Light-emitting device

Abstract

To provide a light-emitting device with high light extraction efficiency. [Solution] The light-emitting device comprises a light-emitting element, a translucent member disposed on the light-emitting element, a translucent joining member that joins the translucent member and the light-emitting element and covers the outer circumference of the side surface and the upper surface of the translucent member, and a covering member that exposes the upper surface of the translucent member and covers the translucent member, the joining member, and the side surface of the light-emitting element together, wherein the refractive index of the joining member is lower than that of the translucent member.

Description

[Technical Field]

[0001] This disclosure relates to a light-emitting device. [Background technology]

[0002] A light-emitting device is disclosed, comprising: a semiconductor structural layer having a light-emitting layer; a translucent substrate provided on the semiconductor structural layer; a wavelength conversion layer disposed on the translucent substrate; a translucent covering member covering at least a portion of the side surface of the translucent substrate and being transmissive to light from the light-emitting layer; and a light-shielding member including the surface of the translucent covering member, formed to cover the entire surface consisting of the side surface of the semiconductor structural layer, the side surface of the translucent substrate, and the side surface of the wavelength conversion layer (see Patent Document 1). [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2019-192716 [Overview of the project] [Problems that the invention aims to solve]

[0004] This disclosure aims to provide a light-emitting device with high light extraction efficiency. [Means for solving the problem]

[0005] A light-emitting device according to one embodiment of the present disclosure includes a light-emitting element, a translucent member disposed on the light-emitting element, a translucent joining member that joins the translucent member and the light-emitting element and covers the outer periphery of the side surface and the upper surface of the translucent member, and a covering member that exposes the upper surface of the translucent member and covers the translucent member, the joining member, and the side surface of the light-emitting element together, wherein the refractive index of the joining member is lower than that of the translucent member. [Effects of the Invention]

[0006] According to one embodiment of the present disclosure, a light-emitting device with good light extraction efficiency can be provided. [Brief explanation of the drawing]

[0007] [Figure 1] This is a schematic top view showing the light-emitting device according to this embodiment. [Figure 2] This is a schematic cross-sectional view along line II-II in Figure 1. [Figure 3A] This is a schematic cross-sectional view showing an example of the manufacturing process of the light-emitting device according to this embodiment. [Figure 3B] This is a schematic cross-sectional view showing an example of the manufacturing process of the light-emitting device according to this embodiment. [Figure 3C] This is a schematic cross-sectional view showing an example of the manufacturing process of the light-emitting device according to this embodiment. [Figure 3D] This is a schematic cross-sectional view showing an example of the manufacturing process of the light-emitting device according to this embodiment. [Figure 3E] Figure 3D is a schematic diagram showing the joining member and the translucent member as viewed from the top side of the translucent member. [Figure 3F] This is a schematic cross-sectional view showing an example of the manufacturing process of the light-emitting device according to this embodiment. [Figure 3G] Figure 3F is a schematic diagram showing the joining member and the translucent member as viewed from the top side of the translucent member. [Figure 3H] This is a schematic cross-sectional view showing an example of the manufacturing process of the light-emitting device according to this embodiment. [Figure 3I] This is a schematic cross-sectional view showing an example of the manufacturing process of the light-emitting device according to this embodiment. [Modes for carrying out the invention]

[0008] Hereinafter, a light-emitting device according to an embodiment of the present invention (hereinafter sometimes referred to as "light-emitting device according to an embodiment") will be described with reference to the drawings. In the following description, terms indicating specific directions and positions (for example, "upper", "lower", and other terms including these terms) are used as necessary. However, these terms are used only to facilitate understanding of the invention with reference to the drawings, and the meaning of these terms does not limit the technical scope of the present invention. In addition, the same reference numerals appearing in multiple drawings indicate the same or equivalent parts or members.

[0009] In addition, the embodiments shown below are examples of the light-emitting device and the like for embodying the technical idea of the present invention, and the present invention is not limited to the following. Unless otherwise specified, the dimensions, materials, shapes, relative arrangements, and the like of the components described below are not intended to limit the scope of the present invention only thereto, but are intended to be illustrative. In addition, the content described in one embodiment is also applicable to other embodiments and modified examples. Furthermore, the size and positional relationship of members shown in the drawings may be exaggerated for clarity of explanation. In order to prevent the drawings from becoming excessively complicated, schematic diagrams in which some elements are omitted, or end views showing only a cut surface as a cross-sectional view may be used. In addition, even when the size or shape of some members changes due to processing or pressing, the same name may be used for description in some cases.

[0010] <Light-emitting device 1 according to the present embodiment> FIG. 1 is a top view schematically showing the light-emitting device according to the present embodiment. In FIG. 1, the bonding member 40 is shown with a dot pattern. Note that the bonding member 40 may be shown with the same dot pattern in other drawings. FIG. 2 is a cross-sectional view taken along the line II-II in FIG. 1. In FIG. 2, a cross-section of the light-emitting device 1 cut along a plane perpendicular to the upper surface 20a of the light-emitting element 20 is shown. The same applies to the subsequent cross-sectional views.

[0011] In each drawing, for reference, mutually orthogonal X-axis, Y-axis, and Z-axis are shown as necessary. A direction parallel to the X-axis is referred to as a first direction X, a direction parallel to the Y-axis as a second direction Y, and a direction parallel to the Z-axis as a third direction Z. Furthermore, in the first direction X, the direction the arrow points to is referred to as the +X direction, and the direction opposite to the +X direction is referred to as the -X direction. In the second direction Y, the direction the arrow points to is referred to as the +Y direction, and the direction opposite to the +Y direction is referred to as the -Y direction. In the third direction Z, the direction the arrow points to is referred to as the +Z direction, and the direction opposite to the +Z direction is referred to as the -Z direction. However, these do not limit the orientation of the light-emitting device when in use, and the orientation of the light-emitting device during use is arbitrary. Furthermore, viewing an object from the +Z direction toward the -Z direction is referred to as top view.

[0012] As shown in FIG. 1 and FIG. 2, the light-emitting device 1 includes a wiring substrate 10, a light-emitting element 20, a protective element 30, a bonding member 40, a light-transmissive member 50, and a covering member 60. Note that the light-emitting device 1 may have a configuration that does not include the protective element 30 and the wiring substrate 10.

[0013] In the light-emitting device 1, the light-emitting element 20 is disposed on the wiring substrate 10. Furthermore, in the light-emitting device 1, the protective element 30 may be disposed on the wiring substrate 10. The light-emitting element 20 has an upper surface 20a, a plurality of side surfaces 20c continuous with the upper surface 20a, and a lower surface 20b opposite to the upper surface 20a. The plurality of side surfaces 20c are continuous with the upper surface 20a and the lower surface 20b. In other words, each of the plurality of side surfaces 20c has an outer edge continuous with the outer edge of the upper surface 20a and the outer edge of the lower surface 20b. The light-emitting element 20 can emit light from the upper surface 20a, the lower surface 20b, and the side surfaces 20c.

[0014] The light-emitting element 20 has a roughly rectangular top surface 20a. For example, the external shape of the light-emitting element 20 is roughly a rectangular parallelepiped or a roughly cube. In this case, the top surface 20a and bottom surface 20b of the light-emitting element 20 are roughly rectangular, and the light-emitting element 20 has four roughly rectangular sides 20c. For example, two sides of the top surface 20a of the light-emitting element 20 are parallel to the first direction X, and the other two sides are parallel to the second direction Y. Also, the normal to the top surface 20a is parallel to the third direction Z. Note that the shape of the top surface 20a of the light-emitting element 20 may be a polygon such as a triangle or a hexagon. Furthermore, the external shape of the light-emitting element 20 may be a polygonal columnar body or a frustum.

[0015] The joining member 40 is translucent to light emitted from the light-emitting element 20. The refractive index of the joining member 40 is lower than that of the translucent member 50. The refractive index of the joining member 40 can be, for example, 1.4 or more and 1.8 or less. The joining member 40 is positioned between the upper surface 20a of the light-emitting element 20 and the lower surface 50b of the translucent member 50 to join the translucent member 50 and the light-emitting element 20, and also covers the side surface 50c of the translucent member 50 and the outer periphery of the upper surface 50a of the translucent member 50. Here, the outer periphery of the upper surface 50a of the translucent member 50 refers to a frame-shaped region along the outer edge of the upper surface 50a of the translucent member 50 in a plan view. The joining member 40 exposes the region enclosed by the outer periphery of the upper surface 50a of the translucent member 50 (i.e., the region including the center of the upper surface 50a) and covers the outer periphery.

[0016] The thickness T1 of the joining member 40 covering the upper surface 50a of the light-transmitting member 50 is thinner than the thickness T2 of the joining member 40 covering the side surface 50c of the light-transmitting member 50. Specifically, the maximum value of the thickness T1 of the joining member 40 covering the upper surface 50a of the light-transmitting member 50 is smaller than the maximum value of the thickness T2 of the joining member 40 covering the side surface 50c of the light-transmitting member 50. Furthermore, the thickness T1 of the joining member 40 covering the upper surface 50a of the light-transmitting member 50 is thinner than the thickness of the joining member 40 in the third direction Z, which is located between the upper surface 20a of the light-emitting element 20 and the lower surface 50b of the light-transmitting member 50. Specifically, the maximum value of the thickness T1 of the joining member 40 covering the upper surface 50a of the light-transmitting member 50 is smaller than the maximum value of the thickness of the joining member 40 in the third direction Z, which is located between the upper surface 20a of the light-emitting element 20 and the lower surface 50b of the light-transmitting member 50. Thickness T1 is the thickness of the joining member 40 in a direction perpendicular to the upper surface 50a. Thickness T2 is the thickness of the joining member 40 in a direction perpendicular to the side surface 50c.

[0017] The thickness T1 of the bonding member 40 covering the upper surface 50a of the light-transmitting member 50 may be constant or not. For example, the thickness T1 may be thicker at the outer edge of the upper surface 50a of the light-transmitting member 50 and thinner as it moves away from the outer edge of the upper surface 50a of the light-transmitting member 50. The thickness T2 may be constant or not. For example, the thickness T2 may be thickest near the center of the bonding member 40 in the third direction Z and thinner towards the upper and lower sides in the third direction Z. The thickness T1 is, for example, 0.001 μm or more and 1 μm or less. The thickness T2 is, for example, 1 μm or more and 50 μm or less. The thickness of the bonding member 40 located between the upper surface 20a of the light-emitting element 20 and the lower surface 50b of the light-transmitting member 50 is, for example, 1 μm or more and 50 μm or less.

[0018] The joining member 40 may further cover the side surfaces 20c of the light-emitting element 20. Specifically, the joining member 40 may cover at least a portion of the upper end side (i.e., the outer edge side connected to the upper surface 20a) of each side surface 20c of the light-emitting element 20. In this case, the joining member 40 has a side surface 40c connected to the side surface 50c of the light-transmitting member 50 and the side surface 20c of the light-emitting element 20. It is preferable that the joining member 40 covers a larger area of ​​each side surface 20c of the light-emitting element 20, and more preferably covers substantially all of each side surface 20c. That is, it is preferable that the side surface 40c of the joining member 40 is in contact with the side surface 20c at a position close to the lower end side (i.e., the side connected to the lower surface 20b) of each side surface 20c of the light-emitting element 20, and more preferably in contact with the lower end of each side surface 20c. Specifically, it is preferable that on each side surface 20c of the light-emitting element 20, a region of 75% to 100% in the height direction from the upper end is covered by the joining member 40, and it is more preferable that a region of 90% to 100% is covered by the joining member 40.

[0019] Light emitted from the light-emitting element 20 enters the translucent member 50 via the bonding member 40 and is emitted to the outside via the translucent member 50. The bonding member 40 may contain light-scattering particles as an additive. By having the bonding member 40 containing light-scattering particles cover a larger area of ​​the side surface 20c of the light-emitting element 20, more of the light emitted from the side surface 20c of the light-emitting element 20 can be guided to the lower surface 50b of the translucent member 50.

[0020] In a top view, the joining member 40 exposes the central region of the upper surface 50a of the translucent member 50 and covers its outer periphery. The joining member 40 may have an inner edge that is convex toward the center of the upper surface 50a of the translucent member 50 from each side of the upper surface 50a of the translucent member 50. In other words, in a top view, the distance L from each side of the translucent member 50 to the inner edge of the joining member 40 along each side may be longest near the midpoint of each side. Note that the distance L may be approximately constant along each side. Here, L is the distance in the direction perpendicular to each side of the upper surface 50a in a top view.

[0021] The light-transmitting member 50 is positioned on the upper surface 20a of the light-emitting element 20 via a bonding member 40. The light-transmitting member 50 has an upper surface 50a, a lower surface 50b opposite to the upper surface 50a, and a side surface 50c between the upper surface 50a and the lower surface 50b. The upper surface 50a of the light-transmitting member 50 constitutes a part of the upper surface of the light-emitting device 1 as the main light-emitting surface of the light-emitting device 1. The light-transmitting member 50 is positioned on the light-emitting element 20 via a bonding member 40 positioned on the upper surface 20a of the light-emitting element 20, such that the lower surface 50b of the light-transmitting member 50 faces the upper surface 20a of the light-emitting element 20. The light-transmitting member 50 is positioned such that the lower surface 50b of the light-transmitting member 50 is substantially parallel to the upper surface 20a of the light-emitting element 20. Preferably, the shape of the lower surface 50b of the light-transmitting member is similar to the shape of the upper surface 20a of the light-emitting element. For example, if the upper surface 20a of the light-emitting element is rectangular, it is preferable that the lower surface 50b of the light-transmitting member is also rectangular.

[0022] The lower surface 50b of the light-transmitting member 50 is a flat surface. The upper surface 50a of the light-transmitting member 50 may be a flat surface parallel to the lower surface 50b, or part or all of the upper surface 50a may have surfaces that are not parallel to the lower surface 50b. Preferably, the light-transmitting member 50 is arranged such that, when viewed from above, the lower surface 50b of the light-transmitting member 50 encloses the upper surface 20a of the light-emitting element 20.

[0023] The lower surface 50b of the light-transmitting member 50 may be the same size as the upper surface 20a of the light-emitting element 20, or it may be larger than the upper surface 20a of the light-emitting element 20. When the lower surface 50b of the light-transmitting member 50 and the upper surface 20a of the light-emitting element 20 are the same size, it is preferable that the lower surface 50b of the light-transmitting member 50 is positioned so as to overlap the upper surface 20a of the light-emitting element 20 when viewed from above. By having the outer edge of the lower surface 50b of the light-transmitting member 50 coincide with the outer edge of the upper surface 20a of the light-emitting element 20, or by having the lower surface 50b of the light-transmitting member 50 enclose the upper surface 20a of the light-emitting element 20, it becomes possible to efficiently direct the light emitted upward from the upper surface 20a of the light-emitting element onto the lower surface 50b of the light-transmitting member 50. This makes it possible to improve the brightness of the light-emitting device 1.

[0024] When the lower surface 50b of the light-transmitting member 50 is larger than the upper surface 20a of the light-emitting element 20, it is preferable that the bonding member 40 interposed between the lower surface 50b and the upper surface 20a covers the lower surface 50b of the light-transmitting member 50 that does not overlap with the upper surface 20a of the light-emitting element 20 when viewed from above. Furthermore, it is preferable that the bonding member 40 is positioned to reach the outer edge of the lower surface 50b of the light-transmitting member 50, and it is even more preferable that the entire lower surface 50b is covered by the bonding member 40. This allows more of the light emitted from the light-emitting element 20 to be incident on the lower surface 50b of the light-transmitting member 50 via the bonding member 40.

[0025] The light-transmitting member 50 may or may not contain a phosphor capable of wavelength conversion of at least a portion of the incident light.

[0026] The covering member 60 exposes the upper surface 50a of the light-transmitting member 50 and covers the side surface 50c of the light-transmitting member 50, the side surface 40c of the bonding member 40, and the side surface 20c of the light-emitting element 20 all at once. Here, when the covering member 60 covers the side surface 50c of the light-transmitting member 50, it includes both cases in which the covering member 60 covers the side surface 50c via the bonding member 40 and cases in which the side surface 50c is directly covered. Similarly, when the covering member 60 covers the side surface 20c of the light-emitting element 20, it includes both cases in which the covering member 60 covers the side surface 20c via the bonding member 40 and cases in which the side surface 20c is directly covered. If the light-emitting element 20 is arranged on the wiring board 10, the covering member 60 may further cover the upper surface of the wiring board 10. Furthermore, when the light-emitting device 1 has a protective element 30, it is preferable that the covering member 60 covers the upper surface and side surface of the protective element 30.

[0027] The covering member 60 preferably has light-shielding properties, and more specifically, preferably has light reflectivity and / or light absorption properties. In particular, it is preferable that it has light reflectivity in order to suitably reflect the light emitted from the light-emitting element 20.

[0028] By covering the side surface 40c of the joining member 40 with the covering member 60, light emitted from the side surface 20c of the light-emitting element 20 and transmitted through the joining member 40 is reflected by the covering member 60. Alternatively, the covering member 60 may also cover the lower surface 20b of the light-emitting element 20. In this case, light emitted from the lower surface 20b of the light-emitting element 20 and traveling downwards can be reflected by the covering member 60. These measures improve the light extraction efficiency in the light-emitting device 1.

[0029] The covering member 60 may consist of a single member or multiple members. In the example shown in Figure 2, the covering member 60 is composed of multiple parts, including a first covering member 61 and a second covering member 62.

[0030] In the covering member 60, the first covering member 61 is positioned on the wiring board 10 side. The first covering member 61 covers, for example, the upper surface of the wiring board 10. The first covering member 61 is in contact with the joining member 40. The first covering member 61 may also cover the lower surface 20b of the light-emitting element 20. Furthermore, if the light-emitting device 1 has a protective element 30, the first covering member 61 covers, for example, at least a portion of the side surface of the protective element 30. The first covering member 61 may also cover the lower surface of the protective element 30.

[0031] In the covering member 60, the second covering member 62 is, for example, positioned on the first covering member 61. The second covering member 62 exposes the upper surface 50a of the light-transmitting member 50, covers a portion of the side surface 40c of the joining member 40, and is in contact with the first covering member 61. Furthermore, if the light-emitting device 1 has a protective element 30, the second covering member 62 covers, for example, the upper surface of the protective element 30. The second covering member 62 may also cover a portion of the side surface of the protective element 30 that is exposed from the first covering member 61.

[0032] The side surface of the second covering member 62, together with the side surface of the wiring board 10, constitutes the side surface of the light-emitting device 1. The side surface of the second covering member 62 and the side surface of the wiring board 10 can, for example, be flush. The upper surface of the second covering member 62 may or may not be parallel to the upper surface 50a of the light-transmitting member 50.

[0033] In the light-emitting device 1, when current is supplied to the light-emitting element 20 from an external power source, the light-emitting element 20 emits light. Of the light emitted by the light-emitting element 20, the light that travels upward (i.e., towards the lower surface of the translucent member) is taken out of the light-emitting device 1 via the bonding member 40 and the translucent member 50. Also, of the light emitted by the light-emitting element 20, the light that travels downward is reflected by the covering member 60 and the wiring board 10 and taken out of the light-emitting device 1 via the light-emitting element 20, the bonding member 40 and the translucent member 50. Also, of the light emitted by the light-emitting element 20, the light that travels laterally is reflected by the covering member 60 and taken out of the light-emitting device 1 via the bonding member 40 and the translucent member 50.

[0034] In the light-emitting device 1, a bonding member 40 having a refractive index lower than that of the light-transmitting member 50 covers the outer circumference of the upper surface 50a of the light-transmitting member 50. As a result, the refractive index difference between the outer circumference of the upper surface 50a of the light-transmitting member 50 and the air located outside the light-transmitting member 50 is reduced compared to a case where the bonding member 40 does not cover the outer circumference of the upper surface 50a of the light-transmitting member 50. Therefore, light incident on the light-transmitting member 50 can more easily pass through the outer circumference of the upper surface 50a of the light-transmitting member 50, thereby improving the light extraction efficiency of the light-emitting device 1.

[0035] When the optical axes of the light-emitting element 20 and the light-transmitting member 50 coincide, the brightness of the light emitted from the upper surface 50a of the light-transmitting member 50 tends to be higher in the center of the upper surface 50a and lower around the periphery, similar to the directional characteristics of the light-emitting element 20. In the light-emitting device 1, the difference between the brightness at the periphery and the brightness at the center can be reduced by making it easier for light to pass through the periphery of the upper surface 50a of the light-transmitting member 50. This makes it possible to improve the uniformity of the brightness distribution on the main light-emitting surface of the light-emitting device 1.

[0036] Furthermore, the light-emitting device 1 can reduce color unevenness on the main light-emitting surface of the light-emitting device 1 by having a bonding member 40 having a refractive index lower than that of the light-transmitting member 50 cover the outer circumference of the upper surface 50a of the light-transmitting member 50. The reduction of color unevenness will be explained in detail below.

[0037] In the light-emitting device 1, the covering member 60 covers the side surface 50c of the light-transmitting member 50. Light that enters the light-emitting element 20 from the light-emitting element 20 and exits from the side surface 50c of the light-transmitting member 50 is reflected by the covering member 60 and returns to the light-transmitting member 50, and can be emitted from the upper surface 50a of the light-transmitting member 50. A portion of the light that reaches the upper surface 50a of the light-transmitting member 50 is emitted from the upper surface 50a, and another portion is reflected by the upper surface 50a, resulting in multiple reflections within the light-transmitting member 50. For example, consider the case where the light-emitting device 1 comprises a light-emitting element 20 that emits blue light and a light-transmitting member 50 containing a phosphor that is excited by the blue light and emits yellow light. The light-emitting device 1 emits white light from the main light-emitting surface as a mixture of blue light and yellow light. If the joining member 40 does not cover the outer periphery of the upper surface 50a of the light-transmitting member 50, the blue light reflected by the covering member 60 and incident on the side surface 50c of the light-transmitting member 50 undergoes multiple reflections within the light-transmitting member 50, causing the intensity of the wavelength-converted yellow light near the side surface 50c to be relatively stronger. As a result, the light emitted from the upper surface 50a of the light-transmitting member 50 has a relatively higher proportion of yellow light on the outer periphery of the upper surface 50a, making it prone to color unevenness known as a yellow ring. On the other hand, in the light-emitting device 1, the light incident on the light-transmitting member 50 easily passes through the outer periphery of the upper surface 50a of the light-transmitting member 50, thus reducing the number of multiple reflections near the side surface 50c of the light-transmitting member 50. As a result, the difference between the proportion of yellow light in the light emitted from the vicinity of the outer periphery of the upper surface 50a and the proportion of yellow light in the light emitted from other areas of the upper surface 50a becomes smaller, reducing color unevenness in the light-emitting device 1.

[0038] Furthermore, when the light-emitting element 20 emits blue light and the translucent member 50 contains a phosphor that is excited by the blue light and emits yellow light, the brightness of the yellow light tends to be higher near the midpoint of each side of the upper surface 50a of the translucent member 50. In the light-emitting device 1, the distance L in Figure 1 is widest near the midpoint of each side of the upper surface 50a of the translucent member 50, which makes it easier for blue light to pass through the midpoint of each side and reduces the number of multiple reflections of blue light. As a result, the amount of blue light converted to yellow light is reduced, so the difference between the brightness of the yellow light near the midpoint of each side of the upper surface 50a and the brightness of the yellow light in other areas of the upper surface 50a becomes smaller, and the color unevenness of the light-emitting device 1 can be reduced.

[0039] Furthermore, if the thickness T2 of the bonding member 40 is thick, the light emitted from the light-emitting element 20 will not enter the light-transmitting member 50 and will be more likely to be emitted directly to the outside of the light-emitting device 1. For example, if the light-emitting device 1 emits white light as a mixture of blue light and yellow light, the blue light emitted from the light-emitting element 20 will leak through the bonding member 40 to the top of the light-emitting device 1. In the light-emitting device 1, the thickness T2 is thin, about 1 μm to 50 μm, so the leakage of light emitted from the light-emitting element 20 can be reduced.

[0040] Furthermore, the joining member 40 only needs to cover the outer circumference of the upper surface 50a of the light-transmitting member 50, and does not need to cover the side surface 50c of the light-transmitting member 50. In this case as well, the above-mentioned effect resulting from the joining member 40 covering the outer circumference of the upper surface 50a of the light-transmitting member 50 remains unchanged.

[0041] The following describes in detail each element constituting the light-emitting device 1 according to the embodiment.

[0042] [Wiring board 10] The wiring board 10 is a component on which the light-emitting element 20 is arranged. The wiring board 10 comprises wiring for supplying power to the light-emitting element from the outside, and a base material 11 that supports the wiring. For example, the wiring board 10 has upper wiring 12 arranged on the upper surface on which the light-emitting element 20 is arranged, and lower wiring 13 arranged on the lower surface opposite to the upper surface. The outer shape of the base material 11 is, for example, a roughly rectangular parallelepiped or roughly cubic shape. It is preferable to use a material for the base material 11 that is an insulating material and does not easily transmit light emitted from the light-emitting element 20 or ambient light. Examples of materials for the base material 11 include ceramics such as aluminum oxide, aluminum nitride, silicon nitride, and mullite, resins such as epoxy resin, silicone resin, modified epoxy resin, urethane resin, phenolic resin, polyimide resin, BT resin, and polyphthalamide, semiconductors such as silicon, and single materials and composite materials thereof such as copper and aluminum. Among these, ceramics with excellent heat dissipation properties can be suitably used as the material for the base material 11.

[0043] The upper wiring 12 includes wiring electrically connected to the light-emitting element 20 and wiring electrically connected to the protective element 30. The lower wiring 13 includes an anode electrode and a cathode electrode that have areas for securing electrical connection to an external power supply (i.e., become electrodes of the light-emitting device 1). The upper wiring 12 and lower wiring 13 can be made of metals such as iron, copper, nickel, aluminum, gold, silver, platinum, titanium, tungsten, palladium, or alloys containing at least one of these. Furthermore, the wiring board 10 may have intermediate wiring inside and / or on the side of the base material 11 for connecting the upper wiring 12 and the lower wiring 13. The wiring board 10 may also have heat dissipation terminals on the lower side that are electrically independent from the upper wiring 12.

[0044] The wiring board 10 does not necessarily have bottom wiring 13. In this case, anode electrodes and cathode electrodes electrically connected to an external power supply may be arranged on the top or side surface.

[0045] The wiring board 10 may have a recess on its upper surface. In this case, the light-emitting device 1 may have a structure in which the light-emitting element 20 is placed at the bottom of the recess in the wiring board 10. Alternatively, the light-emitting device 1 may have a structure in which it does not include a wiring board 10. For example, the light-emitting device 1 may have a structure in which a conductive member such as a plating layer placed on the electrodes of the light-emitting element 20 and / or on the electrodes of the light-emitting element 20 is provided as an external connection electrode of the light-emitting device 1, from the covering member 60 that covers the lower surface 20b of the light-emitting element 20.

[0046] Furthermore, the wiring board 10 may use leads (specifically, thin metal plates) as wiring. In this case, the wiring board 10 has leads as wiring and a resin molded body that holds the leads as a base material. The leads can be made from the aforementioned metal or alloy and processed into a predetermined shape by rolling, punching, extrusion, wet etching, dry etching, or a combination thereof.

[0047] (Light-emitting element 20) The light-emitting element 20 can preferably be a semiconductor light-emitting element such as a light-emitting diode (LED) chip or a semiconductor laser (LD) chip. The shape and size of the light-emitting element 20 can be selected arbitrarily. The light-emitting element 20 has, for example, positive and negative electrodes on its lower surface 20b. The light-emitting element 20 is arranged on the wiring board 10. The light-emitting element 20 is flip-chip mounted on the wiring board 10 via a conductive bonding member 25, for example, with its lower surface 20b facing the wiring board 10. The conductive bonding member 25 can be a known material such as eutectic solder, conductive paste, or bump.

[0048] The light-emitting element 20 includes, for example, a semiconductor structure and a support substrate that supports the semiconductor structure. The semiconductor structure includes an n-side semiconductor layer, a p-side semiconductor layer, and a light-emitting layer sandwiched between the n-side semiconductor layer and the p-side semiconductor layer. The light-emitting layer may be a single quantum well (SQW) structure or a multiple quantum well (MQW) structure including multiple well layers. The semiconductor structure includes multiple semiconductor layers made of nitride semiconductors. The nitride semiconductor is In x Al y Ga 1-x-yThe semiconductor comprises all compositions in which the composition ratios x and y are varied within their respective ranges in the chemical formula N (0 ≤ x, 0 ≤ y, x + y ≤ 1). The emission peak wavelength of the light-emitting layer can be appropriately selected depending on the purpose. The light-emitting layer is configured to emit, for example, visible light or ultraviolet light.

[0049] The light-emitting element 20 may have one semiconductor structure on one support substrate, or it may have multiple semiconductor stacks on one support substrate. Furthermore, one semiconductor structure may have only one light-emitting layer, or it may have multiple light-emitting layers. The structure of the semiconductor structure having multiple light-emitting layers may include multiple light-emitting layers between one n-side semiconductor layer and one p-side semiconductor layer, or it may be a structure in which a stacked structure containing an n-side semiconductor layer, a light-emitting layer, and a p-side semiconductor layer in sequence is repeated multiple times.

[0050] The light-emitting element 20 includes an n electrode connected to the n-side semiconductor layer and a p electrode connected to the p-side semiconductor layer. The p electrode and the n electrode may be arranged on different sides of the semiconductor laminate or on the same side. Here, the electrodes, including the p electrode and the n electrode, are arranged on the same side of the semiconductor structure, with the side on which the electrodes are arranged forming the lower surface 20b of the light-emitting element 20, and the side of the support substrate opposite to the side on which the semiconductor structure is arranged forming the upper surface 20a of the light-emitting element 20. Examples of support substrates include insulating substrates such as sapphire and spinel (MgAl2O4), and nitride-based semiconductor substrates such as gallium nitride. It is preferable that the support substrate be made of a material that is transparent to light emitted from the light-emitting layer in order to extract the light emitted from the light-emitting layer through the support substrate. The light-emitting element 20 may also be configured without a support substrate. In this case, the side of the semiconductor structure opposite to the side on which the electrodes are arranged forms the upper surface 20a of the light-emitting element 20.

[0051] (Protection element 30) The light-emitting device 1 may include other electronic components besides the light-emitting element 20, such as a protective element 30. The protective element 30 is, for example, a Zener diode. However, the light-emitting device 1 may also be configured without the protective element 30.

[0052] (Jointing member 40) The joining member 40 is positioned between the light-emitting element 20 and the light-transmitting member 50, joining the light-emitting element 20 and the light-transmitting member 50. The joining member 40 also covers the outer circumference of the upper surface 50a of the light-transmitting member 50. Furthermore, the joining member 40 covers the side surface 50c of the light-transmitting member 50. As described above, the joining member 40 is light-transmitting and guides the light emitted from the light-emitting element 20 to the light-transmitting member 50.

[0053] For example, a translucent resin can be used as the bonding member 40. Examples of translucent resins include thermosetting resins such as epoxy resin, modified epoxy resin, silicone resin, and modified silicone resin. Among these, silicone resin, which has high heat resistance, is preferably used. When using silicone resin for the bonding member 40, either dimethyl silicone resin or phenylmethyl silicone resin may be used. Since phenylmethyl silicone resin has a higher refractive index than dimethyl silicone resin, it can improve the light extraction efficiency of the light-emitting device 1.

[0054] Furthermore, polysilazane may be used as the bonding member 40. Since polysilazane has superior weather resistance and heat resistance compared to the above-mentioned resin materials, it can be used to create a more reliable light-emitting device. Polysilazane is a polymer compound having repeating units represented by (-Si-N-) in its molecule, and examples include inorganic polysilazane, organic polysilazane, and modified polysilazane. Polysilazane is suitable as a material for the bonding member 40 of the light-emitting device 1 because it is easy to select a material with a lower refractive index than the light-transmitting member 50, and it spreads well to the light-transmitting member 50 when softened, making it easy to form a thin film.

[0055] Examples of light-scattering particles contained in the bonding member 40 include silicon dioxide, titanium dioxide, aluminum oxide, and barium titanate. One of these light-scattering particles can be used alone, or two or more can be used in combination. The inclusion of light-scattering particles in the bonding member 40 reduces unevenness in the light emission emitted from the light-emitting layer of the light-emitting element 20, and makes the distribution of light incident on the lower surface 50b of the light-transmitting member 50 more uniform. When using a silicone resin (refractive index of approximately 1.41 to 1.55 at 25°C) for the bonding member 40, it is preferable to use silicon dioxide, which has a refractive index close to that of the silicone resin, as the light-scattering particle. This reduces the decrease in light transmittance of the bonding member 40 due to the inclusion of light-scattering particles. The particle size of the light-scattering particles can be between 1 nm and 10 μm. In particular, it is preferable to use nanoparticles such as nanosilica as the light-scattering particles. Using nanoparticles allows for adjustment of the viscosity of the uncured bonding member 40. This makes it easy to position the uncured bonding member 40 at a desired location during the manufacturing process of the light-emitting device 1. Nanoparticles refer to particles with a particle size of 1 nm or more and 100 nm or less. In this specification, "particle size" refers to the average particle size. The average particle size can be measured by the Fisher Sub-Sieve Sizer method (hereinafter also referred to as the "FSSS method"). The FSSS method is a type of air permeation method that uses the resistance of air flow to measure the specific surface area and mainly determines the particle size of primary particles. The average particle size measured by the FSSS method is the Fisher Sub-Sieve Sizer's Number. The shape of light-scattering particles can be spherical, irregularly shaped, acicular, columnar, plate-like (including flaky), fibrous, or dendritic (the same applies to light-reflecting materials and / or phosphors described later). Light-scattering particles may also be hollow or porous.

[0056] (Translucent member 50) The light-transmitting member 50 is placed on the light-emitting element 20 and transmits light emitted from the light-emitting element 20 to the outside. The light-transmitting member 50 transmits 60% or more of the light from the light-emitting element 20 and / or the light obtained by wavelength conversion of the light from the light-emitting element 20 (for example, light in the wavelength range of 320 nm to 850 nm), and it is preferable that it transmits 70% or more of the light. The light-transmitting member 50 can be made of an inorganic material such as glass, ceramic, or sapphire, or an organic material such as a resin or hybrid resin containing one or more of the following: silicone resin, modified silicone resin, epoxy resin, modified epoxy resin, acrylic resin, phenolic resin, or fluororesin.

[0057] The light-transmitting member 50 may contain a phosphor capable of wavelength conversion of at least a portion of the incident light. Examples of light-transmitting members 50 containing a phosphor include a sintered phosphor or a material containing phosphor powder as described above. Alternatively, the light-transmitting member 50 may be a light-transmitting plate, which is a molded body of resin, glass, ceramic, etc., with a phosphor layer, such as a resin layer containing a phosphor or a glass layer containing a phosphor, arranged on its surface. Furthermore, the light-transmitting member 50 may contain a filler, such as light-scattering particles, depending on the purpose. If a filler, such as light-scattering particles, is included, the light-transmitting member 50 may be a resin, glass, ceramic, or other inorganic material with the filler incorporated. Alternatively, a light-scattering layer, such as a resin layer containing a filler, such as a glass layer containing a filler, may be arranged on the surface of a light-transmitting plate, which is a molded body of resin, glass, ceramic, etc.

[0058] Examples of phosphors include yttrium aluminum garnet phosphors (e.g., (Y,Gd)3(Al,Ga)5O 12 Ce), lutetium-aluminum-garnet phosphors (e.g., Lu3(Al,Ga)5O 12 Ce), terbium aluminum garnet phosphors (e.g., Tb3(Al,Ga)5O 12 :Ce), CCA-based phosphors (e.g., Ca 10 (PO4)6Cl2:Eu), SAE-based phosphors (e.g., Sr4Al 14 O25 :Eu), chlorosilicate-based phosphors (for example, Ca8MgSi4O 16 Cl2:Eu), silicate-based phosphors (for example, (Ba,Sr,Ca,Mg)2SiO4:Eu), β-sialon-based phosphors (for example, (Si,Al)3(O,N)4:Eu) or α-sialon-based phosphors (for example, Ca(Si,Al) 12 (O,N) 16 :Eu) and other oxynitride-based phosphors, LSN-based phosphors (for example, (La,Y)3Si6N 11 :Ce), BSESN-based phosphors (for example, (Ba,Sr)2Si5N8:Eu), SLA-based phosphors (for example, SrLiAl3N4:Eu), CASN-based phosphors (for example, CaAlSiN3:Eu) or SCASN-based phosphors (for example, (Sr,Ca)AlSiN3:Eu) and other nitride-based phosphors, KSF-based phosphors (for example, K2SiF6:Mn), KSAF-based phosphors (for example, K2(Si 1-x Al x )F 6-x :Mn, wherein x satisfies 0<x<1.) or MGF-based phosphors (for example, 3.5MgO·0.5MgF2·GeO2:Mn) and other fluoride-based phosphors, quantum dots having a perovskite structure (for example, (Cs,FA,MA)(Pb,Sn)(F,Cl,Br,I)3, wherein FA and MA represent formamidinium and methylammonium respectively), II-VI group quantum dots (for example, CdSe), III-V group quantum dots (for example, InP), or quantum dots having a chalcopyrite structure (for example, (Ag,Cu)(In,Ga)(S,Se)2) can be used.

[0059] As the light scattering particles, the same light scattering particles used in the bonding member 40 can be used.

[0060] Further, when a resin is used as a binder for the phosphor layer or the light scattering layer, examples of the resin include thermosetting resins such as epoxy resin, modified epoxy resin, silicone resin, and modified silicone resin.

[0061] Furthermore, the light-transmitting member 50 may have an optical film such as an anti-reflective film on its upper and / or lower surface to improve light extraction, and may also have an optical film such as a reflective film on its side surface. An example of an anti-reflective film is a silicon oxide film. When the upper surface 50a of the light-transmitting member 50 has an anti-reflective film, the outer periphery of the upper surface 50a of the light-transmitting member 50 is covered with a bonding member 40 having a refractive index smaller than that of the anti-reflective film, via the anti-reflective film. This makes it possible to obtain the same effect as described above when the bonding member 40 directly covers the outer periphery of the upper surface 50a of the light-transmitting member 50.

[0062] (Covering member 60) The covering member 60 exposes the upper surface 50a of the light-transmitting member 50 and covers the side surface 40c of the joining member 40. The covering member 60 preferably has a reflectance of 60% or more with respect to light emitted from the light-emitting element 20, and more preferably has a reflectance of 70% or more, 80% or more, or 90% or more.

[0063] The coating member 60 is preferably made of an insulating material. The coating member 60 is, for example, a member containing particles of a light-reflecting substance and a base material. Examples of base materials used for the coating member 60 include resins or hybrid resins containing one or more of the following: silicone resin, modified silicone resin, epoxy resin, modified epoxy resin, urea resin, acrylic resin, phenolic resin, bismaleimidotriazine resin, and polyphthalamide resin. Among these, it is particularly preferable to use a silicone resin that has excellent light resistance, heat resistance, electrical insulation properties, and flexibility. The base material may also be composed of an inorganic material such as an alkali metal silicate. Examples of light-reflecting substances include titanium oxide, silicon oxide, aluminum oxide, zirconium oxide, magnesium oxide, potassium titanate, barium titanate, zinc oxide, silicon nitride, aluminum nitride, boron nitride, calcium carbonate, calcium hydroxide, calcium silicate, and combinations thereof. Among these, it is preferable to use titanium oxide, which has a relatively high refractive index, from the viewpoint of light reflection.

[0064] As described above, the covering member 60 may consist of a first covering member 61 and a second covering member 62. In this case, each of the first covering member 61 and the second covering member 62 can be formed using a material selected from the materials exemplified above as materials for the covering member 60. For example, a material with high mechanical strength can be used for the second covering member 62 that constitutes the outer surface of the light-emitting device 1. In addition, a material with low elasticity and / or low linear expansion can be used for the first covering member 61 that covers the lower surface 20b of the light-emitting element 20 to alleviate the stress of resin expansion.

[0065] <Manufacturing method for a light-emitting device according to an embodiment> The following describes each manufacturing step of the method for manufacturing the light-emitting device according to the embodiment, with reference to the drawings.

[0066] Figures 3A to 3I are schematic diagrams illustrating the manufacturing process of the light-emitting device according to this embodiment. Specifically, Figures 3A, 3B, 3C, 3D, 3F, 3H, and 3I are schematic cross-sectional views illustrating an example of the manufacturing process of the light-emitting device according to this embodiment. Figures 3E and 3G are views of the joining member and the light-transmitting member, viewed from the top side of the light-transmitting member.

[0067] (Process for preparing the light-emitting element) First, as shown in Figure 3A, a light-emitting element 20 is prepared, which has an upper surface 20a, a lower surface 20b, and a plurality of side surfaces 20c connected to the upper surface 20a and the lower surface 20b. A protective element 30 is also prepared as needed. The light-emitting element 20 can be prepared by going through some or all of a plurality of processes, such as forming a semiconductor laminate and forming electrodes. In the description of the manufacturing method, "preparing" a component is not limited to manufacturing the component, but also includes acquiring the component by purchasing it, receiving it, etc.

[0068] (Process of preparing the wiring board, process of arranging light-emitting elements on the wiring board) Next, as shown in Figure 3B, a wiring board 10 is prepared, and the light-emitting element 20 is placed on the wiring board 10. Specifically, first, a wiring board 10 is prepared having a base material 11, upper wiring 12 provided on the upper surface of the base material 11, and lower wiring 13 provided on the lower surface of the base material 11. Then, the light-emitting element 20 is placed on the upper side of the wiring board 10. Here, a protective element 30 is placed together with the light-emitting element 20. The light-emitting element 20 and the protective element 30 are flip-chip mounted on the wiring board 10 via conductive bonding members 25 that are pre-placed on the wiring board 10. Note that in the placement process, the conductive bonding members 25 may be pre-placed on the light-emitting element 20 side. The conductive bonding members 25 placed on the light-emitting element 20 side include, for example, conductive members such as plating layers placed on the electrodes of the light-emitting element 20. Also, in the placement process, the conductive bonding members 25 may be placed on both the light-emitting element 20 side and the wiring board 10 side.

[0069] (Step of arranging the joining members) Next, as shown in Figure 3C, an uncured bonding member 401 is placed on at least a portion of the upper surface 20a of the light-emitting element 20. The uncured bonding member 401 will harden to form the bonding member 40 in the light-emitting device 1. The bonding member 401 can be made from the materials described above. When polysilazane is used as the material for the bonding member 401, it is preferable to include a solvent in the material to reduce its viscosity, considering the wettability with the light-emitting element 20 and the light-transmitting member 50. Examples of solvents include dibutyl ether, decane, and isononane.

[0070] The uncured bonding member 401 may be placed at one location on the upper surface 20a of the light-emitting element 20, or at multiple locations. For example, the uncured bonding member 401 can be placed only in the center of the upper surface 20a of the light-emitting element 20. Alternatively, if the upper surface 20a of the light-emitting element 20 is rectangular, the uncured bonding member 401 can be placed at the four corners of the upper surface 20a and in the center of the upper surface 20a, spaced apart from each other. Or, if the upper surface 20a of the light-emitting element 20 is rectangular, the bonding member 401 may be placed in a cross shape where two diagonally extending portions of the upper surface 20a intersect in the center of the upper surface 20a.

[0071] Here, as an example, we will describe the case where the upper surface 20a of the light-emitting element 20 is rectangular and an uncured bonding member 401 is placed at one location on the upper surface 20a of the light-emitting element 20. First, the nozzle is placed above the center of the upper surface 20a of the light-emitting element 20, and the uncured bonding member 401 is discharged from the nozzle. Then, after a predetermined amount of bonding member 401 has been discharged, the discharge is stopped. After that, the nozzle is moved away from the top of the light-emitting element 20.

[0072] The uncured bonding member 401, positioned on the upper surface of the light-emitting element 20, may be separated from the outer edge of the upper surface 20a, or it may be in contact with the outer edge of the upper surface 20a. On the upper surface of the light-emitting element 20, the uncured bonding member 401 will have a shape close to a hemisphere, circular in top view and semi-circular in side view, due to surface tension. Note that "uncured" refers to the state before the curing reaction proceeds, that is, the state before any operation to promote the curing reaction is performed. Operation to promote the curing reaction includes heating or light irradiation. Note that the curing reaction may proceed slightly before any operation to promote the curing reaction is performed, but the uncured state includes such a state.

[0073] (Step of arranging light-transmitting members) Next, as shown in Figure 3D, a translucent member 50 is prepared, and the translucent member 50 is placed on the upper surface 20a of the light-emitting element 20 via the uncured bonding member 401, and the bonding member 401 shown in Figure 3C is pressed with the lower surface 50b of the translucent member 50.

[0074] When the lower surface 50b of the translucent member 50 presses the joining member 401, the joining member 401 moves outward between the lower surface 50b of the translucent member 50 and the upper surface 20a of the light-emitting element 20. Due to this movement, the joining member 401 crawls up the side surface 50c of the translucent member 50 from between the lower surface 50b of the translucent member 50 and the upper surface 20a of the light-emitting element 20, and covers the side surface 50c. The joining member 401 that covers the side surface 50c of the translucent member 50 further crawls up the upper surface 50a of the translucent member 50, and covers at least a part of the upper surface 50a from the outer edge side. In addition, the joining member 401 that moves from between the lower surface 50b of the translucent member 50 and the upper surface 20a of the light-emitting element 20 may further cover a part or all of the side surface 20c of the light-emitting element 20. As shown in Figure 3E, the joining member 401 may have an outer edge located outside each side of the upper surface 50a and an inner edge located inside each side of the upper surface 50a when viewed from above. The inner edge of the joining member 40 may have a shape that is convex from each side of the upper surface 50a toward the center of the upper surface 50a.

[0075] Next, as shown in Figure 3F, the bonding member 401 is cured to form the bonding member 40. This joins the translucent member 50 and the light-emitting element 20 via the bonding member 40. Curing can be performed by known methods, such as heating in an oven. If the bonding member 401 contains a solvent, the solvent is removed by evaporation due to heating. The bonding member 401 can cover the side surface 50c and the top surface 50a of the translucent member 50 with a thin film due to the removal of the solvent and / or volume shrinkage due to curing. Specifically, the thickness of the bonding member 40 covering the top surface 50a of the translucent member 50 is 0.001 μm or more and 1 μm or less. The thickness of the bonding member 40 covering the side surface 50c of the translucent member 50 is 1 μm or more and 50 μm or less. When a material that softens upon heating, such as polysilazane, is used as the joining member 401, as shown in Figure 3G, during heating, the joining member 401 spreads wetter toward the center of the upper surface 50a of the translucent member 50 than in the state shown in Figure 3E. If heating is continued further, the joining member 401 hardens and the joining member 40 is obtained.

[0076] In the light-emitting device 1, it is preferable that the bonding member 40 is positioned at a distance from the wiring board 10. By positioning the bonding member 40 at a distance from the wiring board 10, it is possible to reduce the chance of the bonding member 40 having an irregular shape, which would cause light from the light-emitting element 20 to be reflected in an unintended direction. This improves the light extraction efficiency of the light-emitting device 1.

[0077] (Step of arranging the first covering member) Next, as shown in Figure 3H, the first covering member 61 is placed on the wiring board 10. The first covering member 61 is positioned to cover at least a portion of the bonding member 40. Specifically, first, an uncured first covering member 61 is placed on the wiring board 10. The uncured first covering member 61 can be placed on the wiring board 10 by, for example, potting, spraying, etc. The first covering member 61 covers, for example, the lower surface 20b of the light-emitting element 20, at least a portion of the side surface 40c of the bonding member 40, the lower surface of the protective element 30, and at least a portion of the side surface of the protective element 30. After that, the uncured first covering member 61 is cured by a known method such as heating.

[0078] (Step of placing the second covering member) Next, as shown in Figure 3I, a second covering member 62 is placed to expose the upper surface 50a of the light-transmitting member 50 and cover the side surface 40c of the joining member 40. Specifically, an uncured second covering member 62 is placed on the first covering member 61, exposing the upper surface 50a of the light-transmitting member 50 and covering the side surface 40c of the joining member 40. The uncured second covering member 62 can be placed on the first covering member 61 by, for example, potting, spraying, printing, compression molding, etc. The second covering member 62 may also cover the upper surface of the protective element 30 and a part of the side surface of the protective element 30. After that, the uncured second covering member 62 is cured by a known method to form a covering member 60 consisting of the cured first covering member 61 and the second covering member 62. This gives rise to the light-emitting device 1.

[0079] Before placing the light-emitting element 20 on the wiring board 10, a light-transmitting member 50 may be placed on the upper surface 20a of the light-emitting element 20 via a bonding member 401, and the bonding member 401 may be cured. Then, this structure may be placed on the wiring board 10.

[0080] Furthermore, the manufacturing method of the light-emitting device according to the embodiment allows for the simultaneous manufacture of multiple light-emitting devices 1. In this case, in the step of preparing the wiring board, a composite substrate is prepared that includes multiple regions which will become the wiring boards 10 of each individual light-emitting device 1 after individualization. Then, the light-emitting elements 20 and protective elements 30 are placed in each region of the prepared composite substrate, and after the above-described steps, an individualization step is performed to separate each region, thereby obtaining the light-emitting device 1 shown in Figure 1.

[0081] Although preferred embodiments have been described in detail above, the invention is not limited to the embodiments described above, and various modifications and substitutions can be made to the embodiments described above without departing from the scope of the claims.

[0082] In addition to the embodiments described above, the following further notes are disclosed. (Note 1) Light-emitting element and A light-transmitting member is placed on the light-emitting element, A translucent joining member is provided to join the light-transmitting member and the light-emitting element, and to cover the outer periphery of the side surface and the upper surface of the light-transmitting member, The device has a covering member that exposes the upper surface of the light-transmitting member and covers the light-transmitting member, the joining member, and the side surface of the light-emitting element together, A light-emitting device wherein the refractive index of the bonding member is lower than that of the light-transmitting member. (Note 2) The light-emitting device according to Appendix 1, wherein the thickness of the joining member covering the upper surface of the light-transmitting member is thinner than the thickness of the joining member covering the side surface of the light-transmitting member. (Note 3) The light-emitting device according to Appendix 2, wherein the thickness of the bonding member covering the upper surface of the light-transmitting member is 0.001 μm or more and 1 μm or less. (Note 4) The light-emitting device according to Appendix 2 or 3, wherein the thickness of the bonding member covering the side surface of the light-transmitting member is 1 μm or more and 50 μm or less. (Note 5) The joining member covers the side surface of the light-emitting element, as described in any one of Appendix 1 to 4. (Note 6) The light-emitting device according to any one of appendices 1 to 5, wherein the lower surface of the light-transmitting member and the upper surface of the light-emitting element are of the same size. (Note 7) The light-emitting device according to any one of appendices 1 to 6, wherein the bonding member is polysilazane. (Note 8) The light-emitting device according to any one of appendices 1 to 7, wherein, in a top view, the joining member has an inner edge that protrudes from each side of the upper surface of the translucent member toward the center of the upper surface of the translucent member. (Note 9) The light-emitting device according to any one of appendices 1 to 8, wherein the light-transmitting member contains a phosphor capable of wavelength conversion of at least a portion of the incident light. [Explanation of Symbols]

[0083] 1. Light-emitting device 10 Wiring board 11 Base material 12 Top wiring 13 Bottom wiring 20 Light-emitting elements 20a top surface 20b Bottom side 20c side 25 Conductive bonding member 30 protective elements 40 Joining members 40c side 50 Translucent material 50a top 50b Bottom side 50c side 60 Covering member 61 First covering member 62 Second covering member 401 Joining member

Claims

1. Light-emitting element and A light-transmitting member is placed on the light-emitting element, A translucent joining member is provided to join the light-transmitting member and the light-emitting element, and to cover the outer periphery of the side surface and the upper surface of the light-transmitting member, The device has a covering member that exposes the upper surface of the light-transmitting member and covers the light-transmitting member, the joining member, and the side surface of the light-emitting element together, A light-emitting device wherein the refractive index of the bonding member is lower than that of the light-transmitting member.

2. The light-emitting device according to claim 1, wherein the thickness of the joining member covering the upper surface of the light-transmitting member is thinner than the thickness of the joining member covering the side surface of the light-transmitting member.

3. The light-emitting device according to claim 2, wherein the thickness of the bonding member covering the upper surface of the light-transmitting member is 0.001 μm or more and 1 μm or less.

4. The light-emitting device according to claim 2, wherein the thickness of the bonding member covering the side surface of the light-transmitting member is 1 μm or more and 50 μm or less.

5. The light-emitting device according to any one of claims 1 to 4, wherein the joining member covers the side surface of the light-emitting element.

6. The light-emitting device according to any one of claims 1 to 4, wherein the lower surface of the light-transmitting member and the upper surface of the light-emitting element are of the same size.

7. The light-emitting device according to any one of claims 1 to 4, wherein the bonding member is polysilazane.

8. The light-emitting device according to any one of claims 1 to 4, wherein, in a top view, the joining member has an inner edge that protrudes from each side of the upper surface of the translucent member toward the center of the upper surface of the translucent member.

9. The light-emitting device according to any one of claims 1 to 4, wherein the light-transmitting member contains a phosphor capable of wavelength conversion of at least a portion of the incident light.

Images