Method for manufacturing a light-emitting device, light-emitting device

Abstract

The present invention provides a method for manufacturing a light-emitting device capable of improving brightness, and a light-emitting device itself. [Solution] The manufacturing method of this light-emitting device comprises the steps of: preparing a light-emitting element; preparing a translucent member having a lower surface area larger than the upper surface of the light-emitting element; placing an uncured first bonding member on at least a part of the outer peripheral region of the upper surface of the light-emitting element; placing an uncured second bonding member with lower viscosity than the uncured first bonding member on the upper surface of the light-emitting element exposed from the first bonding member; pressing the first bonding member and the second bonding member on the lower surface of the translucent member to spread the first bonding member and / or the second bonding member on the outer peripheral region of the lower surface of the translucent member; and curing the first bonding member and the second bonding member.

Description

[Technical Field]

[0001] This disclosure relates to a method for manufacturing a light-emitting device and to a light-emitting device. [Background technology]

[0002] A light-emitting device is known that includes a substrate, a light-emitting element mounted on the substrate, a transparent material layer placed on the light-emitting element, a plate-shaped optical layer mounted on the transparent material layer, and a reflective material layer placed around the light-emitting element and the transparent material layer. In this light-emitting device, the lower surface of the plate-shaped optical layer is larger than the upper surface of the light-emitting element, and the reflective material layer forms an inclined surface connecting the lower end of the side surface of the light-emitting element and the side surface of the plate-shaped optical layer.

[0003] A method for manufacturing such a light-emitting device includes, for example, a first step of forming an uncured transparent material layer having inclined sides between a light-emitting element and a plate-shaped optical layer, and then curing the transparent material layer; and a second step of filling a non-conductive reflective material around the transparent material layer and curing it to form a reflective material layer having inclined sides that align with the inclined sides of the transparent material layer. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2012-004303 [Overview of the Initiative] [Problems that the invention aims to solve]

[0005] This disclosure aims to provide a method for manufacturing a light-emitting device with minimal brightness unevenness, and a light-emitting device with minimal brightness unevenness. [Means for solving the problem]

[0006] A method for manufacturing a light-emitting device according to one embodiment of the present disclosure includes the steps of: preparing a light-emitting element; preparing a translucent member having a lower surface area larger than the upper surface of the light-emitting element; placing an uncured first bonding member on at least a portion of the outer peripheral region of the upper surface of the light-emitting element; placing an uncured second bonding member with lower viscosity than the uncured first bonding member on the upper surface of the light-emitting element exposed from the first bonding member; pressing the first bonding member and the second bonding member with the lower surface of the translucent member to spread the first bonding member and / or the second bonding member over the outer peripheral region of the lower surface of the translucent member; and curing the first bonding member and the second bonding member.

[0007] A light-emitting device according to one embodiment of the present disclosure includes a light-emitting element, a light-transmitting member, and a bonding member disposed between the upper surface of the light-emitting element and the lower surface of the light-transmitting member, and in contact with the entire lower surface of the light-transmitting member, wherein the bonding member contains light-scattering particles, and the bonding member located in a position that does not overlap with the light-emitting element in a top view includes a region in which the density of light-scattering particles is higher than that of the bonding member located in a position that overlaps with the light-emitting element in a top view. [Effects of the Invention]

[0008] According to one embodiment of this disclosure, a method for manufacturing a light-emitting device with less brightness unevenness, and a light-emitting device with less brightness unevenness can be provided. [Brief explanation of the drawing]

[0009] [Figure 1] This is a schematic perspective view showing the light-emitting device according to this embodiment. [Figure 2] This is a cross-sectional view along line II-II in Figure 1. [Figure 3] Figure 1 shows the light-emitting element, the bonding member, and the light-transmitting member, viewed from the top side of the light-transmitting member. [Figure 4A] This is a schematic cross-sectional view showing an example of the manufacturing process of the light-emitting device according to this embodiment. [Figure 4B] This is a schematic cross-sectional view showing an example of the manufacturing process of the light-emitting device according to this embodiment. [Figure 4C]It is a cross-sectional view schematically showing an example of a manufacturing process of a light-emitting device according to this embodiment. [Figure 4D] It is a view of the light-emitting element and the first joining member as seen from the upper surface side of the light-emitting element in FIG. 4C. [Figure 4E] It is a cross-sectional view schematically showing an example of a manufacturing process of a light-emitting device according to this embodiment. [Figure 4F] It is a view of the light-emitting element, the first joining member, and the second joining member as seen from the upper surface side of the light-emitting element in FIG. A. [Figure 4G] It is a cross-sectional view schematically showing an example of a manufacturing process of a light-emitting device according to this embodiment. [Figure 4H] It is a view of the light-emitting element, the first joining member, and the second joining member as seen from the upper surface side of the light-emitting element in FIG. 4G. [Figure 4I] It is a cross-sectional view schematically showing an example of a manufacturing process of a light-emitting device according to this embodiment. [Figure 4J] It is a cross-sectional view schematically showing an example of a manufacturing process of a light-emitting device according to this embodiment. [Figure 4K] It is a view of the light-emitting element, the first joining member, the second joining member, and the light-transmissive member as seen from the upper surface side of the light-transmissive member in FIG. 4J. [Figure 4L] It is a cross-sectional view schematically showing an example of a manufacturing process of a light-emitting device according to this embodiment. [Figure 4M] It is a cross-sectional view schematically showing an example of a manufacturing process of a light-emitting device according to this embodiment. [Figure 5] It is an example of a manufacturing process of a light-emitting device according to Modification 1 of this embodiment, and is a schematic view of the light-emitting element, the first joining member, and the second joining member as seen from the upper surface side of the light-emitting element. [Figure 6A] It is a cross-sectional view schematically showing an example of a manufacturing process of a light-emitting device according to Modification 2 of this embodiment. [Figure 6B] It is a view of the light-emitting element, the first joining member, the second joining member, and the light-transmissive member as seen from the upper surface side of the light-transmissive member in FIG. 6A. [Figure 7A]This is a schematic diagram showing an example of the manufacturing process of a light-emitting device according to Modification 3 of this embodiment, with the light-emitting element, the first bonding member, and the second bonding member viewed from the top side of the light-emitting element. [Figure 7B] This is a schematic diagram showing an example of the manufacturing process of a light-emitting device according to Modification 3 of this embodiment, with the light-emitting element, the first bonding member, and the second bonding member viewed from the top side of the light-emitting element. [Figure 7C] This is a schematic diagram showing an example of the manufacturing process of a light-emitting device according to Modification 3 of this embodiment, with the light-emitting element, the first bonding member, and the second bonding member viewed from the top side of the light-emitting element. [Modes for carrying out the invention]

[0010] Hereinafter, a manufacturing method of an embodiment of the present invention and a light-emitting device obtained by the manufacturing method (hereinafter sometimes referred to as the "light-emitting device according to the embodiment") will be described with reference to the drawings. In the following description, terms indicating specific directions or positions (for example, "up," "down," and other terms including these terms) will be used as needed. However, the use of these terms is for the purpose of facilitating the understanding of the invention with reference to the drawings, and the technical scope of the present invention is not limited by the meaning of these terms. Furthermore, the same reference numerals appearing in multiple drawings indicate the same or equivalent parts or components.

[0011] Furthermore, the embodiments shown below are illustrative examples of light-emitting devices and the like that embody the technical concept of the present invention, and do not limit the present invention to the following. Also, the dimensions, materials, shapes, relative arrangements, etc. of the components described below are intended to be illustrative, and are not intended to limit the scope of the present invention to those specific examples unless otherwise stated. In addition, the content described in one embodiment is applicable to other embodiments and modifications. Furthermore, the size and positional relationships of the members shown in the drawings may be exaggerated in order to clarify the explanation. In addition, in order to avoid the drawings becoming excessively complex, schematic diagrams that omit the illustration of some elements may be used, or end view diagrams that show only the cut surface may be used as cross-sectional views. Furthermore, even if the size or shape of some members changes due to processing or pressing, the same name may be used in the explanation.

[0012] <Light-emitting device 1 according to this embodiment> Figure 1 is a schematic perspective view of the light-emitting device according to this embodiment. Figure 2 is a cross-sectional view taken along line II-II in Figure 1. Figure 2 shows a cross-section of the light-emitting device 1 taken by a plane perpendicular to the upper surface 20a of the light-emitting element 20. The same applies to subsequent cross-sectional views.

[0013] In each drawing, for reference, mutually orthogonal X, Y, and Z axes are shown as needed. The direction parallel to the X axis is called the first direction X, the direction parallel to the Y axis is called the second direction Y, and the direction parallel to the Z axis is called the third direction Z. Furthermore, in the first direction X, the direction the arrow is pointing is called the +X direction, and the opposite direction of the +X direction is called the -X direction. In the second direction Y, the direction the arrow is pointing is called the +Y direction, and the opposite direction of the +Y direction is called the -Y direction. In the third direction Z, the direction the arrow is pointing is called the +Z direction, and the opposite direction of the +Z direction is called the -Z direction. However, these do not restrict the orientation of the light-emitting device when it is in use, and the orientation of the light-emitting device when in use is arbitrary. Also, viewing an object from the +Z direction toward the -Z direction is called a top view.

[0014] As shown in Figures 1 and 2, the light-emitting device 1 includes a wiring board 10, a light-emitting element 20, a protective element 30, a bonding member 40, a light-transmitting member 50, and a covering member 60. However, the light-emitting device 1 may also be configured without the protective element 30 and the wiring board 10.

[0015] In the light-emitting device 1, the light-emitting element 20 is arranged on the wiring board 10. Furthermore, the light-emitting device 1 may have a protective element 30 arranged on the wiring board 10. The light-emitting element 20 has an upper surface 20a, a plurality of side surfaces 20c connected to the upper surface 20a, and a lower surface 20b opposite to the upper surface 20a. The plurality of side surfaces 20c are connected to the upper surface 20a and the lower surface 20b. In other words, each of the plurality of side surfaces 20c has an outer edge connected to 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.

[0016] 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.

[0017] The joining member 40 is positioned between the upper surface 20a of the light-emitting element 20 and the lower surface 50b of the light-transmitting member 50. The joining member 40 covers at least a portion of the side surfaces 20c of the light-emitting element 20 and the upper surface 20a. Specifically, the joining member 40 covers the entire upper surface 20a of the light-emitting element 20 and 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. The joining member 40 has side surfaces 40c that connect to the side surfaces 20c of the light-emitting element 20 and the lower surface 50b of the light-transmitting member 50. 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 that it covers substantially all of each side surface 20c. In other words, it is preferable that the side surface 40c of the joining member 40 contacts the side surface 20c of each side surface 20c of the light-emitting element 20 at a position close to the lower end (i.e., the side connected to the lower surface 20b), and it is more preferable that it contacts the lower end of each side surface 20c. Specifically, it is preferable that the joining member 40 covers an area of ​​75% to 100% in the height direction from the upper end of each side surface 20c of the light-emitting element 20, and it is more preferable that the joining member 40 covers an area of ​​90% to 100%.

[0018] The bonding member 40 is translucent to light emitted from the light-emitting element 20. Light emitted from the light-emitting element 20 enters the translucent member 50 via the bonding member 40 and exits to the outside via the translucent member 50. The bonding member 40 contains light-scattering particles as an additive. By having the bonding member 40 containing the 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.

[0019] Figure 3 shows the light-emitting element, bonding member, and light-transmitting member of the light-emitting device 1, viewed from the top side of the light-transmitting member. In the bonding member 40 shown in Figure 3, areas with a relatively high density of light-scattering particles are indicated by a dark dot pattern, and areas with a relatively low density of light-scattering particles are indicated by a light dot pattern. In other figures as well, the high and low densities of light-scattering particles in the bonding member 40 may be indicated by a similar dot pattern.

[0020] As shown in Figure 3, the bonding member 40 located in a position that does not overlap with the light-emitting element 20 in a top view (i.e., outside the light-emitting element 20) includes a region 40h with a higher concentration of light-scattering particles than the bonding member 40 located in a position that overlaps with the light-emitting element 20 in a top view. That is, the proportion of the weight of the bonding member 40 located in a position that does not overlap with the light-emitting element 20 in a top view that is accounted for by light-scattering particles is higher than the proportion of the weight of the bonding member 40 located in a position that overlaps with the light-emitting element 20 in a top view that is accounted for by light-scattering particles. The region 40h with a high concentration of light-scattering particles in the bonding member 40 may include a portion that is positioned in contact with the outer edge of the upper surface 20a of the light-emitting element 20 in a top view. Figure 3 shows an example where the region 40h is positioned in contact with the outer edge of the upper surface 20a of the light-emitting element 20 in a top view and along the outside of the four corners, but the position where the region 40h is positioned is not limited to this. It is preferable that there is no clear interface between the region 40h and the surrounding region.

[0021] As shown in Figures 1 and 2, 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 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 a surface that is not parallel to the lower surface 50b. It is preferable that the light-transmitting member 50 has a lower surface 50b with a larger area than the upper surface 20a of the light-emitting element 20. It is also preferable that the light-transmitting member 50 is positioned such that, when viewed from above, the lower surface 50b of the light-transmitting member 50 encloses the light-emitting element 20. Furthermore, in the light-emitting device 1, it is preferable that the joining member 40 interposed between the lower surface 50b of the light-transmitting member 50 and the upper surface 20a of the light-emitting element 20 is in contact with the entire lower surface 50b of the light-transmitting member 50. That is, in the light-emitting device 1, it is preferable that the joining member 40 is positioned to reach the entire outer edge including the four corners of the rectangular lower surface 50b of the light-transmitting member 50, and that the entire lower surface 50b is covered by the joining member 40.

[0023] For example, if there is an area exposed from the joining member 40 at the corner of the rectangular lower surface 50b of the translucent member 50, light emitted from the light-emitting element 20 is less likely to enter that area. As a result, the brightness decreases at the corner of the upper surface 50a of the translucent member 50, and brightness unevenness may occur on the light-emitting surface of the light-emitting device 1 (i.e., the upper surface of the translucent member 50). On the other hand, in the light-emitting device 1, since the joining member 40 is in contact with the entire lower surface 50b of the translucent member 50, more of the light emitted from the light-emitting element 20 can be incident on the lower surface 50b of the translucent member 50 via the joining member 40. As a result, the decrease in brightness at the corner of the upper surface 50a of the translucent member 50 is reduced, and a light-emitting device 1 with less brightness unevenness can be realized.

[0024] 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 and the side surface 50c of the light-transmitting member 50. The covering member 60 further covers the upper surface of the wiring board 10. If 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. The covering member 60 may also cover the lower surface 20b of the light-emitting element 20. Furthermore, if a part of the side surface 20c of the light-emitting element 20 is exposed from the joining member 40, the covering member 60 may directly cover the side surface 20c of the light-emitting element 20 that is exposed from the joining member 40.

[0025] 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.

[0026] 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.

[0027] 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.

[0028] 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.

[0029] 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 the side surface 50c of the light-transmitting member 50 and 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.

[0030] 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 be, for example, flush. Also, the upper surface of the second covering member 62 and the upper surface 50a of the light-transmitting member 50 can be, for example, flush.

[0031] 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. Furthermore, of the light emitted by the light-emitting element 20, the light that travels laterally is reflected at the interface between the side surface 20c of the bonding member 40 and the covering member 60 and taken out of the light-emitting device 1 via the bonding member 40 and the translucent member 50.

[0032] The following describes in detail each element constituting the light-emitting device 1 according to the embodiment.

[0033] [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 base material 11 is, for example, substantially rectangular parallelepiped or substantially cubic in 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 of metals 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.

[0034] 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.

[0035] 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.

[0036] 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.

[0037] 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 those that have been processed into a predetermined shape using the aforementioned metal or alloy by rolling, punching, extrusion, etching by wet or dry etching, or a combination thereof.

[0038] (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.

[0039] 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-y The 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.

[0040] 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.

[0041] 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.

[0042] (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.

[0043] (Jointing member 40) The bonding member 40 is positioned between the light-emitting element 20 and the light-transmitting member 50, and bonds the light-emitting element 20 and the light-transmitting member 50. As described above, the bonding member 40 is light-transmitting and guides the light emitted from the light-emitting element 20 to the light-transmitting member 50. By covering the side surface 20c of the light-emitting element 20 with the bonding member 40, it becomes easier to guide the light emitted from the side surface 20c of the light-emitting element 20 to the light-transmitting member 50, thereby improving the light extraction efficiency in the light-emitting device 1.

[0044] The bonding member 40 is positioned to cover the upper surface 20a and each of the side surfaces 20c of the light-emitting element 20. 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. Phenylmethyl silicone resin has a higher refractive index than dimethyl silicone resin, which can improve the light extraction efficiency of the light-emitting device 1. Alternatively, a silicon alcoholate such as polysilazane, which has better heat resistance, may be used as the bonding member 40.

[0045] 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, and its value shall be determined by the air permeability method or FSSSNo (Fisher-SubSieve-Sizers-No.) (a value represented by a so-called D bar (a bar above the D)). The shape of the light-scattering particles may be spherical, irregularly shaped and fragmented, needle-shaped, columnar, plate-shaped (including flaky), fibrous, or dendritic (the same applies to light-reflecting materials and / or phosphors described later). The light-scattering particles may also be hollow or porous.

[0046] (Translucent member 50) The light-transmitting member 50 is disposed on the light-emitting element 20 and transmits the light emitted from the light-emitting element 20 to the outside. The light-transmitting member 50 includes those that transmit 60% or more of the light from the light-emitting element 20 and / or the light whose wavelength has been converted from the light from the light-emitting element 20 (for example, light in the range of 320 nm to 850 nm), and those that transmit 70% or more of the light are preferred. The light-transmitting member 50 may be formed of, for example, an inorganic material such as glass, ceramic, sapphire, etc., a resin containing one or more of silicone resin, modified silicone resin, epoxy resin, modified epoxy resin, acrylic resin, phenol resin, fluororesin, or an organic material such as a hybrid resin. The light-transmitting member 50 may contain a phosphor capable of wavelength-converting at least a part of the incident light. Examples of the light-transmitting member 50 containing a phosphor include a sintered body of a phosphor and those obtained by incorporating phosphor powder into the above-described materials. Further, the light-transmitting member 50 may be one in which a phosphor layer such as a resin layer containing a phosphor or a glass layer containing a phosphor is disposed on the surface of a light-transmitting plate which is a molded body of resin, glass, ceramic, etc. Further, the light-transmitting member 50 may contain a filler such as a light-scattering particle according to the purpose. Further, when containing a filler such as a light-scattering particle, the light-transmitting member 50 may be one obtained by incorporating a filler into resin, glass, ceramic or other inorganic substances, or one in which a light-scattering layer such as a resin layer containing a light-scattering particle or a glass layer containing a light-scattering particle is disposed on the surface of a light-transmitting plate which is a molded body of resin, glass, ceramic, etc.

[0047] Examples of the phosphor include yttrium aluminum garnet-based phosphors (for example, (Y,Gd)3(Al,Ga)5O 12 :Ce), lutetium aluminum garnet-based phosphors (for example, Lu3(Al,Ga)5O 12 :Ce), terbium aluminum garnet-based phosphors (for example, Tb3(Al,Ga)5O 12 :Ce), CCA-based phosphors (for example, Ca 10 (PO4)6Cl2:Eu), SAE-based phosphors (for example, Sr4Al 14 O 25 :Eu), chlorosilicate-based phosphors (for example, Ca8MgSi4O16 (Cl2:Eu), silicate phosphors (e.g., (Ba,Sr,Ca,Mg)2SiO4:Eu), β-sialon phosphors (e.g., (Si,Al)3(O,N)4:Eu) or α-sialon phosphors (e.g., Ca(Si,Al) 12 (O,N) 16 :Eu), etc. oxynitride phosphors, LSN phosphors (e.g., (La,Y)3Si6N 11 :Ce), BSESN phosphors (e.g., (Ba,Sr)2Si5N8:Eu), SLA phosphors (e.g., SrLiAl3N4:Eu), CASN phosphors (e.g., CaAlSiN3:Eu) or SCASN phosphors (e.g., (Sr,Ca)AlSiN3:Eu), etc. nitride phosphors, KSF phosphors (e.g., K2SiF6:Mn), KSAF phosphors (e.g., K2(Si 1-x Al x )F 6-x :Mn where x satisfies 0 < x < 1), or fluoride phosphors such as MGF phosphors (e.g., 3.5MgO·0.5MgF2·GeO2:Mn), quantum dots having a perovskite structure (e.g., (Cs,FA,MA)(Pb,Sn)(F,Cl,Br,I)3 where FA and MA represent formamidinium and methylammonium, respectively), II-VI group quantum dots (e.g., CdSe), III-V group quantum dots (e.g., InP), or quantum dots having a chalcopyrite structure (e.g., (Ag,Cu)(In,Ga)(S,Se)2), etc. can be used.

[0048] As the light scattering particles, the same particles as those used in the joining member 40 can be used.

[0049] When a resin is used as the binder of the phosphor layer or the light scattering layer, examples of the resin include thermosetting resins such as epoxy resins, modified epoxy resins, silicone resins, modified silicone resins, etc.

[0050] Furthermore, in order to improve light extraction, the light-transmitting member 50 may have an optical thin film such as an anti-reflective film on its upper and / or lower surface, and may also have an optical film such as a reflective film on its side surface.

[0051] (Covering member 60) The covering member 60 is a member that exposes the upper surface 50a of the light-transmitting member 50 and covers the side surface 40c of the joining member 40 and the side surface 50c of the light-transmitting member 50. 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.

[0052] 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.

[0053] 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 above-mentioned materials exemplified as materials for the covering member 60. By composing the covering member 60 from a first covering member 61 and a second covering member 62, for example, it becomes possible to use a material with high mechanical strength for the second covering member 62 that constitutes the outer surface of the light-emitting device 1, or to use a material with low elasticity and / or low linear expansion for the first covering member 61 that covers the lower surface 20b of the light-emitting element 20, thereby mitigating the stress of resin expansion.

[0054] <Manufacturing method for a light-emitting device according to an embodiment> A method for manufacturing a light-emitting device according to an embodiment includes the steps of: preparing a light-emitting element; preparing a translucent member having a lower surface area larger than the upper surface of the light-emitting element; placing an uncured first bonding member on at least a part of the outer peripheral region of the upper surface of the light-emitting element; placing an uncured second bonding member with lower viscosity than the uncured first bonding member on the upper surface of the light-emitting element exposed from the first bonding member; pressing the first bonding member and the second bonding member with the lower surface of the translucent member to spread the first bonding member and / or the second bonding member over the outer peripheral region of the lower surface of the translucent member; and curing the first bonding member and the second bonding member.

[0055] The following describes each manufacturing step of the method for manufacturing the light-emitting device according to the embodiment, with reference to the drawings.

[0056] Figures 4A to 4M are schematic diagrams illustrating the manufacturing process of the light-emitting device according to this embodiment. Specifically, Figures 4A, 4B, 4C, 4E, 4G, 4I, 4J, 4L, and 4M are schematic cross-sectional views showing an example of the manufacturing process of the light-emitting device according to this embodiment. Figures 4D, 4F, and 4H are views of the light-emitting element, the first bonding member, and the second bonding member as seen from the top side of the light-emitting element. Figure 4K is a view of the light-emitting element, the first bonding member, the second bonding member, and the translucent member as seen from the top side of the translucent member.

[0057] (Process for preparing the light-emitting element) First, as shown in Figure 4A, 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.

[0058] (Process of preparing the wiring board, process of arranging light-emitting elements on the wiring board) Next, as shown in Figure 4B, 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.

[0059] (Step of positioning the first joining member) Next, as shown in Figures 4C and 4D, an uncured first bonding member 401 is placed on at least a portion of the outer peripheral region of the upper surface 20a of the light-emitting element 20. The uncured first bonding member 401 hardens together with the second bonding member, which will be described later, to form a bonding member 40 that joins the light-transmitting member 50 and the light-emitting element 20 in the light-emitting device 1. The first bonding member 401 can be made from the material described above. The viscosity of the uncured first bonding member 401 can be, for example, 30 Pa·s or more and 120 Pa·s or less. The outer peripheral region of the upper surface 20a is a region having a certain width from the outer edge of the upper surface 20a. The certain width can be, for example, about 1 / 3 of the length of one side of the upper surface 20a.

[0060] Here, as an example, we will describe a case where the upper surface 20a of the light-emitting element 20 is rectangular, and uncured first bonding members 401 are arranged at the four corners of the upper surface 20a of the light-emitting element 20 so as to be spaced apart from each other.

[0061] First, the nozzle is positioned above one corner of the upper surface 20a of the light-emitting element 20, and the uncured first bonding member 401 is dispensed from the nozzle. After a predetermined amount of the first bonding member 401 has been dispensed, the dispensing is stopped, and the nozzle is moved above another corner of the outer peripheral region of the upper surface 20a of the light-emitting element 20, and the uncured first bonding member 401 is dispensed from the nozzle. This operation is repeated until the uncured first bonding member 401 has been dispensed to all four corners of the rectangle, and then the nozzle is moved away from above the light-emitting element 20. Note that the uncured first bonding member 401 may be applied to multiple corners simultaneously using a multi-nozzle capable of simultaneous multi-point dispensing in a single discharge.

[0062] The uncured first 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 first bonding member 401, due to surface tension, takes on a hemispherical shape, circular in top view and semi-circular in side view, as shown in Figures 4C and 4D. 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. Operations to promote the curing reaction include 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.

[0063] Alternatively, the uncured first bonding member 401 may be arranged in a frame shape around the outer peripheral region of the upper surface 20a of the light-emitting element 20. When arranging the uncured first bonding member 401 in a frame shape, the nozzle should be moved above the outer peripheral region of the upper surface 20a of the light-emitting element 20 while discharging the uncured first bonding member 401 from the nozzle.

[0064] (Step of positioning the second joining member) Next, as shown in Figures 4E and 4F, an uncured second bonding member 402 with a lower viscosity than the uncured first bonding member 401 is placed on the upper surface 20a of the light-emitting element 20 exposed from the first bonding member 401. The second bonding member 402 can use the same material as the bonding member 40 described above. Furthermore, it is preferable that the first bonding member 401 and the second bonding member 402 use the same resin material as the base material. The viscosity of the uncured second bonding member 402 can be, for example, 0.1 Pa·s or more and 15 Pa·s or less.

[0065] Here, as an example, we will describe a case in which an uncured second bonding member 402 is placed in the central region located inside the outer peripheral region of the upper surface 20a of the light-emitting element 20.

[0066] First, the nozzle is positioned above the central region of the upper surface 20a of the light-emitting element 20, and the uncured second bonding member 402 is discharged from the nozzle. Once a predetermined amount of the second bonding member 402 has been discharged, the discharge is stopped, and the nozzle is moved away from above the light-emitting element 20.

[0067] Because the uncured first bonding member 401 has high viscosity, in the process shown in Figures 4E and 4F it maintains almost the same shape as in the process shown in Figures 4C and 4D. In contrast, because the uncured second bonding member 402 has low viscosity, it spreads outwards from the discharge point and reaches the four first bonding members 401. Once the second bonding member 402 reaches each of the first bonding members 401, it spreads further along the first bonding member 401 and eventually spreads across the entire upper surface 20a, as shown in Figures 4G and 4H. The second bonding member 402 may crawl up to the bottom of the first bonding member 401 or crawl up to the entire surface of the first bonding member 401.

[0068] Furthermore, if the uncured second bonding member 402 is dispensed without the uncured first bonding member 401 being placed, the uncured second bonding member 402 will spread concentrically while maintaining the smallest possible area due to surface tension, making it difficult to reach the rectangular corners of the upper surface 20a of the light-emitting element 20. In contrast, if the uncured second bonding member 402 is placed with the uncured first bonding member 401 in place in the outer peripheral region of the upper surface of the light-emitting element 20, the uncured second bonding member 402 will come into contact with the first bonding member 401 and, starting from the contact point with the first bonding member 401, will spread along the upper surface 20a along the first bonding member 401 using capillary action, making it easier to reach the corners of the upper surface 20a.

[0069] In the step of placing the second bonding member 402, it is preferable that the volume of the uncured second bonding member 402 placed on the light-emitting element 20 is larger than the volume of the uncured first bonding member 401 placed on the light-emitting element 20 in the step of placing the first bonding member 401. The light transmittance when the uncured first bonding member 401 and the uncured second bonding member 402 are cured increases as the viscosity decreases. By making the volume of the uncured second bonding member 402, which has low viscosity, larger than the volume of the uncured first bonding member 401, the proportion of the area occupied by the cured uncured second bonding member 402 in the cured bonding member 40 becomes larger than the proportion occupied by the cured uncured first bonding member 401, thus increasing the light transmittance.

[0070] Furthermore, if the viscosity of the uncured second bonding member 402 exceeds 15 Pa·s, surface tension will act and it will be difficult to spread, so it is preferable that the viscosity of the uncured second bonding member 402 be 15 Pa·s or less.

[0071] The viscosity of the uncured first bonding member 401 and the uncured second bonding member 402 can be adjusted by the physical properties of the base material such as the selected resin, or by adding a viscosity-adjusting filler (for example, nanoparticles such as the light-scattering particles mentioned above) to the base material.

[0072] In this embodiment, the uncured first bonding member 401 and the uncured second bonding member 402 are based on a resin material and each contains light-scattering particles. In this case, the viscosity of the uncured first bonding member 401 and the uncured second bonding member 402 can be adjusted by the amount of light-scattering particles they contain. Specifically, the higher the concentration of light-scattering particles in the uncured bonding member, the higher the viscosity. Furthermore, even at the same concentration, the smaller the particle size, the higher the viscosity can be.

[0073] (Process of preparing light-transmitting material) Next, as shown in Figure 4I, a translucent member 50 is prepared, having a lower surface 50b with an area larger than the upper surface 20a of the light-emitting element 20. Then, the translucent member 50 is placed on the upper surface 20a of the light-emitting element 20 via an uncured first bonding member 401. The lower surface 50b of the translucent member 50 is in contact with the uncured first bonding member 401. The uncured second bonding member 402 may or may not be in contact with the lower surface 50b of the translucent member 50.

[0074] Because the uncured first bonding member 401 has high viscosity, the process shown in Figure 4I maintains almost the same shape as the processes shown in Figures 4G and 4H. Therefore, the translucent member 50 is easily held in place by the surface tension of the first bonding member 401 and is less likely to move in the first direction X or the second direction Y, or rotate in the XY plane. In other words, by placing the translucent member 50 on the highly viscous first bonding member 401, the misalignment of the translucent member 50 with respect to the upper surface 20a of the light-emitting element 20 can be reduced.

[0075] Furthermore, if the viscosity of the uncured first bonding member 401 falls below 25 Pa·s, the surface tension decreases, making it easier for the translucent member 50 to rotate in the XY plane. Therefore, it is preferable that the viscosity of the uncured first bonding member 401 be 30 Pa·s or higher. On the other hand, if the viscosity of the uncured first bonding member 401 exceeds 120 Pa·s, it becomes difficult for the uncured first bonding member 401 to deform when pressed by the translucent member 50. Therefore, it is preferable that the viscosity of the uncured first bonding member 401 be 120 Pa·s or lower.

[0076] As mentioned above, the light transmittance of the uncured first bonding member 401 when it has cured increases as the viscosity of the uncured first bonding member 401 decreases. Therefore, considering light transmittance, the viscosity of the uncured first bonding member 401 is more preferably 30 Pa·s or more and 70 Pa·s or less, and even more preferably 30 Pa·s or more and 50 Pa·s or less.

[0077] (Steps to spread the first and / or second joining members, and to harden them) Next, the first joining member 401 and the second joining member 402 shown in Figure 4I are pressed against the lower surface 50b of the translucent member 50 in the direction of the arrow, and as shown in Figure 4J, the first joining member 401 and / or the second joining member 402 are spread out over the outer peripheral region of the lower surface 50b of the translucent member 50. Here, the joining member in which the first joining member 401 and the second joining member 402 are mixed is indicated by reference numeral 40. It is preferable that no clear interface is formed between the first joining member 401 and the second joining member 402 after curing. Here, silicone resin is used as the base material for the first joining member 401 and the second joining member 402, and by bringing them into contact with each other in an uncured state and curing them, a joining member 40 is obtained in which the first joining member 401 and the second joining member 402 are integrated (i.e., there is no interface between the first joining member 401 and the second joining member 402).

[0078] When the lower surface 50b of the translucent member 50 presses against the first joining member 401, the first joining member 401 begins to move between the lower surface 50b of the translucent member 50 and the upper surface 20a of the light-emitting element 20. Subsequently, when the lower surface 50b of the translucent member 50 comes into contact with the second joining member 402 and presses against the second joining member 402, the second joining member 402, which is located between the lower surface 50b of the translucent member 50 and the upper surface 20a of the light-emitting element 20, expands outward. As a result, as shown in Figure 4K, for example, the second joining member 402 is positioned with a substantially constant thickness across the entire region sandwiched between the upper surface 20a of the light-emitting element 20 and the lower surface 50b of the translucent member 50.

[0079] Furthermore, between the lower surface 50b of the light-transmitting member 50 and the upper surface 20a of the light-emitting element 20, the second joining member 402 expands so as to push the first joining member 401 outward from the upper surface 20a of the light-emitting element 20. Therefore, as shown in Figure 4K, for example, in a top view, the first joining member 401 is positioned so as to be in contact with the outer edge of the upper surface 20a of the light-emitting element 20 at the four corners of the upper surface 20a of the light-emitting element 20. In addition, the first joining member 401 and / or the second joining member 402 cover part or all of the side surface 20c of the light-emitting element 20. Note that a part of the first joining member 401 may remain in the region sandwiched between the upper surface 20a of the light-emitting element 20 and the lower surface 50b of the light-transmitting member 50 (i.e., the region where the light-emitting element 20 and the light-transmitting member 50 overlap in a plan view).

[0080] Furthermore, in areas not sandwiched between the upper surface 20a of the light-emitting element 20 and the lower surface 50b of the light-transmitting member 50, the first bonding member 401 and the second bonding member 402 are not pressed against the lower surface 50b of the light-transmitting member 50. Therefore, the first bonding member 401, which has high viscosity, does not easily reach the outer periphery of the lower surface 50b of the light-transmitting member 50, including the corners. On the other hand, the second bonding member 402, which has low viscosity, tends to spread along the first bonding member 401 even in areas not sandwiched between the upper surface 20a of the light-emitting element 20 and the lower surface 50b of the light-transmitting member 50. Therefore, as shown in Figure 4K, the outer periphery of the lower surface 50b of the light-transmitting member 50, including the corners, is easily in contact with the second bonding member 402.

[0081] Subsequently, the first joining member 401 and the second joining member 402 are cured. By curing the first joining member 401 and the second joining member 402 simultaneously, a joint member 40 is formed in which the first joining member 401 and the second joining member 402 are integrated, and the translucent member 50 and the light-emitting element 20 are joined via the joint member 40. Curing can be carried out by known methods, such as heating in an oven.

[0082] By simultaneously curing the uncured first bonding member 401 and the uncured second bonding member 402, a bonding member 40 without an interface can be formed. This improves the mechanical strength of the bonding member 40. In addition, the light emitted from the light-emitting element 20 can be efficiently guided to the light-transmitting member 50.

[0083] 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.

[0084] (Step of arranging the first covering member) Next, as shown in Figure 4L, 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.

[0085] (Step of placing the second covering member) Next, as shown in Figure 4M, a second covering member 62 is placed to expose the upper surface 50a of the light-transmitting member 50 and cover the side surface 50c of the light-transmitting member 50 and 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 50c of the light-transmitting member 50 and 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 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.

[0086] Before placing the light-emitting element 20 on the wiring board 10, the light-transmitting member 50 may be placed on the upper surface 20a of the light-emitting element 20 via the first bonding member 401 and the second bonding member 402, and the first bonding member 401 and the second bonding member 402 may be cured. Then, this structure may be placed on the wiring board 10.

[0087] 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.

[0088] In this method for manufacturing the light-emitting device 1, an uncured first bonding member 401 is placed on at least a portion of the outer peripheral region of the upper surface 20a of the light-emitting element 20, and an uncured second bonding member 402, which has a lower viscosity than the uncured first bonding member 401, is placed on the upper surface 20a of the light-emitting element 20 that is exposed from the first bonding member 401. Then, the first bonding member 401 and the second bonding member 402 are pressed against the lower surface 50b of the light-transmitting member 50, spreading the first bonding member 401 and / or the second bonding member 402 over the outer peripheral region of the lower surface 50b of the light-transmitting member 50. As a result, the low-viscosity second bonding member 402 spreads along the high-viscosity first bonding member 401 so as to come into contact with the corners of the lower surface 50b of the light-transmitting member 50. As a result, since the hardened bonding member 40 is in contact with the entire lower surface 50b of the light-transmitting member 50, the brightness is less likely to decrease at the corners of the lower surface 50b of the light-transmitting member 50, and a light-emitting device 1 with less brightness unevenness can be manufactured.

[0089] <Variation> Figure 5 is a schematic diagram illustrating the manufacturing process of a light-emitting device according to Modification 1 of this embodiment. Specifically, Figure 5 shows the light-emitting element, the first bonding member, and the second bonding member viewed from the top side of the light-emitting element. In the manufacturing process of the light-emitting device according to this embodiment, the process shown in Figure 5 may be performed instead of the process shown in Figure 4F.

[0090] In the step of arranging the second bonding member shown in Figure 4F, an example was described in which one uncured second bonding member 402 is placed in the central region located inside the outer peripheral region of the upper surface 20a of the light-emitting element 20. However, the example is not limited to this, and as shown in Figure 5, in the step of arranging the second bonding member, the uncured second bonding member 402 may also be placed in the outer peripheral region of the upper surface 20a of the light-emitting element 20 and in the central region surrounded by the outer peripheral region. In the example in Figure 5, in addition to the central region, one uncured second bonding member 402 is placed between each of the adjacent corners of the outer peripheral region.

[0091] In this way, by placing the uncured second bonding member 402 in both the outer peripheral region and the central region of the upper surface 20a of the light-emitting element 20, the second bonding member 402 can be more reliably brought into contact with the corner of the lower surface 50b of the light-transmitting member 50 during the process of spreading the first bonding member and / or the second bonding member shown in Figures 4J and 4K.

[0092] Figures 6A and 6B are schematic diagrams illustrating the manufacturing process of a light-emitting device according to Modification 2 of this embodiment. Specifically, Figure 6A is a schematic cross-sectional view showing an example of the manufacturing process of a light-emitting device according to Modification 2 of this embodiment. Figure 6B is a view of the light-emitting element, the first bonding member, the second bonding member, and the light-transmitting member, seen from the top side of the light-transmitting member.

[0093] If the lower surface 50b of the translucent member 50 is rectangular, the steps shown in Figures 6A and 6B may be performed before the step of spreading the first and / or second joining member. In the steps shown in Figures 6A and 6B, uncured third joining members 403, which have a higher viscosity than the uncured second joining member 402, are placed at the four corners of the lower surface 50b of the translucent member 50. It is preferable to select an uncured third joining member 403 with a high viscosity so that it does not easily crawl up onto the side surface 50c of the translucent member 50. The viscosity of the uncured third joining member 403 can be, for example, 100 Pa·s or more and 450 Pa·s or less.

[0094] After the steps shown in Figures 6A and 6B, the light-emitting device is completed by performing the same steps as in Figures 4J to 4M.

[0095] Thus, in the manufacturing process of the light-emitting device according to Modification 2 of this embodiment, the uncured third bonding member 403 is placed at the four corners of the lower surface 50b of the light-transmitting member 50 before the step of spreading the first bonding member and / or the second bonding member. As a result, in the step of spreading the first bonding member and / or the second bonding member, the second bonding member 402 that has reached the third bonding member 403 spreads further along the third bonding member 403, making it easier to reach the outer periphery of the lower surface 50b of the light-transmitting member 50, including the corners. This is particularly effective when there is a large difference in area between the lower surface 50b of the light-transmitting member 50 and the upper surface 20a of the light-emitting element 20.

[0096] The uncured third joining member 403 may be cured before the step of spreading the first joining member 401 and / or the second joining member 402, or it may be cured after the step of spreading the first joining member 401 and / or the second joining member 402, at the same time as the first joining member 401 and the second joining member 402.

[0097] Figures 7A to 7C are schematic diagrams illustrating the manufacturing process of a light-emitting device according to Modification 3 of this embodiment. Specifically, Figures 7A to 7C show the light-emitting element, the first bonding member, and the second bonding member as viewed from the top surface of the light-emitting element. Figures 7A to 7C illustrate the positions for arranging the uncured first bonding member 401 and the uncured second bonding member 402 when the top surface 20a of the light-emitting element 20 is rectangular.

[0098] First, after performing the same steps as in Figures 4A and 4B, the uncured first bonding member 401 is placed on at least a portion of the outer peripheral region of the upper surface 20a of the light-emitting element 20, as shown in Figure 7A. If the upper surface 20a of the light-emitting element 20 is rectangular, for example, the uncured first bonding member 401 can be placed in two regions near the short side of the upper surface 20a of the light-emitting element 20, spaced apart from each other.

[0099] Next, as shown in Figure 7B, an uncured second bonding member 402 with a lower viscosity than the uncured first bonding member 401 is placed on the upper surface 20a of the light-emitting element 20 that is exposed from the first bonding member 401. For example, the uncured second bonding member 402 is placed in the central region sandwiched between the opposing first bonding members 401, so as not to come into contact with the first bonding member 401.

[0100] Because the uncured second bonding member 402 has low viscosity, it spreads outwards from the discharge point and reaches the two first bonding members 401. Once the second bonding member 402 reaches the first bonding member 401, it spreads further along the first bonding member 401 and eventually spreads across the entire upper surface 20a, as shown in Figure 7C. The second bonding member 402 may creep up to the bottom of the first bonding member 401 or to the entire surface of the first bonding member 401.

[0101] After the process shown in Figure 7C, the light-emitting device is completed by performing the same process as in Figures 4I to 4M. Thus, the method for manufacturing a light-emitting device according to this disclosure is also applicable to light-emitting devices with a rectangular top surface.

[0102] 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.

[0103] In addition to the embodiments described above, the following further notes are disclosed. (Note 1) The process of preparing the light-emitting element, A step of preparing a light-transmitting member having a lower surface area larger than the upper surface of the light-emitting element, The steps include: placing an uncured first bonding member on at least a portion of the outer peripheral region of the upper surface of the light-emitting element; A step of placing an uncured second bonding member, which has a lower viscosity than the uncured first bonding member, on the upper surface of the light-emitting element exposed from the first bonding member, The steps include pressing the first joining member and the second joining member against the lower surface of the light-transmitting member and spreading the first joining member and / or the second joining member over the outer peripheral region of the lower surface of the light-transmitting member, A method for manufacturing a light-emitting device, comprising the steps of curing the first joining member and the second joining member. (Note 2) The upper surface of the light-emitting element is rectangular. The method for manufacturing a light-emitting device according to Appendix 1, wherein in the step of arranging the first bonding member, uncured first bonding members are arranged at the four corners of the upper surface of the light-emitting element so as to be spaced apart from each other. (Note 3) The method for manufacturing a light-emitting device according to Appendix 2, wherein in the step of arranging the second bonding member, an uncured second bonding member is placed in the central region located inside the outer peripheral region of the upper surface of the light-emitting element. (Note 4) The method for manufacturing a light-emitting device according to Appendix 2, wherein in the step of arranging the second bonding member, the uncured second bonding member is arranged in the outer peripheral region of the upper surface of the light-emitting element and in the central region surrounded by the outer peripheral region of the upper surface of the light-emitting element. (Note 5) The method for manufacturing a light-emitting device according to any one of the appendices 1 to 4, wherein the viscosity of the uncured first bonding member is 30 Pa·s or more and 120 Pa·s or less. (Note 6) The method for manufacturing a light-emitting device according to any one of Appendix 1 to 5, wherein the viscosity of the uncured second bonding member is 0.1 Pa·s or more and 15 Pa·s or less. (Note 7) A method for manufacturing a light-emitting device according to any one of Appendix 1 to 6, wherein the volume of the uncured second bonding member placed on the light-emitting element in the step of placing the second bonding member is greater than the volume of the uncured first bonding member placed on the light-emitting element in the step of placing the first bonding member. (Note 8) The lower surface of the light-transmitting member is rectangular. A method for manufacturing a light-emitting device according to any one of appendices 1 to 7, wherein, prior to the spreading step, an uncured third bonding member with a higher viscosity than the uncured second bonding member is placed at the four corners of the lower surface of the light-transmitting member. (Note 9) The method for manufacturing a light-emitting device according to any one of appendices 1 to 8, wherein in the spreading step, the first bonding member is arranged so as to be in contact with the outer edge of the upper surface of the light-emitting element at the four corners of the upper surface of the light-emitting element when viewed from above. (Note 10) A method for manufacturing a light-emitting device according to any one of the appendices 1 to 9, wherein in the spreading step, the corner of the lower surface of the light-transmitting member comes into contact with the second joining member. (Note 11) The method for manufacturing a light-emitting device according to any one of appendices 1 to 10, wherein in the spreading step, the second bonding member is placed in the entire region sandwiched between the upper surface of the light-emitting element and the lower surface of the light-transmitting member. (Note 12) Light-emitting element and Translucent material, The device comprises a bonding member positioned between the upper surface of the light-emitting element and the lower surface of the light-transmitting member, and in contact with the entire lower surface of the light-transmitting member. The joining member includes light scattering particles, A light-emitting device in which the bonding member located in a position that does not overlap with the light-emitting element when viewed from above includes a region in which the density of light-scattering particles is higher than that of the bonding member located in a position that overlaps with the light-emitting element when viewed from above. (Note 13) The light-emitting device according to Appendix 12, wherein the region in the bonding member with a high concentration of light-scattering particles includes a portion that is arranged to be in contact with the outer edge of the upper surface of the light-emitting element when viewed from above. [Explanation of Symbols]

[0104] 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 40h area 50 Translucent material 50a top 50b Bottom side 50c side 60 Covering member 61 First covering member 62 Second covering member 401 First Joining Member 402 Second Joining Member 403 Third Joining Member

Claims

1. The process of preparing the light-emitting element, A step of preparing a light-transmitting member having a lower surface area larger than the upper surface of the light-emitting element, The steps include: placing an uncured first bonding member on at least a portion of the outer peripheral region of the upper surface of the light-emitting element; A step of placing an uncured second bonding member, which has a lower viscosity than the uncured first bonding member, on the upper surface of the light-emitting element exposed from the first bonding member, The steps include pressing the first joining member and the second joining member against the lower surface of the light-transmitting member and spreading the first joining member and / or the second joining member over the outer peripheral region of the lower surface of the light-transmitting member, A method for manufacturing a light-emitting device, comprising the steps of curing the first joining member and the second joining member.

2. The upper surface of the light-emitting element is rectangular. The method for manufacturing a light-emitting device according to claim 1, wherein in the step of arranging the first bonding member, uncured first bonding members are arranged at the four corners of the upper surface of the light-emitting element so as to be spaced apart from each other.

3. The method for manufacturing a light-emitting device according to claim 2, wherein in the step of arranging the second bonding member, an uncured second bonding member is placed in the central region located inside the outer peripheral region of the upper surface of the light-emitting element.

4. The method for manufacturing a light-emitting device according to claim 2, wherein in the step of arranging the second bonding member, the uncured second bonding member is arranged in the outer peripheral region of the upper surface of the light-emitting element and in the central region surrounded by the outer peripheral region of the upper surface of the light-emitting element.

5. A method for manufacturing a light-emitting device according to any one of claims 1 to 4, wherein the viscosity of the uncured first bonding member is 30 Pa·s or more and 120 Pa·s or less.

6. The method for manufacturing a light-emitting device according to any one of claims 1 to 4, wherein the viscosity of the uncured second bonding member is 0.1 Pa·s or more and 15 Pa·s or less.

7. A method for manufacturing a light-emitting device according to any one of claims 1 to 4, wherein the volume of the uncured second bonding member placed on the light-emitting element in the step of placing the second bonding member is greater than the volume of the uncured first bonding member placed on the light-emitting element in the step of placing the first bonding member.

8. The lower surface of the light-transmitting member is rectangular. A method for manufacturing a light-emitting device according to any one of claims 1 to 4, wherein, prior to the spreading step, an uncured third bonding member having a higher viscosity than the uncured second bonding member is placed at the four corners of the lower surface of the light-transmitting member.

9. The method for manufacturing a light-emitting device according to any one of claims 1 to 4, wherein in the spreading step, the first bonding member is arranged so as to be in contact with the outer edge of the upper surface of the light-emitting element at the four corners of the upper surface of the light-emitting element when viewed from above.

10. The method for manufacturing a light-emitting device according to any one of claims 1 to 4, wherein in the spreading step, the corner of the lower surface of the light-transmitting member comes into contact with the second joining member.

11. The method for manufacturing a light-emitting device according to any one of claims 1 to 4, wherein in the spreading step, the second bonding member is placed in the entire region sandwiched between the upper surface of the light-emitting element and the lower surface of the light-transmitting member.

12. Light-emitting element and Translucent material, The device has a bonding member that is positioned between the upper surface of the light-emitting element and the lower surface of the light-transmitting member and is in contact with the entire lower surface of the light-transmitting member. The joining member includes light scattering particles, A light-emitting device in which the bonding member located in a position that does not overlap with the light-emitting element when viewed from above includes a region in which the density of light-scattering particles is higher than that of the bonding member located in a position that overlaps with the light-emitting element when viewed from above.

13. The light-emitting device according to claim 12, wherein the region in the bonding member with a high concentration of light-scattering particles includes a portion that is arranged to be in contact with the outer edge of the upper surface of the light-emitting element when viewed from above.

Images