example, can be arranged on the light emitting side of a light emitting element, a light emitting device or the like as an optical member such as a protective member or a light diffusing member. In addition, the terms “translucent” and “translucent” in the present specification are construed to include showing diffusibility with respect to incident light, and are not limited to “transparent”.

The resin body 140X contains a silicone resin and is in a state after being already cured. The silicone resin in the resin body 140X contains an organic polysiloxane having at least one phenyl group in the molecule. Alternatively, the silicone resin in the resin body 140X contains an organic polysiloxane having a D unit in which two methyl groups are bonded to silicon atoms. The resin body 140X may include both of these two types of organic polysiloxane. The silicone resin in the resin body 140X may contain, for example, an organic polysiloxane having a phenyl group and having a D unit. The silicone resin composition forming the resin body 140X may include a modified silicone having a group other than the methyl group and the phenyl group introduced therein.

The resin body 140X 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 resin body 140X may be a member or the like in which a resin material containing a silicone resin is used as a base material and a light scattering filler is dispersed. As the light-reflecting filler, particles of an inorganic material or an organic material having a higher refractive index than the base material can be used. Examples of light reflective fillers include titanium dioxide, zirconium dioxide, potassium titanate, aluminum oxide, aluminum nitride, boron nitride, mullite, niobium oxide, barium sulfate, silicon oxide, various rare earth oxides (e.g., yttrium oxide, oxidized Gadolinium) and other particles. The base material forming the resin body 140X may contain a resin other than the silicone resin.

The resin body 140X may include a wavelength conversion member dispersed in the resin. Since the resin body 140X includes the wavelength conversion member, the resin body 140X can absorb at least part of the incident light and emit light having a wavelength different from the wavelength of the incident light. A typical example of the wavelength conversion member is particles such as a phosphor. A known material can be applied to the phosphor. Examples of the phosphors are YAG-based phosphors, fluoride-based phosphors such as KSF-based phosphors, nitride-based phosphors such as CASN, and β-sialon phosphors. The YAG-based phosphor is an example of a wavelength conversion material that converts blue light into yellow light, and the KSF-based phosphor and CASN are examples of a wavelength conversion material that convert blue light into red light, and a β-sialon phosphor. Is an example of a wavelength conversion material that converts blue light into green light. The phosphor may be a quantum dot phosphor.

The resin body 140X can be prepared by purchasing or manufacturing. For example, a silicone resin raw material containing a silicone resin is applied onto a support such as a substrate by a coating method such as a spray method, a casting method, a potting method or a screen printing method, and then the resin raw material on the support is cured to obtain a resin. Body 140X may be obtained. Alternatively, transfer molding, compression molding, or the like may be applied to form the resin body 140X.

Next, a mold having an uneven surface is prepared. Here, as shown in FIG. 2, a mold 200 having a plurality of convex portions 210 is used. The material of the mold 200 is not particularly limited, and for example, a general material such as hardened steel, aluminum, beryllium copper alloy, or the like can be used.

In the configuration illustrated in FIG. 2, the protrusion 210 is a triangular pyramid-shaped protrusion that protrudes from the lower surface 200b of the mold 200. FIG. 3 shows an example of the arrangement of the convex portions 210. In this example, a plurality of convex portions 210 are two-dimensionally arranged on the lower surface 200b of the mold 200 so that the tops of the protrusions are located on the lattice points of the triangular lattice. The arrangement pitch of the protrusions 210, that is, the center-to-center distance between two adjacent protrusions 210 is, for example, in the range of 0.1 μm or more and 300 μm or less, and the height of the protrusions 210, that is, from the lower surface 200b to the protrusions. The distance to the top of 210 is, for example, in the range of 0.1 μm or more and 200 μm or less. Of course, the arrangement of the convex portions 210 and the shape of each of the convex portions 210 are not limited to the examples shown in FIGS. 2 and 3, and any arrangement and shape can be adopted.

Next, as schematically shown in FIG. 2, the resin body 140X is arranged on the support body 60 having sufficient rigidity, and the mold 200 is placed with the convex 210 facing the main surface 140a of the resin body 140X. To face. Furthermore, as schematically shown by a thick arrow PS in FIG. 4, the mold 200 is pressed against the main surface 140a of the resin body 140X. At this time, the mold 200 is pressed against the resin body 140X heated to about 70° C. to 300° C. under a pressure of about 50 kPa to 50 MPa, so that the main surface 140a of the resin body 140X has a plurality of convex portions of the mold 200. A plurality of recesses 140q corresponding to 210 can be formed (step S11 in FIG. 1). The heating of the resin body 140X may be performed by raising the temperature around the resin body 140X, or may be performed by raising the temperature of the mold 200 and/or the support body 60.

Next, as schematically shown in FIG. 5, the main surface 140a of the resin body 140X is irradiated with ultraviolet rays by the ultraviolet ray irradiation device 500 (step S12 in FIG. 1). 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 whose main peak wavelength of light emission is 365 nm is used. When a mold made of a translucent material such as quartz is used as the mold 200, it is possible to irradiate ultraviolet rays through the mold 200.

Through the above steps, as shown in FIG. 6, the translucent member 140 having the plurality of recesses 140d on the main surface 140a is obtained. Note that in FIG. 6, the recess 140d is exaggeratedly drawn for convenience of description.

In this example, since the convex portions 210 of the mold 200 have an arrangement in which their centers are located on the lattice points of the triangular lattice, the concave portions 140d also have their centers located on the lattice points of the triangular lattice. Have an arrangement. The distance from the opening of the recess 140d to the bottom along the normal direction of the main surface 140a, that is, the depth of the recess 140d may be 0.9 μm or more. Note that, as will be described later with reference to examples, the shape of the recess 140q may change between the recess 140q and the recess 140d due to irradiation with ultraviolet light.

Translucency with respect to light having a light emission peak wavelength of a light emitting element such as an LED or a light emitting device that can be arranged on the main surface 140a side of the translucent member 140 or on the main surface 140b (the lower surface in this example) opposite to the main surface 140a. The transmittance of the member 140 is typically 60% or more. It is advantageous that the transmissivity of the translucent member 140 with respect to the light having the above-mentioned emission peak wavelength is 70% or more, and is more beneficial if it is 80% or more. The translucent member 140 may have a haze value of 50% or more. The haze value can be measured by a measuring method based on JIS K7136:2000.

According to the embodiment of the present disclosure, it is possible to further impart a shape to the surface of the resin body after curing. As described with reference to FIG. 4, the plurality of recesses 140q may be formed in the main surface 140a by pressing the convex portions 210 of the mold 200 against the main surface 140a of the heated resin body 140X. it can. In other words, it is possible to form the plurality of recesses 140q in the main surface 140a itself without performing the step of irradiating the ultraviolet rays. That is, at first glance, it seems that a translucent member having a plurality of concave portions on the surface can be obtained even if the step of irradiating the ultraviolet rays is omitted. However, as described later in Examples, when the step of irradiating ultraviolet rays is omitted, when the resin body 140X is placed under a high temperature environment of around 300° C. after pressing the mold 200, the shape of the recess 140q collapses, In an extreme case, the main surface 140a will return to a shape close to a flat surface. In other words, if the step of irradiation with ultraviolet rays is omitted, the desired shape may not be obtained.

On the other hand, in the embodiment of the present disclosure, since the main surface 140a is irradiated with ultraviolet rays after the shape is given to the main surface 140a, when the translucent member 140 is exposed to a high temperature environment of about 300° C. Even in this case, it is possible to maintain the shape of the recess 140d formed in the main surface 140a. Therefore, after obtaining the transparent member 140, the transparent member 140 can be put into a process involving high temperature. Further, in the embodiment of the present disclosure, unlike the general thermal imprinting method using an uncured resin material, the mold 200 is pressed against the cured resin body 140X, so that the resin body 140X is pressed. The mold 200 can be easily separated.

(Second embodiment)
FIG. 7 schematically illustrates a cross section of an exemplary light emitting device obtained by the method for manufacturing a light emitting device according to the second embodiment of the present disclosure. The light emitting device 100A shown in FIG. 7 includes a light emitting element 110A, a wavelength conversion member 120A, a light guide member 130A, a translucent member 140A, and a light reflective member 150A.

The light emitting element 110A is, for example, an LED, and in this example, the light emitting element 110A has an element body 111, and a positive electrode 112A and a negative electrode 114A located on the lower surface side of the light emitting element 110A. In the configuration illustrated in FIG. 7, the upper surface of the light emitting element 110A matches the upper surface 111a of the element body 111, and the positive electrode 112A and the negative electrode 114A are on the lower surface 111b of the element body 111 opposite to the upper surface of the light emitting element 110A. It is located in.

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 active layer and n-type semiconductor layers and p-type semiconductor layers sandwiching the active layer. The semiconductor laminated structure may include a light emitting capable nitride semiconductor of ultraviolet to visible range _{(In x Al y Ga 1-} xy N, 0 ≦ x, 0 ≦ y, x + y ≦ 1). The positive electrode 112A and the negative electrode 114A described above have a function of supplying a predetermined current to the semiconductor laminated structure. As shown in FIG. 7, the lower surface of the positive electrode 112A and the lower surface of the negative electrode 114A are exposed from the lower surface 100b of the light emitting device 100A. Therefore, it can be said that the light emitting device 100A has a configuration suitable for mounting by flip-chip connection. ..

In the configuration illustrated in FIG. 7, the light emitting device 100A includes a laminated structure of the wavelength conversion member 120A and the translucent member 140A above the upper surface 111a of the element body 111. The wavelength conversion member 120A has a side surface 120c located between the upper surface 120a and the lower surface 120b, and the translucent member 140A has a side surface 140c located between the upper surface 140a and the lower surface 140b. As illustrated, in this example, the side surface 120c of the wavelength conversion member 120A and the side surface 140c of the translucent member 140A are covered with the light reflecting member 150A. The light guide member 130A has a portion located between the lower surface 120b of the wavelength conversion member 120A and the upper surface 111a of the element body 111, and the other part of the light guide member 130A includes the upper surface 111a and the lower surface of the element body 111. At least a part of the side surface 111c of the element body 111, which is located between the element body 111 and the element 111b, is covered.

Here, the translucent member 140A has a plate-like structure similar to that of the translucent member 140 of the first embodiment, and as shown schematically in FIG. 7, for example, above the upper surface of the light emitting element 110A. The upper surface 140a located at is provided with a plurality of recesses 140d. The depth of the recess 140d is, for example, 0.9 μm or more. As will be described later, the plurality of recesses 140d can be formed in the translucent member 140A by a method substantially similar to that of the first embodiment. As will be described later in Examples, the instantaneous adhesive force of the translucent member 140, which is obtained based on the probe method described below, is, for example, the instantaneous adhesive force of the surface of the silicone resin which is not intentionally irradiated with ultraviolet rays. It is within the range of 50% or less.

The transmissivity of the light transmissive member 140A with respect to the light having the emission peak wavelength of the light emitting element 110A is typically 60% or more. From the viewpoint of effectively utilizing light, the transmissivity of the light transmissive member 140A at the emission peak wavelength of the light emitting element 110A is beneficially 70% or more, and more favorably 80% or more.

Here, the wavelength conversion member 120A has a plate-like shape like the translucent member 140A. The wavelength conversion member 120A contains, for example, a base material such as a silicone resin and a wavelength conversion member such as a phosphor, absorbs at least a part of the light from the light emitting element 110A, and is different from the wavelength of the incident light. It emits light of a wavelength.

The light reflective member 150A has a shape surrounding the wavelength conversion member 120A, the translucent member 140A, and the light guide member 130A, and covers at least the side surface 111c of the element body 111. Further, in the illustrated example, a part of the light reflecting member 150A covers a region of the lower surface 111b of the element body 111 except the positive electrode 112A and the negative electrode 114A. It should be noted that the term "cover" in the present specification is not limited to the aspect in which the member to be covered and the member to be covered are in direct contact with each other, and for example, by further interposing another member between these members, Are to be construed to include such an embodiment that includes a portion which is not in direct contact with. In the present specification, “light reflectivity” means that the reflectance at the emission peak wavelength of the light emitting element is 60% or more. It is more useful if the reflectance of the light reflecting member 150A at the emission peak wavelength of the light emitting element 110A is 70% or more, and further useful if it is 80% or more. Further, it is advantageous that the light reflecting member 150A has a white color.

FIG. 8 is a flowchart showing an example of a method for manufacturing a light emitting device according to the second embodiment of the present disclosure. The method for manufacturing the light-emitting device illustrated in FIG. 8 schematically includes a step of preparing a light-emitting body having a light-emitting element and a light-transmitting resin body (step S21), and a surface having an uneven pattern, And a step of forming a transparent member that covers at least the upper surface of the light emitting element (step S22). In the example described here, in the step of forming the translucent member, as shown in FIG. 9, a plurality of recesses are formed on the surface of the resin body by pressing a mold against the surface of the resin body in a heated state. And a step (step S222) of irradiating the surface of the resin body having a plurality of recesses with ultraviolet rays. The resin body to be pressed against the mold is, for example, a resin sheet formed by curing a silicone resin raw material. Hereinafter, details of an exemplary method for manufacturing the light emitting device 100A shown in FIG. 7 will be described with reference to the drawings.

[Procedure for preparing the luminous body]
First, a light emitting body having a light emitting element and a transparent resin body is prepared (step S21 in FIG. 8). Here, as illustrated in FIG. 10, a light emitting body 100U including a sheet-shaped resin body 140U disposed above the upper surface of the light emitting element 110A is prepared. FIG. 10 schematically shows a cross section when the light emitter 100U is cut perpendicularly to the upper surface 100Ua of the light emitter 100U.

The light emitting body 100U shown in FIG. 10 further includes a wavelength conversion member 120A, a light guide member 130A, and a light reflective member 150A in addition to the light emitting element 110A and the resin body 140U. As shown in FIG. 10, the light emitting body 100U includes a laminated structure of the wavelength conversion member 120A and the resin body 140U in a part thereof, and the light reflective member 150A includes the side surface 140c of the resin body 140U and the side surface of the wavelength conversion member 120A. It covers 120c. The light emitter 100U may be prepared by purchase or may be prepared by manufacturing. The light emitter 100U shown in FIG. 10 is obtained, for example, as follows.

FIG. 11 is a flowchart for explaining an exemplary manufacturing method of the light emitter 100U. The steps of preparing the light emitting body 100U include, for example, a step of preparing a light emitting element having an upper surface (step S211), a step of applying an uncured transparent resin material to the upper surface of the light emitting element (step S212), and a transparent step. Curing the light-sensitive resin material to dispose the resin body above the upper surface of the light emitting element (step S213).

First, the light emitting element 110A having the upper surface and the positive electrode 112A and the negative electrode 114A on the lower surface 111b side opposite to the upper surface is prepared (step S211 in FIG. 11). The light emitting element 110A may be prepared by purchase. Next, a support 50 such as a heat-resistant adhesive sheet or substrate is prepared, and the light emitting element 110A is placed on the support 50 with the positive electrode 112A and the negative electrode 114A facing the support 50. Here, as shown in FIG. 12, the plurality of light emitting elements 110A are temporarily fixed to the upper surface 50a of the support body 50. For simplification, FIG. 12 shows three light emitting elements 110A arranged along the left-right direction of the paper surface, but the light emitting elements 110A may be two-dimensionally arranged on the upper surface 50a.

Next, as shown in FIG. 13, the transparent first resin material 130r is applied to the upper surface 111a, which is the upper surface of the light emitting element 110A, by a dispenser or the like (step S212 in FIG. 11). The first resin material 130r includes a silicone resin, a silicone-modified resin, an epoxy resin, a phenol resin, a polycarbonate resin, an acrylic resin, a trimethylpentene resin, a polynorbornene resin, or a material containing two or more of these as a base material.

Next, as schematically shown in FIG. 14, the wavelength conversion member 120A and the resin body 140U are arranged on the first resin material 130r, and the first resin material 130r is cured. Here, the laminated sheet LB of the wavelength conversion member 120A and the resin body 140U is prepared, and the wavelength conversion member 120A and the resin body 140U are collectively arranged on the first resin material 130r. After arranging the laminated sheet LB, the light guide member 130A is formed by curing the first resin material 130r, and the resin body 140U may be arranged above the upper surface of the light emitting element 110A, as shown in FIG. Yes (step S213 in FIG. 11). After the first resin material 130r is cured, the side surface 120c of the wavelength conversion member 120A and the side surface 140c of the resin body 140U may be trimmed by using a dicing device or the like. As a result, a plurality of light emitting bodies each having a resin body 140U that covers at least the upper surface of the light emitting element 110A are obtained.

As the laminated sheet LB, for example, a phosphor sheet in which a resin in a resin material in which phosphor particles are dispersed is in a B-stage state and a translucent resin sheet are prepared, and these are attached by heat. It can be prepared by combining and obtaining a cut piece of a predetermined size with an ultrasonic cutter or the like. The phosphor sheet can be formed of a phosphor, a resin material such as a silicone resin, a second resin material containing filler particles and a solvent. As the fluorescent substance, known fluorescent substances such as the above-mentioned YAG type fluorescent substance, KSF type fluorescent substance, CASN and β-sialon fluorescent substance can be used. The translucent resin sheet can be obtained, for example, by curing an uncured silicone resin raw material. The silicone resin raw material contains a silicone resin as a base material and may additionally contain a light-reflecting filler or the like. The silicone resin as a base material typically contains an organic polysiloxane having at least one phenyl group in the molecule and/or an organic polysiloxane having a D unit. The laminated sheet LB can also be obtained by applying the above-mentioned second resin material onto the main surface of the translucent sheet by a coating method such as a spray method, a casting method, or a potting method, and curing the second resin material. Alternatively, the laminated sheet LB may be prepared by purchase. The phosphor sheet and/or the translucent sheet may be prepared by purchase.

Typically, after forming the light guide member 130A, a light reflecting member that covers the side surface 111c of the element body 111 corresponding to the side surface of the light emitting element 110A is formed. For example, as shown in FIG. 16, the structure on the support 50 is covered with the light reflective resin layer 150T. The light-reflecting resin layer 150T can be formed by, for example, applying a third resin material in which a light-reflecting filler is dispersed to the upper surface 50a of the support 50 and then curing the third resin material. As the third resin material, a material containing a silicone resin, a phenol resin, an epoxy resin, BT resin, polyphthalamide (PPA) or the like as a base material can be used. The light-scattering particles described above can be used as the light-reflecting filler. For example, transfer molding can be applied to the formation of the light reflective resin layer 150T. In the state shown in FIG. 16, the upper surface 140a of the resin body 140U is covered with the light reflective resin layer 150T.

Next, a part of the light reflecting resin layer 150T is removed from the upper surface side of the light reflecting resin layer 150T by applying a grinding process or the like to expose the upper surface 140a of the resin body 140U from the ground surface. Further, the structure on the support 50 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 position of two light emitting elements 110A adjacent to each other. Through the steps of grinding and cutting the light reflecting resin layer 150T, the light reflecting member 150A can be formed as shown in FIG. Then, the structure on the support body 50 is separated from the support body 50 to obtain the light emitting body 100U shown in FIG.

[Process of forming translucent member]
After the light emitting body 100U is prepared, a mold is pressed against the surface of the resin body in a heated state to form a plurality of recesses on the surface of the resin body, here, the upper surface 140a of the resin body 140U (step S221 in FIG. 9). ). The step of forming the recesses on the surface of the resin body can be performed in the same manner as the example of forming the plurality of recesses 140q on the main surface 140a of the resin body 140X described with reference to FIGS. ..

For example, as schematically shown in FIG. 18, similarly to the example shown in FIG. 2, the light emitting body 100U is arranged on the support body 60, and the convex portion 210 of the mold 200 having a plurality of convex portions 210 is formed by the resin body. The upper surface 140a of 140U (e.g., the main surface 140a of the resin body 140X) is opposed to the upper surface 140a. Further, for example, the ambient temperature is raised to about 70° C. to 300° C., and the mold 200 is pressed against the upper surface 140a of the heated resin body 140U in the same manner as the example shown in FIG. The heating of the resin body 140U can be performed by increasing the temperature around the light emitting body 100U.

By heating the resin body 140U and pressing the mold 200, a plurality of recesses (corresponding to the recesses 140q shown in FIG. 4) corresponding to the plurality of protrusions 210 of the mold 200 can be formed on the upper surface 140a of the resin body 140U. (Step S221 of FIG. 9). The pressing of the mold 200 against the resin body 140U may be collectively performed on the plurality of light emitters 100U as shown in FIG. 18, or may be individually performed on each of the plurality of light emitters 100U. Good. The recess 140q may be selectively formed on the upper surface 140a of the resin body 140U of the upper surface 100Ua of the light emitting body 100U, or may be formed on the entire upper surface 100Ua of the light emitting body 100U.

Next, the surface of the resin body having the plurality of recesses formed therein is irradiated with ultraviolet rays (step S222 in FIG. 9). This step can also be performed in the same manner as the example of irradiation of the main surface 140a of the resin body 140X with ultraviolet rays described with reference to FIG. For example, similarly to the example shown in FIG. 5, the ultraviolet irradiation device 500 irradiates the upper surface 140a of the resin body 140U having the plurality of recesses 140q with ultraviolet rays. The irradiation of ultraviolet rays may be selectively performed on the upper surface 140a of the resin body 140U among the upper surface 100Ua of the light emitting body 100U. By irradiation with ultraviolet rays, as shown in FIG. 19, a translucent member 140A having a plurality of recesses 140d and covering the upper surface of the light emitting element 110A is obtained. Through the above steps, the light emitting device 100A shown in FIG. 7 is obtained. Note that, in FIG. 19, as in FIG. 6, the recess 140d is exaggeratedly drawn for convenience of description. Also in the other drawings of the present disclosure, the recess 140d or the recess 140q may be exaggeratedly drawn for convenience of description.

According to the second embodiment of the present disclosure, it is possible to improve the light extraction efficiency by imparting a fine structure to the surface of the translucent member that covers the light emitting element. When the translucent member is arranged on the light emitting side of the light emitting element 110A as in the light emitting device 100A described above, thermosetting is used as the material of the translucent member in consideration of deterioration due to light from the light emitting element 110A. It is beneficial to use a hydrophilic resin. According to the embodiment of the present disclosure, it becomes possible to form a pattern of irregularities on the surface of the thermosetting resin after curing, which is advantageous in improving the light extraction efficiency. In Patent Document 2, there is no focus on covering the light emitting element with a resin material and further forming an uneven pattern on the surface of the cured resin.

In the above-mentioned example, after arranging the laminated sheet LB on the first resin material 130r provided on the upper surface of the light emitting element 110A, the first resin material 130r is cured and the laminated sheet LB is bonded above the light emitting element 110A. There is. At this time, the light guide member 130A can be formed from the first resin material 130r. The light guide member 130A has a function of reflecting the light emitted from the side surface 111c of the element body 111, which is the side surface of the light emitting element 110A, toward the upper side of the light emitting device 100A. Therefore, by forming the light guide member 130A, it is possible to improve the light utilization efficiency.

Further, in the above-described example, the light reflecting member 150A that surrounds the light guide member 130A and covers the region of the lower surface 111b of the element body 111 excluding the positive electrode 112A and the negative electrode 114A is provided in the light emitting device 100A. Therefore, leakage of light from the side surface or the lower surface of the light emitting device 100A can be suppressed, and the light utilization efficiency can be further improved.

It should be noted that the resin body 140U is once embedded inside the light-reflecting resin layer 150T, the upper surface 140a of the resin body 140U is exposed from the light-reflecting resin layer 150T, and an uneven pattern is formed on the upper surface 140a. It is a point. Conventionally, in a manufacturing method in which a translucent member such as the resin body 140U is embedded inside the light-reflecting resin layer 150T, a concavo-convex pattern is formed on the surface of the translucent member that appears on the ground surface. It was difficult to give. On the other hand, according to the embodiment of the present disclosure, it is possible to give a shape to the surface of the cured resin body 140U. Therefore, after obtaining a light emitting device that can be used as a product, it becomes possible to post-shape the translucent member, and the effect of improving the light extraction efficiency from the light emitting device can be expected.

As described with reference to FIG. 7, here, the positive electrode 112A and the negative electrode 114A are exposed from the lower surface 100b of the light emitting device 100A, and the light emitting device 100A can be mounted on a wiring board or the like by, for example, reflow. Also in the present embodiment, as in the first embodiment, since the main surface is irradiated with ultraviolet rays after the shape is applied to the surface of the translucent resin body, the translucent member 140A has a high temperature environment. Even when exposed to light, the shape of the recess 140d can be maintained. That is, the embodiments of the present disclosure are advantageous for application of a process involving high temperature 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 recess 140d before and after heating may be within a range of 25% or less. Here, the change in the depth of the recess 140d is defined as Dp, which is the average value of the depths of the recesses 140d at any 10 locations before the heating is performed, and the depth of the recess 140d at any 10 locations after the heating is performed. It can be defined by |Dq−Dp|/Dp, where Dq is the average value of

Instead of the above-mentioned support 50, a composite substrate 400A having a substrate 410A and a first conductive portion 411A and a second conductive portion 412A provided on the substrate 410A, as illustrated in FIG. 20, is used. Good. FIG. 20 shows an example of the external appearance of the composite substrate 400A when viewed from the upper surface 400a side. The substrate 410A has a through hole 414 as schematically shown in FIG. Although not shown in FIG. 20, 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 substrate 410A is used, instead of temporarily fixing the plurality of light emitting elements 110A to the support body 50 (see FIG. 12), the plurality of light emitting elements 110A are provided on the upper surface 400a side of the composite substrate 400A by flip chip connection, for example. Fixed. 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 by a thin broken line in FIG. 20 indicates the position where the light emitting element 110A is arranged. After forming the light guide member 130A and disposing the translucent resin body 140U, the structure on the upper surface 400a of the composite substrate 400A is covered with the light reflective resin layer 150T, similarly to the step described with reference to FIG. ..

After exposing the upper surface 140a of the resin body 140U from the light reflecting resin layer 150T by grinding or the like, a plurality of recesses 140d are formed in the upper surface 140a in the same manner as the example described with reference to FIGS. 18 and 19. After that, the light-reflecting resin layer 150T and the composite substrate 400A are collectively cut by a dicing device or the like at a position indicated by a thick broken line CT in FIG. 20 to obtain a plurality of light emitting devices 100B.

FIG. 21 shows an example of the external appearance of the light emitting device 100B. FIG. 22 schematically shows a cross section when the light emitting device 100B is cut in parallel with the YZ plane in FIG. 21 at a position near the center of the light emitting device 100B. As shown in FIGS. 21 and 22, the light emitting device 100B includes a light reflective member 150B that covers the side surface 140c of the translucent member 140A, and a composite substrate 400B. The composite substrate 400B includes a substrate 410B, a first conductive portion 411B, and a second conductive portion 412B. As illustrated in FIG. 22, the first conductive portion 411B and the second conductive portion 412B emit light by the bonding member 420. The positive electrode 112A and the negative electrode 114A of the element 110A are electrically connected to each other. In the configuration illustrated in FIG. 22, the light reflecting member 150B reaches the composite substrate 400B and also covers the joining member 420.

Here, the substrate 410B, the first conductive portion 411B, and the second conductive portion 412B are a part of the substrate 410A, the first conductive portion 411A, and the second conductive portion 412A shown in FIG. 20, respectively. In the configuration illustrated in FIGS. 21 and 22, the light emitting device 100B has a shape elongated in the Y axis direction with respect to the X axis direction in the drawing, and is used as a so-called side view type light emitting device.

The light emitting device 100A shown in FIG. 7 can also be obtained as follows. FIG. 23 is a flowchart showing another example of the method for manufacturing the light emitting device according to the second embodiment of the present disclosure. In the method for manufacturing a light emitting device illustrated in FIG. 23, roughly, a step of preparing a light emitting element (step S23) and a translucent member which has an uneven pattern on the surface and at least covers the upper surface of the light emitting element. And a step of forming (step S24). In this example, the step of forming the translucent member (step S24 in FIG. 23) is performed by pressing the mold against the surface of the translucent resin body in a heated state, as illustrated in FIG. The method includes a step of forming a plurality of recesses on the surface of the resin body (step S241) and a step of irradiating the surface of the resin body having the plurality of recesses with ultraviolet rays (step S242). The resin body to be pressed against the mold is a resin sheet including a translucent portion formed by curing a silicone resin raw material as a part thereof.

First, as shown in FIG. 25, a first resin layer 170 having a transparent portion 172 is prepared. The resin layer 170 may have two or more light transmitting portions 172. In the configuration illustrated in FIG. 25, the resin layer 170 has a light reflecting resin portion 174, and the respective light transmitting portions 172 are separated from each other by the light reflecting resin portion 174. In addition, in this example, each translucent part 172 includes a translucent layer 140L and a wavelength conversion layer 120L. The resin layer 170 can be obtained as follows, for example.

First, a light-reflecting resin sheet is prepared. As the material of the light-reflecting resin sheet, the above-mentioned third resin material can be used. For example, 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 forming 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, through holes are provided in the resin sheet by punching or the like. The shape of the through hole in a top view is, for example, a rectangular shape. After the through hole is formed, the inside of the through hole is filled with, for example, the above-described second resin material containing a silicone resin as a base material by a potting method, a printing method, a spray method, or the like. At this time, particles of the phosphor are settled in the second resin material filled in the through holes to cure the second resin material, thereby forming a light transmitting portion having a phosphor concentration difference in the thickness direction. It is possible to For example, it is possible to form a translucent part in which a large number 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 the second 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 inverted upside down after the second resin material is cured, a resin layer 170 having a light-reflecting resin portion 174 and a plurality of light transmitting portions 172 as shown in FIG. 25 is obtained. .. In the configuration illustrated in FIG. 25, the transparent layer 140L is a layer in the transparent portion 172 in which the concentration of phosphor particles is relatively low. Note that, in FIG. 25, these layers are illustrated as if there is a boundary between the wavelength conversion layer 120L and the transparent layer 140L, but the boundary between these layers cannot be clearly recognized. There is also.

Next, the transparent first resin material 130r is applied to the region of the resin layer 170 where the transparent portion 172 is arranged by a dispenser or the like. Further, the light emitting element 110A is prepared (step S23 in FIG. 23), and the positive electrode 112A and the negative electrode 114A are directed to the side opposite to the resin layer 170 as shown in FIG. 26, and the light emitting element 110A is placed on the first resin material 130r. To place. Accordingly, the first resin material 130r can be arranged on at least a part of the side surface 111c of the element body 111. By curing the first resin material 130r, the light guide member 130A can be formed from the first resin material 130r.

Next, as shown in FIG. 27, a light reflecting resin layer 150T as a second resin layer that covers the structure on the resin layer 170 is formed. As the material of the light-reflecting resin layer, the above-mentioned third resin material can be used similarly to the material of the above-mentioned light-reflecting resin sheet, that is, the material of the light-reflecting resin portion 174 of the resin layer 170. For example, transfer molding can be applied to the formation of the light reflective resin layer 150T.

Next, the positive electrode 112A and the negative electrode 114A of each light emitting element 110A are exposed from the ground surface by applying a grinding process or the like to remove a part of the light reflective resin layer 150T from the upper surface side of the light reflective resin layer 150T. .. Further, by cutting the resin layer 170 and the light-reflecting resin layer 150T at the positions of the two light emitting elements 110A adjacent to each other by using a dicing device or the like, the light-reflecting resin portion 174 and the light-reflecting resin layer 150T are light-reflected. By forming the member 150A, as shown in FIG. 28, a plurality of light emitters each having the same structure as the light emitter 100U shown in FIG. 10 are obtained. In this example, the transparent layer 140L and the wavelength conversion layer 120L of the transparent portion 172 of the resin layer 170 correspond to the transparent resin body 140U and the wavelength conversion member 120A.

Next, the translucent member 140A that covers at least the upper surface of the light emitting element 110A is formed from the resin body 140U. The process of forming the transparent member 140A can be performed in the same manner as the example described with reference to FIGS. 18 and 19.

For example, first, as shown in FIG. 18, the light emitting body 100U is arranged on the support body 60, and the convex portion 210 of the mold 200 having the plurality of convex portions 210 is made to face the upper surface 140a of the resin body 140U. Further, similarly to the example shown in FIG. 4, the mold 200 is pressed against the upper surface 140a of the heated resin body 140U. By heating the resin body 140U and pressing the mold 200, a plurality of recesses can be formed in the upper surface 140a of the resin body 140U (step S241 in FIG. 24).

Further, the surface of the resin body having the plurality of recesses is irradiated with ultraviolet rays (step S242 in FIG. 24). This step can also be performed in the same manner as the example of irradiation of the main surface 140a of the resin body 140X with ultraviolet rays described with reference to FIG. For example, similarly to the example shown in FIG. 5, the ultraviolet irradiation device 500 irradiates the upper surface 140a of the resin body 140U having the plurality of recesses 140q with ultraviolet rays. By irradiation with ultraviolet rays, a transparent member 140A having a plurality of recesses 140d and covering the upper surface of the light emitting element 110A is obtained. At the stage of the resin layer 170 having the light-transmitting portion 172, a plurality of recesses 140d may be formed on the surface of the light-transmitting portion 172 by the same method as the example with reference to FIGS.

(Modification of the second embodiment)
FIG. 29 shows another example of the light emitting device obtained by the method for manufacturing the light emitting device according to the second embodiment. The light emitting device 100C shown in FIG. 29 includes a light emitting element 110A, a wavelength conversion member 120A, a light guide member 130A, a light transmissive member 140A, and a light reflective member 150C, as in the example described with reference to FIG. The light reflecting member 150C surrounds the side surface of the light emitting element 110A and covers the area of the lower surface 111b of the element body 111 other than the area in which the positive electrode 112A and the negative electrode 114A are arranged, as shown in FIG. This is the same as the light reflecting member 150A of 100A. However, in this example, the light reflective member 150C does not cover the side surface 120c of the wavelength conversion member 120A and the side surface 140c of the translucent member 140A.

The light-emitting device 100C shown in FIG. 29 can be manufactured generally according to the same process as the flow shown in FIG. 23, similar to the example described with reference to FIGS. However, here, in the step of forming the light-transmissive member, as shown in FIG. 30, a step of forming a plurality of recesses on the main surface by pressing a mold against the main surface of the light-transmissive sheet in a heated state. (Step S243), a step of irradiating the main surface of the translucent sheet having a plurality of recesses with ultraviolet rays (step S244), and a step of disposing the translucent sheet irradiated with ultraviolet rays on the upper surface side of the light emitting element. (Step S245) is included. The translucent sheet to be pressed against the mold is a sheet formed by curing a silicone resin raw material. Hereinafter, the details of an exemplary manufacturing method of the light emitting device 100C will be described with reference to the drawings.

First, a light emitting element is prepared (step S23 in FIG. 23). Further, a translucent member that covers at least the upper surface of the light emitting element 110A is formed (step S24 in FIG. 23). Here, when forming the translucent member, first, a laminated sheet 170V having a wavelength conversion layer 120V and a translucent layer 140V as shown in FIG. 31 is prepared. In this example, the transparent layer 140V has a main surface 140Va and a main surface 140Vb, and the main surface 140Vb faces one main surface 120Va of the wavelength conversion layer 120V. As schematically shown in FIG. 31, the light transmitting layer 140V has a plurality of recesses 140d on the main surface 140Va. The laminated sheet 170V can be produced, for example, in the same manner as the laminated sheet LB described above.

First, a translucent resin sheet having a main surface (hereinafter, simply referred to as “translucent sheet” for simplicity) is prepared. The translucent sheet can be obtained, for example, by curing an uncured silicone resin raw material. After preparation of the translucent sheet, a mold is pressed against the main surface of the translucent sheet in a heated state to form a plurality of recesses on the main surface of the translucent sheet (step S243 in FIG. 30). The resin body 140X described above is an example of a translucent sheet. The step of forming the recesses on the main surface of the translucent sheet may be performed in the same manner as the example of forming the plurality of recesses 140q on the main surface 140a of the resin body 140X described with reference to FIGS. 2 to 4. You can For example, similarly to the example shown in FIG. 2, a light-transmitting sheet is arranged on the support 60, and the mold 200 is pressed against the main surface of the light-transmitting sheet in a heated state in the same manner as the example shown in FIG. ..

Next, the main surface of the translucent sheet, in which a plurality of concave portions corresponding to the plurality of convex portions 210 of the mold 200 are formed, is irradiated with ultraviolet rays (step S244 in FIG. 30). This step can also be performed in the same manner as the example of irradiation of the main surface 140a of the resin body 140X with ultraviolet rays described with reference to FIG. If necessary, the translucent sheet after irradiation with ultraviolet rays is cut into a predetermined size. Through the above steps, a light-transmitting sheet having a plurality of concave portions 140d on the main surface 140a, similar to the light-transmitting member 140 shown in FIG. 6, is obtained. Here, the translucent sheet has, for example, a rectangular outer shape in a top view. Further, the wavelength conversion layer 120V is formed on the main surface of the translucent sheet opposite to the main surface 140a. By forming the wavelength conversion layer 120V, a laminated sheet LB including the above-mentioned light-transmitting sheet as the light-transmitting layer 140V is obtained.

For the formation of the wavelength conversion layer 120V, the same method as the example of forming the laminated sheet LB described above can be applied. For example, a phosphor sheet in which a resin in a resin material in which phosphor particles are dispersed is in a B stage state is arranged on the main surface of the translucent sheet opposite to the main surface 140a, and these sheets are heated by heat. The laminated sheet 170V is obtained by laminating. Alternatively, the wavelength conversion layer 120V may be formed by applying the above-mentioned second resin material on the main surface of the translucent sheet opposite to the main surface 140a and then curing the second resin material. The laminated sheet 170V may be prepared by purchase. The formation of the plurality of recesses 140d may be performed after disposing the wavelength conversion layer 120V on one main surface of the translucent layer 140V. For example, after forming the wavelength conversion layer 120V on one main surface of the translucent layer 140V, a plurality of recesses 140d may be formed on the main surface of the translucent sheet opposite to the wavelength conversion layer 120V.

After that, the translucent sheet irradiated with ultraviolet rays is arranged on the upper surface side of the light emitting element (step S245 in FIG. 30). Here, as schematically shown in FIG. 31, the first resin material 130r is provided on the wavelength conversion layer 120V, and the light emitting element 110A is arranged on the first resin material 130r. At this time, the light emitting element 110A is arranged on the first resin material 130r with the upper surface 111a of the element body 111 facing the laminated sheet 170V. Accordingly, the first resin material 130r can be arranged on at least a part of the side surface 111c of the element body 111. By hardening the first resin material 130r, as shown in FIG. 32, the light guide member 130A is formed, and the above-mentioned light-transmitting sheet is arranged on the upper surface side of the light-emitting element 110A in the form of the light-transmitting layer 140V. You can Note that FIG. 31 illustrates one light emitting element 110A, but as in the example of disposing a plurality of light emitting elements 110A on the resin layer 170 described with reference to FIG. It goes without saying that a plurality of light emitting elements 110A may be arranged.

Next, for example, the above-described third resin material is applied to the laminated sheet 170V, the structure on the laminated sheet 170V is covered with the third resin material, and the third resin material is cured. By curing the third resin material, as shown in FIG. 33, it is possible to form the light reflective resin layer 150T that covers the light emitting element 110A and the light guide member 130A. For example, transfer molding can be applied to the formation of the light reflective resin layer 150T.

Then, the positive electrode 112A and the negative electrode 114A are exposed from the ground surface by a grinding process or the like, and the laminated sheet 170V and the light reflective resin layer 150T are cut into a desired shape by using a dicing device or the like, as shown in FIG. Through the above steps, the light-transmissive member 140A and the wavelength conversion member 120A are formed from the laminated sheet 170V, and the light-reflective member 150C is formed from the light-reflective resin layer 150T, whereby the light-emitting device 100C shown in FIG. 29 is obtained. .. Here, a light-transmitting sheet in which a plurality of recesses 140d are formed in the light-transmitting layer 140V of the wavelength conversion layer 120V and the light-transmitting layer 140V of the laminated sheet 170V is used. However, the present invention is not limited to this example, and a phosphor sheet having a plurality of recesses formed by applying a method similar to the method described with reference to FIGS. 2 to 5 may be used as the wavelength conversion layer 120V. .. At this time, the transparent layer 140V may be omitted and the transparent member located above the upper surface of the light emitting element 110A may be formed from the wavelength conversion layer 120V.

In the present embodiment, it is not essential that the main surface 140a having the recess 140d constitutes the upper surface of the light emitting device. The main surface 140a in which the recess 140d is formed may be opposed to the upper surface of the light emitting element or the light emitting body. Alternatively, an uneven pattern may be formed on both the main surface 140a and the main surface 140b. The inside of the recess 140d may be filled with air or may be filled with a material having a refractive index different from that of the material forming the translucent member 140A. In any case, the point that an uneven pattern is formed on the surface of the translucent member 140A is common to the above-described examples.

(Third Embodiment)
In the examples so far, the recess 140d is formed by pressing the mold 200 against the translucent plate-shaped or sheet-shaped structure and further irradiating it with ultraviolet rays. However, as described below, it is not essential in the embodiments of the present disclosure that the object to which the concavo-convex pattern is applied has a plate-like or sheet-like structure.

35 and 36 show an example of a light emitting device obtained by the method for manufacturing a light emitting device according to the third embodiment. 35 shows an exemplary external appearance of the light emitting device as seen from the upper surface side, and FIG. 36 shows a cross section taken along the line XXXVI-XXXVI of FIG.

The light emitting device 100E shown in FIGS. 35 and 36 schematically includes a light emitting element 110B, a resin portion 350 surrounding the light emitting element 110B, and a resin package 300 having a pair of conductive leads 361 and 362. A recess 350e is provided in the center of the resin portion 350 of the resin package 300, and the light emitting element 110B is arranged inside the recess 350e. The resin part 350 is formed of, for example, a third resin material in which a light-reflecting filler is dispersed, as in the above-described light-reflecting members 150A to 150C, and reflects the light beam emitted from the light emitting element 110B to emit light. It has a function of emitting light from the upper surface 100a side of the device 100E.

As shown in FIG. 36, part of the upper surface 361a of the conductive lead 361 and part of the upper surface 362a of the conductive lead 362 form part of the bottom surface 350f of the recess 350e, and the lower surface 361b of the conductive lead 361 and The lower surface 362b of the conductive lead 362 is exposed from the lower surface 100b of the light emitting device 100E. Here, the light emitting element 110B is fixed on the conductive lead 361 by the joining member 360. The material forming the joining member 360 is 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.

35 and 36, the light emitting element 110B has a positive electrode 112B and a negative electrode 114B on the upper surface 110a opposite to the lower surface 110b. Conductive wires 372 and 371 made of Au, Al, Cu or the like are connected to the positive electrode 112B and the negative electrode 114B, respectively. In this example, the conductive wire 372 electrically connects the positive electrode 112B to the conductive lead 362, and the conductive wire 371 electrically connects the negative electrode 114B to the conductive lead 361.

The light emitting device 100E further includes a translucent member 340 located inside the recess 350e. As schematically shown in FIG. 36, the translucent member 340 covers the light emitting element 110B and the conductive wires 371 and 372. Further, as schematically shown in FIG. 36, the translucent member 340 has a plurality of recesses 340d arranged two-dimensionally on the upper surface 340a located above the upper surface 110a of the light emitting element 110B. In this example, the upper surface 340a of the translucent member 340 is aligned with the upper surface 350a of the resin portion 350, and the upper surface 340a constitutes the upper surface 100a of the light emitting device 100E together with the upper surface 350a.

Hereinafter, an exemplary method for manufacturing the light emitting device 100E will be described. The light emitting device 100E shown in FIGS. 35 and 36 can be schematically manufactured according to the same steps as the flow shown in FIG. However, here, in the step of preparing the light emitting body, as shown in FIG. 37, a step of preparing a light emitting element having an upper surface (step S214), and covering the light emitting element with a silicone resin raw material and curing the silicone resin raw material. And a step of forming a resin body (step S215). The process of forming the translucent member may be similar to the example described with reference to FIG. 9.

In preparing the light emitting body (step S21 in FIG. 8), first, the light emitting element 110B and the resin package 300 are prepared (step S214 in FIG. 37). Here, the resin package 300 can be prepared in the form of a composite substrate that includes a plurality of units that form the resin package 300. FIG. 38 shows an example of a composite substrate. The composite substrate 300F illustrated in FIG. 38 includes a conductive lead frame 360F and a resin portion 350F provided with a plurality of recesses 350e. In FIG. 38, four of the plurality of units each including the recess 350e are taken out and shown.

As schematically shown in FIG. 38, the lead frame 360F is arranged between a plurality of sets of the conductive lead 361 which is the first conductive member and the conductive lead 362 which is the second conductive member, and a set adjacent to each other. And a plurality of connecting portions 363 that connect these sets to each other. The conductive leads 361 and 362 may have, for example, a base material formed of Cu and a metal layer that covers the base material. The metal layer that coats the base material is, for example, a plating layer containing Ag, Al, Ni, Pd, Rh, Au, Cu, or an alloy thereof.

Part of the conductive lead 361 and part of the conductive lead 362 are exposed at the bottom of each recess 350e of the resin portion 350F. Each of the set 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 forming 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 disposing the lead frame 360F in the cavity of the mold, filling the inside of the cavity with the third resin material, and curing the third resin material.

Next, as shown in FIG. 39, the light emitting element 110B is arranged in each recess 350e, and the positive electrodes 112B and the negative electrodes 114B are electrically connected to the conductive leads 361 and 362 by the conductive wires 371 and 372. In this example, the positive electrode 112B and the negative electrode 114B are connected to the conductive leads 362 and 361 respectively, but the positive electrode 112B may be connected to the conductive lead 361 and the negative electrode 114B may be connected to the conductive lead 362. ..

Further, each recess 350e is filled with a silicone resin raw material containing an uncured silicone resin, and the silicone resin raw material is cured to form a translucent resin body 340Z that covers the light emitting element 110B (step S215 in FIG. 37). ). The silicone resin raw material for forming the resin body 340Z may be the same material as the material of the resin body 140X described above. That is, the silicone resin in the resin body 340Z is typically an organic polysiloxane having at least one phenyl group in the molecule and/or an organic polysiloxane having a D unit in which two methyl groups are bonded to a silicon atom. Contains siloxane. The silicone resin raw material may be a raw material in which a light-reflecting filler or the like is further dispersed.

Through the above steps, as shown in FIG. 39, a repeating structure in which a plurality of light emitting elements 100Y each having a light emitting element 110B and a transparent resin body 340Z are used as a unit is obtained. Here, similarly to the example described with reference to FIGS. 18 and 19, a concavo-convex pattern is formed on the upper surface of the resin body 340Z.

For example, as schematically shown in FIG. 40, the light emitting body 100Y is arranged on the support body 60, and the convex portion 210 of the mold 200 is opposed to the upper surface 340a of the resin body 340Z. Further, for example, the ambient temperature is raised, and the mold 200 is pressed against the upper surface 340a while the resin body 340Z is heated. By pressing the mold 200, a plurality of recesses 340q are formed on the upper surface 340a of the resin body 340Z (step S221 in FIG. 9). In this example, the recess 340q is selectively formed on the upper surface 340a of the resin body 340Z, but the recess 340q may be formed on the upper surface 350a of the resin portion 350F.

Next, for example, the ultraviolet irradiation device 500 irradiates the upper surface 340a of the resin body 340Z having the plurality of recesses 340q with ultraviolet rays (step S222 in FIG. 9). By irradiating with ultraviolet rays, as shown schematically in FIG. 41, it is possible to form the translucent member 340 covering the upper surface 110a of the light emitting element 110B from the resin body 340Z and having the plurality of recesses 340d in the upper surface 340a. After that, a plurality of light emitting devices 100E can be obtained by cutting the resin portion 350F and the connecting portion 363 of the lead frame 360F at a position between two adjacent light emitting bodies 100Y with a dicing device or the like.

A wavelength conversion member that covers the light emitting element 110B may be formed prior to the formation of the resin body 340Z. For example, the wavelength conversion member is formed by applying the second resin material to the inside of each recess 350e so as to cover the light emitting element 110B and curing the second resin material. Further, the resin body 340Z is formed on the wavelength conversion member. Then, by performing the steps described with reference to FIGS. 40 and 41, the light emitting device 100F illustrated in FIG. 42 is obtained. The light emitting device 100F has a wavelength conversion member 320A that covers the light emitting element 110B and a translucent member 340 that covers the wavelength conversion member 320A inside the recess 350e. A plurality of recesses 340d are provided on the upper surface 340a of the translucent member 340.

Alternatively, a second resin material containing a silicone resin may be used as a silicone resin raw material to fill each recess 350e with the second resin material. After the second resin material in the recess 350e is cured to obtain the light emitting body, the same steps as the steps described with reference to FIGS. 40 and 41 are performed to obtain the light emitting device 100G illustrated in FIG. To be The light emitting device 100G has a wavelength conversion member 320B that covers the light emitting element 110B in the recess 350e. As schematically shown in FIG. 43, the wavelength conversion member 320B has a plurality of recesses 340d on its upper surface 320a. As described above, the plurality of recesses 320d may be formed in the wavelength conversion member 320B as the translucent member by pressing the mold and irradiating the ultraviolet rays.

Similar to the second embodiment described above, according to the third embodiment of the present disclosure, it is possible to impart a fine structure to the surface of the translucent resin body that covers the light emitting element, and The effect of improving the extraction efficiency can be expected. According to the third embodiment, it is possible to form the uneven pattern on the surface of the translucent member that covers the light emitting element after sealing the light emitting element with the resin. Also in this embodiment, since the surface of the resin body is irradiated with ultraviolet rays after the shape is applied to the surface of the transparent resin body, even if a process involving high temperature such as reflow is performed, It is possible to maintain the uneven shape of the surface of the optical member.

(Example 1)
The sample of Example 1 was prepared according to the following procedure, and the surface shapes of the sample of Example 1 were compared before and after irradiation with ultraviolet rays.

First, a translucent sheet formed by curing a silicone resin containing an organic polysiloxane having a phenyl group in its molecule was prepared. Here, as the translucent sheet, a silicone resin (model number: KE-1011) sold by Shin-Etsu Chemical Co., Ltd. is shaped into a sheet by a screen printing method, and then heated at a temperature of 150° C. for 4 hours. The silicone resin was cured by to obtain a resin sheet having a thickness of 100 μm.

Further, a mold having a plurality of convex portions on the surface was prepared. The shape of each of the protrusions was a regular triangular pyramid, and the height of the protrusion from the surface of the mold was 1.3 μm. Further, these protrusions are two-dimensionally arranged on the surface of the mold so that the respective tops are located on the lattice points of the triangular lattice, and the spacing between the tops between two adjacent protrusions is It was 3.5 μm.

Next, one main surface of the translucent sheet and the surface of the mold provided with the plurality of protrusions are opposed to each other, and the ambient temperature is raised to 150° C. The mold was pressed against the main surface of the translucent sheet with pressure. Then, the mold was separated from the translucent sheet. On the main surface of the light-transmitting sheet after separation of the mold, a plurality of recesses were formed at positions corresponding to the protrusions of the mold. 44 and 45 are images obtained by a laser microscope showing the surface shape of the light-transmitting sheet obtained after the mold separation. FIG. 45 shows a cross-sectional profile of the translucent sheet. The depth of the recess formed on the surface of the translucent sheet was in the range of about 1.1 to 1.5 μm.

Next, the main surface of the translucent sheet in which a plurality of recesses were formed was irradiated with ultraviolet rays using an ultraviolet ray irradiation device having an ultraviolet light source with the wavelength of the strongest peak at 365 nm. The irradiated ultraviolet rays had a spectrum covering the wavelength range of UVA to UVC. The irradiation amount of ultraviolet rays at this time was 23 J/cm ² , and the irradiation time was about 50 seconds.

46 and 47 show the surface shape of the translucent sheet after irradiation with ultraviolet rays. Similar to FIG. 45, FIG. 47 shows a cross-sectional profile of the light-transmitting sheet. The depth of the recesses on the surface of the translucent sheet after irradiation with ultraviolet rays was in the range of about 1.0 to 1.4 μm, and no significant change was observed in the depth of the recesses before and after irradiation with ultraviolet rays. However, it was found from the comparison between FIGS. 45 and 47 that the region located between the recesses was slightly sharpened by the irradiation of ultraviolet rays.

(Example 2)
A sample of Example 2 was prepared in the same manner as the sample of Example 1 except that molds having different shapes and arrangements of the plurality of convex portions were used. The shape of each of the convex portions of the mold used in the preparation of the sample of Example 2 was conical, and the height of the convex portions was 1.5 μm. Further, these protrusions are two-dimensionally arranged on the surface of the mold so that the respective tops are located on the lattice points of the triangular lattice, and the spacing between the tops between two adjacent protrusions is It was 3 μm.

48 and 49 show the surface shape of the translucent sheet after irradiation with ultraviolet rays. Similar to FIGS. 45 and 47, FIG. 49 shows a cross-sectional profile of the light-transmitting sheet. In the range shown in FIG. 49, the maximum value of the depth of the recesses on the surface of the translucent sheet after irradiation with ultraviolet rays was about 2.8 μm. As can be seen from FIG. 49, the concave portion and the region between the concave portions have a rough surface including fine convex portions of about 0.5 μm. It is speculated that this is because the mold is pressed against the surface of the translucent sheet of the cured silicone resin and the convex portion of the mold is pulled out from the surface of the translucent sheet.

(Example 3, Comparative Example 1)
Next, in order to verify the influence of heat on the shape given to the sample, the sample of Example 3 and the sample of Comparative Example 1 were manufactured by the following procedure.

First, a silicone resin (model number: LPS-3541) sold by Shin-Etsu Chemical Co., Ltd. is shaped into a sheet by a screen printing method, and then heated at a temperature of 150° C. for 4 hours to obtain a thickness of 150 μm. A resin sheet was produced. Here, LPS-3541 contains the organic polysiloxane which has a phenyl group in a molecule like KE-1011 mentioned above.

Next, a mold having a plurality of convex portions on the surface is prepared, one main surface of the resin sheet and the convex portion of the mold are opposed to each other, and the ambient temperature is raised to 300° C., and the heat press device is used. The mold was pressed against the main surface of the resin sheet with a pressure of 5 MPa. Then, the mold was separated from the resin sheet. In addition, here, a mold having a surface in which conical convex portions are two-dimensionally arranged was used, which is similar to the case of manufacturing the sample of Example 2. FIG. 50 shows the surface shape of the resin sheet after the mold is separated. The depth of the recess formed on the surface of the resin sheet was in the range of about 0.9 to 1.1 μm.

Next, the resin sheet was cut to obtain two sheets. For one of the two sheets, the ultraviolet irradiation device used in the preparation of the sample of Example 1 was used, and the surface on which the recess was formed was irradiated with an irradiation amount of 22.4 J/cm ² and an irradiation time of about 30 seconds. It was irradiated with ultraviolet rays. The other sheet was not irradiated with ultraviolet light by the ultraviolet irradiation device after the depression was formed by pressing the mold.

The two sheets were placed in an electric furnace, left at a temperature of 300° C. for 40 minutes, then taken out of the electric furnace and naturally cooled to room temperature. Of these sheets, the sheet irradiated with ultraviolet rays by the ultraviolet irradiation device was used as the sample of Example 3, and the other sheet which was not irradiated with ultraviolet rays by the ultraviolet irradiation device was used as the sample of Comparative Example 1.

FIG. 51 shows the surface shape of the sample of Example 3. From the comparison between FIG. 50 and FIG. 51, it was found that by irradiating ultraviolet rays after forming the concave portion by pressing the mold, the shape of the concave portion can be maintained even by heating at about 300° C. The depth of the recess formed on the surface of the sample of Example 3 was in the range of about 0.9 to 1.1 μm. In other words, the change in the depth of the recess before and after the heating was within the range of approximately 25% or less.

FIG. 52 shows the surface shape of the sample of Comparative Example 1. From FIG. 52, it was found that when the irradiation of ultraviolet rays was not performed, the concave shape formed on the surface by pressing the mold was almost lost by heating. The depth of the recesses remaining on the surface of the sample of Comparative Example 1 was only about 0.03 μm.

(Reference example 1)
As is clear from the comparison between FIG. 51 and FIG. 52, by irradiating the surface of the resin sheet in which the concave portions are formed by pressing the mold with ultraviolet rays at an irradiation dose of about 20 J/cm ² or more, high temperature (for example, glass transition) It was found that it is possible to maintain the shape of the recess even when exposed to a temperature above the point). It is presumed that this is because some change occurred on the surface irradiated with ultraviolet rays and its vicinity. Here, a sample of Reference Example 1 in which a resin sheet was partially irradiated with ultraviolet rays was prepared, and by infrared spectroscopic analysis, a spectrum was obtained between a portion irradiated with ultraviolet rays and a portion not irradiated with ultraviolet rays. Were compared. The sample of Reference Example 1 was produced by irradiating a part of the surface of a 150 μm-thick light-transmitting sheet formed by pre-curing the above-mentioned silicone resin LPS-3541 with ultraviolet rays. Then, the silicone resin in the translucent sheet was fully cured.

53 to 55 show infrared spectra of transmitted light regarding the sample of Reference Example 1 obtained by a Fourier transform infrared spectrophotometer. In FIGS. 53 to 55, a curve K1 shows a spectrum relating to a portion not intentionally irradiated with ultraviolet rays, and a curve K2 shows a spectrum relating to a portion intentionally irradiated with ultraviolet rays. Here, for the acquisition of infrared spectrum, Nicolet sold by Thermo Fisher Scientific Co., Ltd.
The iS50 module was used.

Refer to FIG. FIG. 54 shows an enlarged view of the range of wave numbers of 4000 to 1300 cm ^{−1 in} the spectrum of FIG. FIG. 54 also shows a further enlarged view of the range of wave numbers of 2000 to 1400 cm ⁻¹ . In the spectrum shown in FIG. 54, focusing on the range of the wave number of 3700 to 3000 cm ⁻¹ related to the absorption derived from Si—OH, the absorption peak appears near the wave number of 3400 cm ⁻¹ by the irradiation of ultraviolet rays, It was found that the absorption in the range of 3700 to 3000 cm ⁻¹ was increased.

Refer also to FIG. FIG. 55 shows an enlarged range of wave numbers of 1400 to 400 cm ^{−1 in} the spectrum of FIG. Figures 54 and 55, relating to the absorption derived from Si-CH _3, the wave number is focused on the absorption peak around 2960 cm ^-1 and 800 cm ^-1, by irradiation with ultraviolet rays, the height of each peak is lower I understood it. That is, the infrared absorption of the translucent member of the light emitting device according to the embodiment of the present disclosure is basically the same as that of a silicone resin that is not intentionally irradiated with ultraviolet rays at an irradiation amount of 20 J/cm ² or more. 3700 cm ^-1 increased in a range of less than super 3000 cm ^-1, smaller in the vicinity of wave number 2960 cm ^-1 and 800 cm ^-1. From this, the irradiation of ultraviolet rays causes a change in a very shallow region of the surface of the translucent sheet irradiated with ultraviolet rays, which partially improves the hardness of the translucent sheet. The change in shape may have been suppressed.

Next, a plurality of samples having different UV irradiation doses were prepared, and the effect of UV irradiation on the instantaneous adhesive force on the surface of the sample was verified. In the present specification, the term “tackiness” is used without distinguishing it from the term “instantaneous adhesive force”, and these terms have the same meaning. The "instantaneous adhesive force" or "tackiness" in the present specification means a value obtained by measurement by the probe method described below.

First, a resin block having a thickness of 3 mm is produced, and a plurality of test pieces having a diameter of 16 mm are prepared by cutting from the same resin block. For these test pieces, a probe was brought into contact with the surface of the resin block using a dual column tabletop tester 5966 sold by Instron Japan Company Limited, and then the probe was moved at a constant speed to move the resin block. Measure the force required to detach the probe from the surface of the. In the measurement, a stainless steel probe having a flat tip shape and a tip surface area of 1800 mm ² is used. The contact time of the probe with respect to the surface of the resin sheet and the pulling speed of the probe are 1 second and 9 mm/min, respectively. The average of the measured values of the three test pieces obtained by cutting from the same sheet is used as the measured value of tackiness.

(Reference example 2)
The samples of Reference Examples 2 and 3 and the sample of Comparative Example 2 were prepared by the following procedure. Similar to the sample of Example 3 described above, a silicone resin LPS-3541 manufactured by Shin-Etsu Chemical Co., Ltd. was shaped into a sheet by a screen printing method, and heated at a temperature of 150° C. for 4 hours to obtain a thickness. A 150 μm resin sheet was prepared. However, here, a plurality of resin sheet pieces were obtained by cutting the resin sheet without applying the shape by pressing the mold. Three resin sheet pieces were randomly extracted from these resin sheet pieces, and one main surface was irradiated with ultraviolet rays at an irradiation amount of 240 J/cm ² and an irradiation time of about 30 seconds in the same manner as the sample of Example 3. Illuminated. The resin sheet piece after irradiation with ultraviolet rays was placed in an electric furnace, left at a temperature of 300° C. for 40 minutes, then taken out of the electric furnace and naturally cooled to room temperature to obtain a sample of Reference Example 2.

(Reference example 3)
A sample of Reference Example 3 was prepared in the same manner as the sample of Reference Example 2 except that the irradiation amount of ultraviolet rays was changed to 22.4 J/cm ² .

(Comparative example 2)
A sample of Comparative Example 2 was prepared in the same manner as the sample of Reference Example 2 except that the irradiation of ultraviolet rays was not performed.

FIG. 56 shows the measurement results regarding the tackiness of the surface of each sample of Reference Example 2, Reference Example 3 and Comparative Example 2. In FIG. 56, the rightmost plot shows the measured values of the sample of Reference Example 2, and the center plot shows the measured values of the sample of Reference Example 3. In FIG. 56, the leftmost plot shows the measured values of the sample of Comparative Example 2.

As shown in FIG. 56, the measured surface tackiness of the sample of Comparative Example 2 was in the range of approximately 23 to 32 N·cm ⁻² . On the other hand, the sample of Reference Example 3 UV is irradiated at an irradiation amount of 22.4J / cm ² is roughly shows tackiness value in the range of 0.1~8N · ^{cm -2,} the irradiation of 240 J / cm ² The sample of Reference Example 2, which was irradiated with ultraviolet rays in an amount, showed a tackiness value in the range of 0.3 to 0.6 N·cm ⁻² . From this, it is possible that some changes occurred on the surface and/or in the vicinity of the surface of the resin sheet formed of the silicone resin due to intentional irradiation of ultraviolet rays. As a result, it is speculated that the tackiness of the resin surface was lowered by the intentional irradiation of ultraviolet rays. From the results shown in FIG. 56, for example, by intentionally irradiating the surface of the resin body containing the silicone resin with ultraviolet rays at an irradiation amount of about 20 J/cm ² or more, the instantaneous adhesive force of the surface of the resin body was intentionally changed. It has been found that the instantaneous adhesive force of the surface of the silicone resin which has not been irradiated with various ultraviolet rays can be reduced to, for example, 50% or less.

Embodiments of the present disclosure are applicable, for example, to the manufacture of optical elements that are located in front of a light source and that transmit at least a portion of incident light. The embodiments of the present disclosure are particularly useful for manufacturing a light emitting device having a light transmissive member that covers a light emitting element such as an LED.

100A-100C, 100E-100G Light-emitting device 100U, 100Y Light-emitting body 110, 110A, 110B Light-emitting element 110a Light-emitting element upper surface 110b Light-emitting element lower surface 112A, 112B Light-emitting element positive electrode 114A, 114B Light-emitting element negative electrode 120A Wavelength conversion member 120L , 120V Wavelength conversion layer 130A Light guide member 140, 140A Light transmissive member 140L, 140V Light transmissive layer 140U, 140X, 340Z Resin body 140a Upper surface 140b Lower surface 140d, 140q Recess 150A-150C Light reflective member 170 Resin layer 170V, LB Laminated sheet 172 Light transmissive part 174 Light reflective resin part 200 type 210 type convex part 300 Resin package 300F Composite substrate 320A, 320B Wavelength conversion member 340 Translucent member 340Z Resin body 320d, 340d, 340q Recessed part 350 Resin part 361, 362 conductive lead 371, 372 conductive wire 400A, 400B composite substrate 410A, 410B substrate 411A, 411B first conductive portion 412A, 412B second conductive portion 500 UV irradiation device

Claims (19)

A step (a) of preparing a light emitting body having a light emitting element having an upper surface and a translucent resin body that covers at least the upper surface of the light emitting element;
A step (b) of forming a translucent member which has an uneven pattern on the surface and covers at least the upper surface of the light emitting element,
The step (b) includes
Forming a plurality of concave portions on the surface by causing the plurality of convex portions of a mold having a plurality of convex portions to face the surface of the resin body and pressing the mold against the surface of the resin body in a heated state The step (b1) of
A step (b2) of irradiating the surface of the resin body with ultraviolet rays after the step (b1). The step (a) includes
A step (a1) of preparing the light emitting element, wherein the light emitting element has a positive electrode and a negative electrode on a side opposite to the upper surface;
A step (a2) of applying an uncured translucent resin material to the upper surface of the light emitting element;
A step (a3) of disposing the resin body above the upper surface of the light emitting element by curing the light transmissive resin material, the method for manufacturing a light emitting device according to claim 1. A step (a) of preparing a light emitting device having an upper surface and a positive electrode and a negative electrode provided on the side opposite to the upper surface;
A step (b) of forming a translucent member which has an uneven pattern on the surface and covers at least the upper surface of the light emitting element,
The step (b) includes
The surface of the translucent resin body formed by curing an uncured silicone resin raw material is made to face the plurality of convex portions of a mold having a plurality of convex portions, and the resin body in a heated state is Forming a plurality of concave portions on the surface by pressing the mold on the surface (b1),
A step (b2) of irradiating the surface of the resin body with ultraviolet rays after the step (b1). The step (a) includes
A step (a1) of preparing the light emitting device,
The method of manufacturing a light emitting device according to claim 1, further comprising a step (a2) of covering the light emitting element with an uncured silicone resin raw material and curing the silicone resin raw material to form the resin body. The method according to claim 1, further comprising a step (c) of forming a light-reflecting member that covers at least a side surface of the light emitting element, between the step (a) and the step (b). A method for manufacturing a light emitting device. The method for manufacturing a light emitting device according to claim 1, wherein the resin body contains an organic polysiloxane having at least one phenyl group in a molecule. The method for manufacturing a light emitting device according to claim 1, wherein the resin body contains an organic polysiloxane having a D unit in which two methyl groups are bonded to silicon atoms. A step (a) of preparing a light emitting device having an upper surface and a positive electrode and a negative electrode provided on the side opposite to the upper surface;
A step (b) of forming a translucent member which has an uneven pattern on the surface and covers at least the upper surface of the light emitting element,
The step (b) includes
The main surface of the translucent sheet formed by curing an uncured silicone resin raw material is made to face the plurality of convex portions of a mold having a plurality of convex portions, and the translucent sheet in the heated state is A step (b1) of forming a plurality of concave portions on the main surface by pressing the mold on the main surface;
After the step (b1), a step (b2) of irradiating the main surface of the translucent sheet with ultraviolet rays;
And (b3) disposing the translucent sheet irradiated with ultraviolet rays on the upper surface side of the light emitting element. The method for manufacturing a light emitting device according to claim 8, further comprising a step (c) of forming a light reflecting member that covers at least a side surface of the light emitting element after the step (b). The method for manufacturing a light emitting device according to claim 8, wherein the translucent member contains an organic polysiloxane having at least one phenyl group in a molecule. The method for manufacturing a light-emitting device according to claim 8, wherein the translucent member contains an organic polysiloxane having a D unit in which two methyl groups are bonded to silicon atoms. The method for manufacturing a light-emitting device according to claim 1, wherein the plurality of recesses after performing step (b) have a depth of 0.9 μm or more. The method for manufacturing a light-emitting device according to claim 1, wherein the irradiation amount of ultraviolet rays in step (b2) is 20 J/cm ² or more. A light emitting element having an upper surface,
A light transmissive member that covers at least the upper surface of the light emitting element, and includes a main surface located above the upper surface of the light emitting element;
The main surface of the translucent member has a plurality of recesses,
Obtained by infrared spectroscopy, the absorption of the Si-OH caused appearing in a range of less than the wave number 3700 cm ^-1 super 3000 cm ^-1 of the absorption spectrum for the light-transmitting member is greater than the absorption in the range of the absorption spectrum for silicone resin , the absorption peak of the Si-CH ₃ due appearing in the vicinity of wave number 2960 cm ^-1 and around 800 cm ^-1 of the absorption spectrum for the light-transmitting member, respectively, near the wave number 2960 cm ^-1 and around 800 cm ^-1 of the absorption spectrum for silicone resin A light-emitting device that is smaller than the absorption peak of. A light emitting element having an upper surface,
A light transmissive member that covers at least the upper surface of the light emitting element, and includes a main surface located above the upper surface of the light emitting element;
The main surface of the translucent member has a plurality of recesses,
The light emitting device, wherein the instantaneous adhesive force of the main surface of the translucent member is lower than the instantaneous adhesive force of silicone resin. A light emitting element having an upper surface,
A light transmissive member that covers at least the upper surface of the light emitting element, and includes a main surface located above the upper surface of the light emitting element;
The main surface of the translucent member has a plurality of recesses,
A light-emitting device in which, when heated at a temperature of 300° C. for 40 minutes, a change in depth of the plurality of recesses before and after heating is within a range of 25% or less. The light emitting device according to claim 14, wherein the plurality of recesses have a depth of 0.9 μm or more. The translucent member includes a silicone resin,
18. The light emitting device according to claim 14, wherein the silicone resin contains an organic polysiloxane having at least one phenyl group in the molecule. The translucent member includes a silicone resin,
19. The light emitting device according to claim 14, wherein the silicone resin contains an organic polysiloxane having a D unit in which two methyl groups are bonded to silicon atoms.

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