CN110707202A

CN110707202A - Light emitting device and method for manufacturing the same

Info

Publication number: CN110707202A
Application number: CN201910613626.2A
Authority: CN
Inventors: 相原正人; 小关健司; 小岛淳资; 中井千波; 田村和也
Original assignee: Nichia Chemical Industries Ltd
Current assignee: Nichia Corp; Nichia Chemical Industries Ltd
Priority date: 2018-07-09
Filing date: 2019-07-09
Publication date: 2020-01-17
Also published as: KR20200006017A; TW202013769A; JP2020013986A; JP7348478B2

Abstract

The invention provides a light emitting device capable of improving light output efficiency. The light emitting device includes: a substrate including a base material having an upper surface and a first wiring disposed on the upper surface; a first light emitting element having a first light output surface, a first electrode formation surface, and a first side surface, the first electrode formation surface and the first wiring being placed on the first wiring so as to face each other; a first reflecting member that exposes the first light output surface, covers the upper surface of the base material, and contains reflective particles; a first covering member that exposes the first light output surface, covers the first reflecting member and at least a part of the first side surface, and has a lower concentration of reflecting particles than the first reflecting member; a second covering member covering at least a part of the first side surface; and a second reflecting member that surrounds the second covering member in a plan view and is in contact with the second covering member and the first reflecting member, wherein the second reflecting member has a narrow portion and a wide portion that are in contact with the first reflecting member in a cross-sectional view.

Description

Light emitting device and method for manufacturing the same

Technical Field

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

Background

In recent years, light-emitting devices including light-emitting elements such as light-emitting diodes have been used for various applications, and light-emitting devices having higher light output efficiency have been demanded. For example, patent document 1 describes a light-emitting device in which light output efficiency is improved by providing a filler-containing resin that covers a side surface of a silicon substrate of a semiconductor light-emitting element and exposes an upper surface of the semiconductor light-emitting element.

Documents of the prior art

Patent document

Patent document 1: japanese unexamined patent publication No. 2014-241341

Disclosure of Invention

An object of the present invention is to provide a light-emitting device including a filler-containing resin (reflective particle-containing member) and capable of further improving light output efficiency, and a method for manufacturing the light-emitting device.

A light-emitting device according to an aspect of the present invention includes: a substrate including a base material having an upper surface and a first wiring disposed on the upper surface; a first light emitting element having: a first light output surface, a first electrode forming surface located on the opposite side of the first light output surface, a first side surface located between the first light output surface and the first electrode forming surface, and a pair of first electrodes provided on the first electrode forming surface, the first electrode forming surface and the first wirings being placed on the first wirings so as to face each other; a first reflecting member that exposes the first light output surface, covers the upper surface of the substrate, and contains reflective particles; a first covering member that exposes the first light output surface, covers the first reflecting member and at least a part of the first side surface, and has a lower concentration of the reflective particles than the first reflecting member; a second covering member covering at least a part of the first side surface; and a second reflecting member that surrounds the second covering member in a plan view and is in contact with the second covering member and the first reflecting member, wherein the second reflecting member has a narrow portion in contact with the first reflecting member in a cross-sectional view and a wide portion arranged above the narrow portion.

A method for manufacturing a light-emitting device according to an aspect of the present invention includes: a step of preparing a substrate having a base material having an upper surface and a first wiring disposed on the upper surface; a step of preparing a first light-emitting element having: a first light output surface, a first electrode forming surface located on the opposite side of the first light output surface, a first side surface located between the first light output surface and the first electrode forming surface, and a pair of first electrodes provided on the first electrode forming surface; a step of mounting a first light-emitting element on the first wiring so that the first electrode formation surface faces the first wiring; disposing a reflective particle-containing member on the upper surface of the base material such that at least a part of the upper surface of the base material overlapping the first light-emitting element is exposed in a plan view; and spreading the reflective particle-containing member on the upper surface of the base material overlapping the first light-emitting element by a centrifugal force.

According to the light-emitting device of the embodiment of the present invention, a light-emitting device with improved light output efficiency can be provided.

Drawings

Fig. 1A is a schematic perspective view of a light-emitting device according to embodiment 1.

Fig. 1B is a schematic perspective view of the light-emitting device according to embodiment 1.

Fig. 2A is a schematic plan view of the light-emitting device according to embodiment 1.

FIG. 2B is a schematic sectional view taken along line IIB-IIB of FIG. 2A.

FIG. 2C is a schematic cross-sectional view taken along line IIC-IIC of FIG. 2A.

Fig. 3 is a schematic cross-sectional view of a modification of the light-emitting device of embodiment 1.

Fig. 4 is a schematic cross-sectional view of a modification of the light-emitting device of embodiment 1.

Fig. 5 is a schematic cross-sectional view of a modification of the light-emitting device of embodiment 1.

Fig. 6 is a schematic plan view of the substrate according to embodiment 1.

Fig. 7 is a schematic rear view of the light-emitting device according to embodiment 1.

Fig. 8 is a schematic front view of a light-emitting device according to embodiment 1.

Fig. 9 is a schematic side view of a light-emitting device according to embodiment 1.

Fig. 10 is a schematic cross-sectional view of a light-emitting device according to embodiment 2.

Fig. 11 is a schematic cross-sectional view for explaining a method of manufacturing a light-emitting device according to embodiment 1.

Fig. 12 is a schematic cross-sectional view for explaining a method of manufacturing a light-emitting device according to embodiment 1.

Fig. 13 is a schematic diagram for explaining a method of manufacturing the light-emitting device according to embodiment 1.

Fig. 14 is a schematic cross-sectional view for explaining a method of manufacturing the light-emitting device of embodiment 1.

Fig. 15 is a schematic cross-sectional view for explaining a method of manufacturing the light-emitting device of embodiment 1.

Fig. 16 is a schematic cross-sectional view for explaining a method of manufacturing the light-emitting device of embodiment 1.

Fig. 17 is a schematic cross-sectional view for explaining a method of manufacturing the light-emitting device of embodiment 1.

Fig. 18 is a schematic cross-sectional view for explaining a method of manufacturing a light-emitting device according to embodiment 1.

Description of the symbols

1000A, 1000B, 1000C, 2000 light emitting device

10 base plate

11 base material

118 recess

12 first wiring

13 second wiring

14 third wiring

15 via hole

151 fourth wiring

152 filling member

16 concave part

18 insulating film

20A first light emitting element

20B second light emitting element

20C third light emitting element

30 parts containing reflective particles

31 first reflecting member

32 first cover part

33 second coating member

34 adhesive layer

40 second reflecting member

50 light-transmitting member

60 conductive adhesive member

70 gap

80 rotating shaft

Detailed Description

Embodiments of the present invention will be described below with reference to the accompanying drawings as appropriate. However, the light-emitting device described below is a device for embodying the technical idea of the present invention, and the present invention is not limited to the following device unless otherwise specified. The contents described in one embodiment can be applied to other embodiments and modifications. In addition, the sizes, positional relationships, and the like of the components shown in the drawings are often exaggerated for clarity of description. Further, the same names and symbols denote the same or similar members, and detailed description thereof will be omitted as appropriate.

< embodiment 1 >

Next, a light-emitting device 1000 according to an embodiment of the present invention will be described with reference to fig. 1A to 9. The light-emitting device 1000 includes a substrate 10, at least one first light-emitting element 20A, a first reflecting member 31, a first covering member 32, a second covering member 33, and a second reflecting member 40. The substrate 10 includes: a substrate 11 having an upper surface 111, and a first wiring 12 disposed on the upper surface 111 of the substrate 11. The first light-emitting element 20A has: the first light output surface 201A, a first electrode formation surface 203A located on the opposite side of the first light output surface, a first side surface 202A located between the first light output surface and the first electrode formation surface, and a pair of

first electrodes

21A and 22A provided on the first electrode formation surface 203A. The first light-emitting element 20A is mounted on the first wiring 12 such that the first electrode-formed surface 203A faces the first wiring 12. The first light emitting element 20A is electrically connected to the first wiring 12. The first reflecting member 31 exposes the first light output surface 201A and covers the upper surface 111 of the substrate 11. In addition, the first reflecting member 31 contains reflecting particles. The first cladding member 32 exposes the first light output surface 201A, cladding the first reflecting member 31 and at least a portion of the first side surface 202A. In addition, the first coating member 32 has a lower concentration of reflective particles than the first reflection member 31. The second covering member 33 covers at least a part of the first side 202A. The second reflecting member 40 surrounds the second covering member 33 in a plan view. The second reflecting member 40 is in contact with the second covering member 33 and the first reflecting member 31. The second reflecting member 40 has a narrow portion 42 in contact with the first reflecting portion 31 and a wide portion 41 arranged above the narrow portion 42 in cross section. The second light-emitting element 20B, the third light-emitting element 20C, and the first light-emitting element 20A, which will be described later, may be collectively referred to as a light-emitting element.

The first cladding member 32 has a higher light transmittance than the first reflecting member 31 because the concentration of the reflective particles is lower than that of the first reflecting member 31. Therefore, by providing the first covering member 32 covering the first side surface 202A, light from the first light-emitting element 20A can be output from the first covering member 32 having high light transmittance. This can improve the light output efficiency of the light-emitting device.

By coating the upper surface of the base material 11 with the first reflecting member 31 containing reflective particles and having a high reflectance, it is possible to suppress absorption of light from the first light-emitting element 20A into the substrate 10. This can improve the light output efficiency of the light-emitting device.

As the order of forming the first reflecting member 31 and the first coating member 32, the first reflecting member may be formed and then the first coating member coating the first reflecting member may be formed, or the first reflecting member and the first coating member may be formed in the same step. For example, after the first reflecting member is formed, the first coating member before curing is disposed on the upper surface of the base material by casting or the like, and the first coating member is cured. Thus, the first covering member covering the first reflecting member can be formed. In the case where the first reflective member and the first coating member are formed in the same step, for example, a member containing reflective particles before curing, which contains reflective particles, is disposed on a substrate, and the reflective particles of the member containing reflective particles are precipitated by centrifugal force or the like. When the reflective particles of the reflective particle-containing member are precipitated, a reflective portion in which the reflective particles are unevenly distributed and a light-transmitting portion which is located above the reflective portion and in which the reflective particles are not unevenly distributed are formed in the reflective particle-containing member. In addition, a reflection portion in which the reflective particles are uniformly distributed in the reflective particle-containing member is referred to as a first reflection member 31, and a light transmission portion which is located above the reflection portion and in which the reflective particles are not uniformly distributed is referred to as a first covering member 32. In the case where the first coating member is formed by precipitating the reflective particles of the reflective particle-containing member, the first coating member 32 may contain reflective particles that are not precipitated due to particle size or the like. The first reflecting member 31 can be easily made thin by precipitating the reflecting particles of the reflecting particle-containing member. This makes it easy to output light from the first light-emitting element 20A from the first covering member 32, and therefore, the light output efficiency of the light-emitting device can be improved. In the case of precipitating the reflective particles of the reflective particle-containing member, the first reflective member 31 is a portion in which the content of the reflective particles in the reflective particle-containing member is 10 wt% or more, and the first coating member 32 is a portion in which the content of the reflective particles in the reflective particle-containing member is less than 10 wt%. Further, "wt%" is a weight percentage indicating a ratio of the weight of the reflective particles to the total weight of the reflective particle-containing member.

The base material of the first covering member 32 may be light-transmissive, and a known member such as a silicone resin may be used. The term "light transmittance" means a light transmittance at the emission peak wavelength of the first light-emitting element of preferably 60% or more, more preferably 70% or more, and still more preferably 80% or more. When the first reflecting member 31 and the first covering member 32 are formed in the same step, a member containing reflecting particles in a known transparent base material can be used as the reflecting particle-containing member to be used. As the first reflecting member 31, a member in which a base material contains reflecting particles can be used. As reflective particles. A known material such as titanium oxide can be used. The first reflecting member 31 may have reflectivity for reflecting light from the first light emitting element, and may be a member containing reflecting particles in a base material, for example. The reflectance of the first reflecting member at the emission peak wavelength of the first light-emitting element is preferably 60% or more, more preferably 70% or more, and still more preferably 80% or more.

The first covering member 32 may or may not be in contact with the second reflecting member 40. When the first cladding member 32 is in contact with the second reflecting member 40, the area of the first cladding member 32 having high light transmittance can be increased in a plan view, and therefore, light of the first light-emitting element 20A is easily diffused in the X direction and the Y direction by the first cladding member 32, and therefore, luminance unevenness of the light-emitting device can be suppressed.

As in the light-emitting device 1000 shown in fig. 2B and 2C, in the first cladding member 32, the thickness of the first cladding member 32 in a portion in contact with the first light-emitting element 20A may be larger than the thickness of the first cladding member 32 in a portion away from the first light-emitting element 20A. For example, in the case where the first and

second covering members

32 and 40 are in contact, the thickness of the first covering member 32 of a portion in contact with the first light emitting element 20A may be thicker than the thickness of the first covering member 32 of a portion in contact with the second reflecting member 40 with respect to the first covering member 32. As in the light-emitting device 1000A shown in fig. 3, the upper surface of the first covering member 32 may be flat. In the case where the thickness of the first covering member 32 in the portion in contact with the first light-emitting element 20A is thicker than the thickness of the first covering member 32 in the portion away from the first light-emitting element 20A, the joint area between the first side surface 202A and the first covering member 32 is easily increased. This makes it easy to output light from the first light-emitting element 20A from the first covering member 32, and therefore, the light output efficiency of the light-emitting device is improved. In the case where the upper surface of the first covering member is flat, it is easy to suppress the shape deviation of the first covering member 32 of each light emitting device. This can improve the yield of the light-emitting device. The shape of the first cladding member 32 may be altered, for example, by adjusting the viscosity of the first cladding member and/or the reflective particle-containing member. In the present specification, the term "flat" allows a fluctuation of about ± 5 μm.

The light-emitting device may include one light-emitting element, and as shown in fig. 2B, the light-emitting device may include two light-emitting elements, i.e., a first light-emitting element 20A and a second light-emitting element 20B. In the case where the light-emitting device includes the first light-emitting element and the second light-emitting element, the first covering member 32 is preferably in contact with the first light-emitting element 20A and the second light-emitting element 20B. This allows light from the first light-emitting element and light from the second light-emitting element to be guided to the first covering member. For example, when the emission peak wavelengths of the first light-emitting element and the second light-emitting element are the same, the light from the first light-emitting element and the light from the second light-emitting element are guided to the first covering member, whereby a decrease in luminance between the first light-emitting element and the second light-emitting element can be suppressed. This can suppress luminance unevenness of the light-emitting device. In addition, when the emission peak wavelengths of the first light-emitting element and the second light-emitting element are different from each other, the color mixing property of the light-emitting device can be improved by guiding the light from the first light-emitting element and the light from the second light-emitting element to the first covering member. In the present specification, the phrase "the emission peak wavelengths are the same" allows fluctuations of about ± 10 nm.

The first reflecting member 31 may or may not be in contact with the first light emitting element 20A. As shown in fig. 2B, when the first reflecting member 31 and the first light emitting element 20A are in contact, the first reflecting member 31 preferably directly covers the pair of

first electrodes

21A and 22A. This can suppress absorption of light from the first light-emitting element 20A by the

first electrodes

21A and 22A. In addition, when the first reflecting member 31 and the first light emitting element 20A are in contact, the first reflecting member 31 preferably covers the side surface of the first semiconductor layer 23A of the first light emitting element 20A. This can increase the thickness of the first reflecting member 31 in the Z direction, and therefore the first reflecting member 31 can easily cover the pair of

first electrodes

21A and 22A.

The first reflecting member 31 may cover the first electrode forming surface 203A. The first reflecting member 31 may cover the first electrode formation surface 203A directly or may cover the first electrode formation surface 203A via the first covering member 32. Thus, since the light from the first light emitting element 20A is reflected by the first reflecting member 31, the light from the first light emitting element 20A can be suppressed from being absorbed by the substrate 10. This improves the light output efficiency of the light-emitting device.

As shown in fig. 2B, when the light-emitting device 1000 includes the first light-emitting element 20A and the second light-emitting element 20B, the first reflecting member 31 preferably covers the first electrode-formed surface 203A and the second electrode-formed surface 203B. Accordingly, the light from the first light emitting element 20A and the light from the second light emitting element 20B are reflected by the first reflecting member 31, and therefore, the light output efficiency of the light emitting device 1000 can be improved.

When the first reflecting member 31 covers the first side surface 202A of the first light-emitting element 20A, the length H1 of the contact between the first reflecting member 31 and the first side surface 202A in the Z direction is preferably 0.5 times or less, and more preferably 0.3 times or less, the length H2 of the first side surface 202A. This makes it difficult for light traveling in the X direction and/or the Y direction from the first light-emitting element 20A to be blocked, and therefore, unevenness in luminance of the light-emitting device can be suppressed.

The maximum thickness of the first reflecting member 31 in the Z direction is preferably 10 μm to 200 μm, for example. If the maximum thickness of the first reflecting member 31 is 10 μm or more, the first reflecting member 31 will be easily formed. In addition, if the maximum thickness of the first reflecting member 31 is 200 μm or less, the first reflecting member 31 which does not face a part of the first side surface of the first light emitting element 20A can be easily formed. This makes it difficult for light traveling in the X direction and/or the Y direction from the first light-emitting element 20A to be blocked, and therefore, unevenness in luminance of the light-emitting device can be suppressed.

When the light-emitting device includes a plurality of light-emitting elements, the light-emitting peak wavelengths of the plurality of light-emitting elements may be the same or different. By making the emission peak wavelengths of the plurality of light-emitting elements different, the color reproducibility of the light-emitting device can be improved. For example, the emission peak wavelength of the first light-emitting element 20A may be in the range of 430nm to 490nm (wavelength range of blue region), and the emission peak wavelength of the second light-emitting element 20B may be in the range of 490nm to 570nm (wavelength range of green region). The first light-emitting element 20A will be described as an example of the structure of the light-emitting element.

The first light emitting element 20A has a first light output surface 201A, a first electrode forming surface 203A located on the opposite side of the first light output surface, and a first side surface 202A located between the first light output surface 201A and the first electrode forming surface 203A. The first side 202A may be perpendicular with respect to the first light output face 201A, or may be inclined inwardly or outwardly. A pair of

first electrodes

21A and 22A is provided on the first electrode formation surface 203A.

The first light-emitting element 20A includes a first element substrate 24A and a first semiconductor layer 23A formed so as to be in contact with the first element substrate 24A. The pair of

first electrodes

21A and 22A is electrically connected to the first semiconductor layer 23A. In the present embodiment, the description has been given taking as an example a configuration in which the first light-emitting element 20A includes the first element substrate 24A, but the first element substrate 24A may be eliminated.

The shape of the first light-emitting element 20A in a plan view may be a triangle, a quadrangle, a hexagon, or another shape. As shown in fig. 2A, when the light-emitting device 1000 includes the first light-emitting element 20A and the second light-emitting element 20B and the first light-emitting element 20A and the second light-emitting element 20B have rectangular shapes in plan view, one short side 2011A of the first light output surface 201A of the first light-emitting element and one short side 2011B of the second light output surface 201B of the second light-emitting element are preferably arranged to face each other. This can reduce the thickness of the light-emitting device 1000 in the Y direction.

The first light output surface 201A and the second light output surface 201B may be substantially the same height in the Z direction, or may be different heights. In addition, the first light output surface 201A and the second light output surface 201B may have the same area or different areas in a plan view. In particular, when the light-emitting device includes the wavelength conversion member, the larger the light output surface of the light-emitting element having the emission peak wavelength at which the wavelength conversion member is easily excited, the better. The wavelength conversion member absorbs at least a part of the primary light emitted from the light emitting element and emits secondary light having a wavelength different from that of the primary light. For example, a light-emitting device is provided with a phosphor (e.g., K) of manganese-activated potassium fluorosilicate as a wavelength conversion member emitting red light₂SiF₂Mn), and the emission peak wavelength of the first light-emitting element is in the range of 430nm to 490nm (wavelength range of blue region), and the emission peak wavelength of the second light-emitting element is in the range of 490nm to 570nm (wavelength range of green region), the first light output surface 201A of the first light-emitting element 20A is preferably larger than the second light output surface 201B of the second light-emitting element 20B. For example, the first light output face 201A of the first light emitting element 20A is preferably 1.2 times or more and 2 times or less the second light output face 201B of the second light emitting element 20B. A phosphor (for example, K) in which potassium fluosilicate is activated by manganese as compared with light having a wavelength of 490 to 570nm₂SiF₆: mn) is more easily excited by light of 430nm to 490 nm. Since the first light output surface 201A of the first light emitting element is larger than the second light output surface 201B of the second light emitting element, the proportion of light from the first light emitting element 20A can be increased, and therefore, even if part of the light from the first light emitting element is converted by the manganese-activated fluoride-based phosphor, the proportion of light from the first light emitting element emitted from the light emitting device can be suppressed from decreasing. This can improve the color reproducibility of the light-emitting device 1000.

The second covering member 33 has light-transmitting properties and covers at least a part of the first side surface 202A. Since the second covering member 33 covers the first side surface 202A, light from the first light-emitting element 20A can be output from the second covering member 33, and thus the light output efficiency of the light-emitting device is improved. The second covering member 33 may cover the first side surface 202A directly or may cover the first side surface 202A via the first covering member 32. The second covering member 33 may include both a portion directly covering the first side surface 202A and a portion covering the first side surface 202A via the first covering member 32. When the refractive index difference between the base material of the first covering member 32 and the first element substrate 24A is smaller than the refractive index difference between the base material of the second covering member 33 and the first element substrate 24A, the second covering member 33 preferably covers the first side surface 202A including the side surface of the first element substrate 24A via the first covering member 32. Thus, since the bonding area between the first covering member 32 and the first element substrate 24A is easily increased, light from the first light-emitting element is easily output from the first covering member 32. When the refractive index difference between the base material of the first cladding member 32 and the first semiconductor layer 23A is smaller than the refractive index difference between the base material of the second cladding member 33 and the first element substrate 24A, the second cladding member 33 preferably includes a portion in which the first side surface 202A including the side surface of the first semiconductor layer 23A is clad via the first cladding member 32. This makes it easy to output light from the first light-emitting element from the first covering member 32.

The second coating member 33 may coat the first light output surface 201A as in the light emitting device 1000B shown in fig. 4, or the second coating member 33 may expose the first light output surface 201A as in the light emitting device 1000 shown in fig. 2B. In the case where the second covering member 33 covers the first light output surface 201A, the first light emitting element 20A can be protected from an external force from the first light output surface 201A. When the first light output surface 201A is exposed from the second covering member 33, the thickness of the light emitting device in the Z direction can be reduced, and thus the light emitting device can be downsized.

When the light-emitting device includes the second light-emitting element 20B, the second coating member 33 preferably coats the first side surface 202A and the second side surface 202B. This facilitates guiding the light from the first light-emitting element 20A and the light from the second light-emitting element 20B to the second coating member 33. For example, when the emission peak wavelengths of the first light-emitting element and the second light-emitting element are the same, luminance unevenness between the first light-emitting element and the second light-emitting element can be suppressed by guiding the light from the first light-emitting element and the light from the second light-emitting element to the second covering member. In addition, when the emission peak wavelengths of the first light-emitting element and the second light-emitting element are different from each other, the color mixing property of the light-emitting device can be improved by guiding the light from the first light-emitting element and the light from the second light-emitting element to the second covering member. The second covering member may be in contact with the first side surface and/or the second side surface, or may cover the first side surface and/or the second side surface via the first covering member.

The second coating member 33 may contain a wavelength conversion member. Thereby, color adjustment of the light emitting device becomes easy. The wavelength conversion member may be uniformly dispersed in the second coating member 33, or the wavelength conversion member may be distributed at a position closer to the first coating member than the upper surface of the second coating member. Examples of the wavelength conversion member included in the second coating member include a green light-emitting wavelength conversion member having an emission peak wavelength of 490 to 570nm inclusive, a red light-emitting wavelength conversion member having an emission peak wavelength of 610 to 750nm inclusive, and the like. The wavelength conversion member contained in the second coating member may be one type or may include a plurality of types. For example, a wavelength conversion member that emits green light and a wavelength conversion member that emits red light may be included in the light guide member. Examples of the green-emitting wavelength conversion member include a β sialon-based phosphor (e.g., Si)_6－zAl_zO_zN_8－zEu (z is more than 0 and less than 4.2). Examples of the red-light-emitting wavelength conversion member include a phosphor (e.g., K) of manganese-activated potassium fluosilicate₂SiF₆︰Mn)。

The second reflecting member 40 surrounds the second covering member 33 in a plan view, and is in contact with the second covering member 33 and the first reflecting member 31. In cross section, the second reflecting member 40 has a narrow portion 42 in contact with the first reflecting member 31 and a wide portion 41 arranged above the narrow portion 42. Second reflective member 40 has an inner side 401 and an outer side 402. The widths of the narrow portion 42 and the wide portion 41 are the shortest distances from the inner surface 401 to the outer surface 402.

The second reflecting member 40 has a ring shape in a plan view. Further, since the second reflecting member 40 surrounds the second covering member 33, the light traveling in the X direction and/or the Y direction from the first light emitting element 20A can be reflected by the second reflecting member 40, and the light traveling in the Z direction can be increased.

As the second reflecting member 40, for example, a known member such as a resin material containing reflecting particles in a matrix can be used. As a method of forming the second reflecting member 40, for example, a second reflecting member can be formed by forming a notch in the first reflecting member 31 and the second covering member 33, filling the notch with the second reflecting member before curing, and curing the second reflecting member before curing. For example, by using a blade having a narrow width portion and a wide width portion, the notch formed by the blade can also have a narrow width portion and a wide width portion. The tip of the blade is a narrow portion. By making the tip of the blade a narrow portion, it is easier to form the notch in the first reflecting member 31 and the second covering member 33 than in the case of using a blade having a constant width.

The narrow-width portion 42 of the second reflecting member 40 contacts the first reflecting member 31. This can prevent light from the first light-emitting element 20A from passing through the narrow portion 42 of the second reflecting member 40, which is thin, from the narrow portion of the second reflecting member 40. Therefore, the light output efficiency of the light emitting device can be improved.

The width of the wide portion 41 of the second reflecting member 40 is preferably 10 μm to 50 μm in a plan view. By setting the width of the first reflecting member to 50 μm or less, the light emitting device can be miniaturized. Further, by setting the width of the first reflecting member to 10 μm or more, it is possible to suppress light from the first light emitting element from passing through the wide portion 41 of the second reflecting member 40.

The substrate 10 has a base material 11 and a first wiring 12. The substrate 11 has: upper surface 111, lower surface 112 located on the opposite side of the upper surface, back surface 113 contacting upper surface 111 and perpendicular to upper surface 111, and front surface 114 located on the opposite side of back surface 113. In addition, the substrate 11 has a side surface 115 between the upper surface 111 and the lower surface 112.

The substrate 11 is particularly preferably formed of a material having physical properties close to the linear expansion coefficient of the first light-emitting element 20A, and examples thereof include insulating members such as resin, fiber-reinforced resin, ceramics, and glass. Examples of the resin or the fiber-reinforced resin include epoxy resin, glass epoxy resin, Bismaleimide Triazine (BT), polyimide, and the like, and examples of the ceramic include alumina, aluminum nitride, zirconia, zirconium nitride, titanium oxide, titanium nitride, and a mixture thereof.

From the viewpoint of strength, the lower limit of the thickness of the substrate 11 is preferably 0.05mm or more, and more preferably 0.2mm or more. In addition, the upper limit value of the thickness of the base material 11 is preferably 0.5mm or less, and more preferably 0.4mm or less, from the viewpoint of the thickness (depth) of the light-emitting device in the Z direction.

As shown in fig. 2B, the substrate 10 may include a second wiring 13 disposed on the lower surface 112. When the substrate 10 includes the first wiring 12 and the second wiring 13, the substrate 10 may include a via 15 connecting the first wiring 12 and the second wiring 13. The vias 15 are preferably circular in plan view. This enables easy formation by a drill or the like. When the via hole 15 is circular in a plan view, the diameter of the via hole is preferably 100 μm or more and 150 μm or less. The heat dissipation of the light-emitting device is improved by making the diameter of the via hole 100 μm or more, and the strength drop of the base material can be reduced by making the diameter of the via hole 150 μm or less. In the present specification, the term "circular" includes not only a perfect circle but also a shape that approximates a perfect circle (for example, an ellipse or a quadrangle may have its four corners processed into a large circular arc).

The via hole 15 may be formed by filling a conductive material in the through hole of the substrate 11, and as shown in fig. 2B, may include a fourth wiring 151 covering the surface of the through hole of the substrate 11 and a filling member 152 filled in a region surrounded by the fourth wiring 151. The filler member 152 may be conductive or insulating. As the filling member 152, a resin material is preferably used. The resin material before curing is generally higher in fluidity than the metal material before curing, and therefore is easily filled in the fourth wiring 151. Therefore, by using a resin material as the filling member, the manufacture of the substrate becomes easy. Examples of the resin material which can be easily filled include epoxy resins. In the case of using a resin material as the filler, it is preferable to include an additive in order to reduce the linear expansion coefficient. This reduces the difference in linear expansion coefficient with the fourth wiring, and therefore, formation of a gap between the fourth wiring and the filling member due to heat from the light-emitting element can be suppressed. Examples of the additive member include silicon oxide. In addition, when a metal material is used as the filler member 152, heat dissipation can be improved. When the via hole 15 is formed by filling a conductive material in the through hole of the base material, a metal material having high thermal conductivity, such as Ag or Cu, is preferably used.

As shown in fig. 2B, the first wiring 12 preferably includes a convex portion 121 at a position corresponding to the pair of

first electrodes

21A and 22A of the first light-emitting element 20A. In other words, the first wiring 12 preferably includes the convex portion 121 at a position overlapping the

first electrodes

21A and 22A in a plan view. By providing the first wiring 12 with the convex portion 121, alignment between the first light-emitting element and the substrate can be easily performed by the self-alignment effect when the first wiring 12 and the

first electrodes

21A and 22A are connected via the conductive adhesive member 60. The thickness of the convex portion 121 in the Z direction is preferably 10 μm to 30 μm. The width of the convex portion 121 in the X direction and/or the Y direction may be appropriately changed according to the size of the electrode of the light emitting element facing each other.

The conductive adhesive member 60 is a member for electrically connecting the pair of

first electrodes

21A and 22A provided in the first light-emitting element 20A and the first wiring 12. As the material of the conductive adhesive member 60, known materials such as bumps of gold, silver, copper, or the like, metal paste containing metal powder of silver, gold, copper, platinum, aluminum, palladium, or the like and a resin binder, solder of tin-bismuth type, tin-copper type, tin-silver type, gold-tin type, or the like, solder of low melting point metal, or the like can be used.

When the light-emitting device includes the second light-emitting element 20B, the first wire 12 preferably includes the convex portion 121 at a position corresponding to the pair of

electrodes

21B and 22B of the second light-emitting element. This makes it possible to easily align the light emitting element and the substrate by the self-alignment effect.

The substrate 11 may or may not have the recess 16 formed with ロ on the lower surface 112 of the substrate and the back surface 113 of the substrate. When the recess 16 is provided, the bonding strength between the light-emitting device 1000A and the mounting substrate can be improved. The light-emitting device 1000 can be of either a top-emission type (top-emission type) in which the lower surface 112 of the base material 11 is mounted so as to face the mounting board or a side-emission type (side-emission type) in which the rear surface 113 of the base material 11 is mounted so as to face the mounting board, and the bonding strength with the mounting board can be improved by increasing the volume of the bonding member. In particular, in the case of the side light emission type, the bonding strength between the light emitting device 1000 and the mounting substrate can be improved. The number of the recesses of the base material may be one or more. By having a plurality of concave portions, the bonding strength between the light-emitting device 1000 and the mounting substrate can be further improved.

The maximum values of the depths of the recesses 16 in the Z direction are preferably 0.4 to 0.9 times the thickness of the base material 11 in the Z direction, respectively. By making the depth of the recess deeper than 0.4 times the thickness of the base material, the volume of the joining member formed in the recess increases, and therefore the joining strength between the light-emitting device and the mounting substrate can be improved. By making the depth of the recess shallower than 0.9 times the thickness of the base material, a decrease in the strength of the base material can be suppressed.

As in the light-emitting device 1000 shown in fig. 2B, the upper surface 111 of the substrate 11 may have the recess 118, or as in the light-emitting device 1000C shown in fig. 5, the upper surface 111 of the substrate 11 may not have the recess 118. When the upper surface 111 of the substrate 11 has the recess 118, a part of the second reflecting member 40 is preferably disposed in the recess 118. This brings the base material 11 and the second reflecting member 40 into contact with each other, thereby improving the bonding strength between the base material and the second reflecting member. As shown in fig. 6, the concave portion 118 formed in the upper surface 111 of the substrate 11 is preferably formed so as to surround the outer periphery of the upper surface 111 of the substrate 11. This increases the area of contact between the base material 11 and the second reflecting member 40, and therefore improves the bonding strength between the base material and the second reflecting member.

As in the light-emitting device 1000 shown in fig. 7, 8, and 9, the outer edge of the base material is preferably flush with the outer surface 402 of the second reflecting member. This makes it possible to miniaturize the light-emitting device in the X direction and/or the Y direction.

The light emitting device 1000 may include an insulating film 18 covering a part of the second wiring 13. By providing the insulating film 18, insulation of the lower surface 112 and prevention of short circuit can be achieved. In addition, the second wiring 13 can be prevented from being peeled off from the base material 11.

The light-emitting device may also include a light-transmitting member 50 covering the first light output surface. The first light output surface 201A of the first light emitting element is covered with the light transmissive member 50, whereby the first light emitting element 20A can be protected from external stress. The light-transmissive member 50 may be coated in contact with the first light output surface, and may also coat the first light output surface via a light-transmissive adhesive layer 34, as shown in fig. 2B. When the light-emitting device includes the second light-emitting element 20B, the first light output surface 201A and the second light output surface 201B may be covered with a single light-transmissive member 50. Further, the light-emitting device may include a plurality of translucent members. For example, the light-emitting device may include a first light-transmitting member covering the first light output surface and a second light-transmitting member covering the second light output surface. When the first light output surface 201A and the second light output surface 201B are covered with a single light transmissive member 50, the light from the first light emitting element and the light from the second light emitting element are guided to the light transmissive member 50, whereby the luminance between the first light emitting element and the second light emitting element can be suppressed from being lowered. This can suppress luminance unevenness of the light-emitting device.

When the light-emitting device includes the light-transmissive member 50, the side surface of the light-transmissive member is preferably covered with the second reflective member. This makes it possible to produce a light-emitting device having high contrast between a light-emitting region and a non-light-emitting region and having good "visibility".

The light-transmitting member 50 may include a wavelength conversion member. Thereby, color adjustment of the light emitting device becomes easy. The wavelength conversion member included in the light-transmitting member preferably has an emission peak wavelength of 610nm to 750nm (wavelength range of red region). For example, since the emission peak wavelength of the first light-emitting element is in the wavelength range of the blue region and the emission peak wavelength of the second light-emitting element is in greenSince the wavelength of the wavelength conversion member is within the wavelength range of the red region, the color reproducibility of the light-emitting device is improved by setting the emission peak wavelength of the wavelength conversion member included in the light-transmitting member to be within the wavelength range of the red region. The wavelength conversion member contained in the light-transmitting member may be one type or may contain a plurality of types. For example, the light-transmitting member may include a wavelength conversion member that emits green light and a wavelength conversion member that emits red light. By providing the light-transmitting member with the wavelength conversion member that emits green light, color adjustment of the light-emitting device becomes easy. Examples of the green-emitting wavelength conversion member include a β sialon-based phosphor (e.g., Si)_6－zAl_zO_zN_8－zEu (z is more than 0 and less than 4.2). Examples of the red-light-emitting wavelength conversion member include a phosphor (e.g., K) of manganese-activated potassium fluosilicate₂SiF₂︰Mn)。

The wavelength conversion member may be uniformly dispersed in the light-transmissive member, or the wavelength conversion member may be biased to be distributed closer to the first light-emitting element than the upper surface of the light-transmissive member. By distributing the wavelength conversion member in the vicinity of the first light-emitting element with respect to the upper surface of the light-transmissive member, even if the wavelength conversion member that is not resistant to moisture is used, the base material of the light-transmissive member functions as a protective layer, and therefore deterioration of the wavelength conversion member can be suppressed. As in the light-emitting device 1000 shown in fig. 2B, the light-transmitting member 50 may include a layer 51 containing a wavelength conversion member and a layer 52 containing substantially no wavelength conversion member. The layer substantially not containing the wavelength conversion member is located above the layer containing the wavelength conversion member in the Z direction. Thus, since the layer substantially not containing the wavelength conversion member also functions as a protective layer, deterioration of the wavelength conversion member can be suppressed. Examples of the wavelength conversion member that is not resistant to moisture include a phosphor of potassium fluosilicate activated with manganese. The manganese-activated potassium fluorosilicate phosphor can emit light with a relatively narrow spectral width, and is a preferred member in view of color reproducibility. The phrase "substantially not containing a wavelength conversion member" means that the wavelength conversion member that is inevitably mixed is not excluded, and the content of the wavelength conversion member is preferably 0.05 wt% or less.

The wavelength conversion member-containing layer 51 of the light-transmitting member 50 may be a single layer or a plurality of layers. For example, as in the light-emitting device 1000A shown in fig. 3, the light-transmitting member 50 may include a first wavelength conversion layer 51A and a second wavelength conversion layer 51B covering the first wavelength conversion layer 51A. The second wavelength conversion layer 51B may directly cover the first wavelength conversion layer 51A, or may cover the first wavelength conversion layer 51A via another layer having optical transparency. The first wavelength conversion layer 51A is disposed closer to the first light output surface 201A of the first light emitting element 20A than the second wavelength conversion layer 51B. The emission peak wavelength of the wavelength conversion member included in the first wavelength conversion layer 51A is preferably shorter than the emission peak wavelength of the wavelength conversion member included in the second wavelength conversion layer 51B. Thus, the wavelength conversion member of the second wavelength conversion layer 51B can be excited by the light from the first wavelength conversion layer 51A excited by the first light emitting element. This can increase the light from the wavelength conversion member of the second wavelength conversion layer 51B.

The emission peak wavelength of the wavelength conversion member included in the first wavelength conversion layer 51A is preferably 500nm to 570nm, and the emission peak wavelength of the wavelength conversion member included in the second wavelength conversion layer 51B is preferably 610nm to 750 nm. This makes it possible to produce a light-emitting device with high color reproducibility. For example, the wavelength conversion member included in the first wavelength conversion layer 51A may be a β sialon-based phosphor, and the wavelength conversion member included in the second wavelength conversion layer 51B may be a manganese-activated potassium fluosilicate phosphor. When a phosphor of manganese-activated potassium fluosilicate is used as the wavelength conversion member contained in the second wavelength conversion layer 51B, it is particularly preferable that the light-transmitting member 50 includes the first wavelength conversion layer 51A and the second wavelength conversion layer 51B. While the manganese-activated potassium fluosilicate phosphor is likely to be saturated in luminance, the first wavelength conversion layer 51A is located between the second wavelength conversion layer 51B and the first light-emitting device 20A, whereby the manganese-activated potassium fluosilicate phosphor can be prevented from being excessively irradiated with light from the first light-emitting device. This can suppress deterioration of the phosphor of manganese-activated potassium fluosilicate.

(embodiment 2)

Next, a light-emitting device 2000 according to embodiment 2 of the present invention will be described with reference to fig. 10. The light-emitting device 2000 differs from the light-emitting device 1000 according to embodiment 1 in the number of light-emitting elements.

As shown in fig. 10, the light-emitting device 2000 includes a first light-emitting element 20A, a second light-emitting element 20B, and a third light-emitting element 20C. The emission peak wavelengths of the first light-emitting element 20A, the second light-emitting element 20B, and/or the third light-emitting element may be the same or different. The light-emitting device may further include 4 or more light-emitting elements.

When the first light-emitting element 20A, the second light-emitting element 20B, and the third light-emitting element 20C are arranged in this order in the X direction, the emission peak wavelength of the first light-emitting element 20A and the emission peak wavelength of the third light-emitting element 20C are preferably the same. This allows the third light-emitting element 20C to supplement the first light-emitting element 20A, for example, when the output of the first light-emitting element 20A is insufficient. Further, by locating the second light-emitting element 20B having an emission peak wavelength different from the emission peak wavelength of the first light-emitting element 20A and the emission peak wavelength of the third light-emitting element 20C between the first light-emitting element 20A and the third light-emitting element 20C, color unevenness can be reduced as compared with a case where the first light-emitting element 20A, the third light-emitting element 20C, and the second light-emitting element 20B are arranged in this order. For example, the light-emitting device may include: a first light-emitting element having an emission peak wavelength in a range of 430nm to 490nm (wavelength range of blue region), a second light-emitting element having an emission peak wavelength in a range of 490nm to 570nm (wavelength range of green region), and a third light-emitting element having an emission peak wavelength in a range of 430nm to 490nm (wavelength range of blue region).

Next, various components of the light-emitting device according to the embodiment of the present invention will be described.

(substrate 10)

The substrate 10 is a member on which the light emitting element is mounted. The substrate 10 includes a base material 11 and a first wiring 12.

(substrate 11)

The substrate 11 may be formed using an insulating member such as resin, fiber-reinforced resin, ceramic, or glass. Examples of the resin or fiber-reinforced resin include epoxy resin, glass epoxy resin, Bismaleimide Triazine (BT), polyimide, and the like. The substrate 11 may contain a white pigment such as titanium oxide. Examples of the ceramic include alumina, aluminum nitride, zirconia, zirconium nitride, titanium oxide, titanium nitride, and a mixture thereof. Among these substrates, a substrate having physical properties close to the linear expansion coefficient of the light-emitting element is particularly preferably used.

(first wiring 12)

The first wiring is disposed on the upper surface of the base material and electrically connected to the light emitting element. The first wiring may be formed of copper, iron, nickel, tungsten, chromium, aluminum, silver, gold, titanium, palladium, rhodium, or an alloy thereof. These metals or alloys may be used in a single layer or in multiple layers. In particular, copper or a copper alloy is preferable from the viewpoint of heat dissipation. In addition, a layer of silver, platinum, aluminum, rhodium, gold, or an alloy thereof may be provided on the surface layer of the first wiring in view of wettability and/or light reflectivity of the conductive adhesive member.

(second wiring 13, third wiring 14)

The second wiring is disposed on the lower surface of the substrate. The third wiring covers the inner wall of the recess and is electrically connected to the second wiring. The second wiring and the third wiring may be made of the same conductive material as the first wiring.

(Via 15)

The via 15 is provided in a hole penetrating the upper surface 111 and the lower surface 112 of the substrate 11, and electrically connects the first wiring and the second wiring. The via hole 15 may be composed of a fourth wiring 151 covering the surface of the through hole of the base material, and a filling member 152 filled in the fourth wiring 151. As the fourth wiring 151, the same conductive member as the first wiring, the second wiring, and the third wiring can be used. As the filling member 152, a conductive member or an insulating member may be used.

(insulating film 18)

The insulating film 18 is a member for ensuring insulation of the lower surface and preventing short circuit. The insulating film may be formed of any of the insulating films used in this field. Examples thereof include thermosetting resins and thermoplastic resins.

(first light-emitting element 20A, second light-emitting element 20B, and third light-emitting element 20C)

The first light-emitting element, the second light-emitting element, and the third light-emitting element are semiconductor elements which emit light by applying a voltage, and known semiconductor elements made of a nitride semiconductor or the like can be used. The first light-emitting element, the second light-emitting element, and the third light-emitting element include, for example, LED chips. The first light-emitting element, the second light-emitting element, and the third light-emitting element include at least a semiconductor layer, and in most cases, further include an element substrate. The first light emitting element, the second light emitting element, and the third light emitting element have positive and negative electrodes. The positive and negative electrodes may be made of gold, silver, tin, platinum, rhodium, titanium, aluminum, tungsten, palladium, nickel, or alloys thereof. As the semiconductor material, a nitride semiconductor is preferably used. Nitride semiconductor mainly uses In_xAl_yGa_1－x－yN (0 ≦ x, 0 ≦ y, x + y ≦ 1). In addition, inalgas-based semiconductors, InAlGaP-based semiconductors, zinc sulfide, zinc selenide, silicon carbide, and the like can also be used. The element substrate of the first light-emitting element, the second light-emitting element, and the third light-emitting element is mainly a crystal growth substrate capable of growing a crystal of a semiconductor constituting the semiconductor multilayer body, but may be a bonding substrate bonded to a semiconductor element structure separated from the crystal growth substrate. Since the element substrate has light-transmitting properties, flip-chip mounting is easy to perform, and light output efficiency is easy to improve. Examples of the base material of the element substrate include sapphire, gallium nitride, aluminum nitride, silicon carbide, gallium arsenide, gallium phosphide, indium phosphide, zinc sulfide, zinc oxide, zinc selenide, diamond, and the like. Among them, sapphire is preferable. The thickness of the element substrate may be appropriately selected, and is, for example, 0.02mm to 1mm, and is preferably 0.05mm to 0.3mm in terms of the strength of the element substrate and/or the thickness of the light-emitting device.

(first reflecting Member)

The first reflecting member is a member that suppresses absorption of light from the first light-emitting element by the substrate. The first reflecting member covers the upper surface of the base material and reflects light from the first light emitting element. In terms of light output efficiency of the light-emitting device, the light reflectance of the first reflecting member at the emission peak wavelength of the first light-emitting element is preferably 70% or more, more preferably 80% or more, and still more preferably 90% or more. The first reflecting member includes reflecting particles in a base material.

(base material of first reflecting member)

As the base material of the first reflecting member, a resin can be used, and examples thereof include a silicone resin, an epoxy resin, a phenol resin, a polycarbonate resin, an acrylic resin, and a modified resin thereof. Among them, the silicone resin and the modified silicone resin are preferable because they are excellent in heat resistance and light resistance. Specific examples of the silicone resin include dimethylsiloxane resin, phenylmethylsiloxane resin, and diphenylsiloxane resin.

(reflective particle)

The reflective particles may be one of titanium oxide, zinc oxide, magnesium carbonate, magnesium hydroxide, calcium carbonate, calcium hydroxide, calcium silicate, magnesium silicate, barium titanate, barium sulfate, aluminum hydroxide, aluminum oxide, zirconium oxide, and silicon oxide, or two or more of them may be used in combination. For example, reflective particles in which the surface of titanium oxide is coated with a known member such as zirconium oxide can be used as the reflective particles. The shape of the reflective particles may be appropriately selected, or may be irregular or broken, but is preferably spherical in view of fluidity. The particle size of the reflective particles is, for example, about 0.1 μm to about 0.5 μm, but the smaller the particle size, the better the effect of light reflection and coating. The content of the reflective particles in the light-reflective reflecting member can be appropriately selected, but is, for example, preferably 10 wt% to 80 wt%, more preferably 20 wt% to 70 wt%, and still more preferably 30 wt% to 60 wt%, in view of light reflectivity, viscosity in a liquid state, and the like.

(first covering Member)

The first covering member is a light-transmitting member that exposes the first light output surface and covers the first reflecting member and at least a part of the first side surface. As the first covering member, a light-transmitting member, for example, a resin may be used. Examples of the resin that can be used for the first covering member include a silicone resin, an epoxy resin, a phenol resin, a polycarbonate resin, an acrylic resin, and a modified resin thereof. Among them, the silicone resin and the modified silicone resin are preferable because they are excellent in heat resistance and light resistance.

The first coating member may contain various kinds of diffusion particles. Examples of the diffusion particles include silicon oxide, aluminum oxide, zirconium oxide, and zinc oxide. The diffusion particles may be used singly or in combination of two or more of them. Particularly preferred is silicon oxide having a small thermal expansion coefficient. Further, by using nanoparticles as the diffusion particles, the scattering of light emitted from the light-emitting element can be increased, and the amount of the wavelength conversion member used can be reduced. The nanoparticles are particles having a particle diameter of 1nm to 100 nm. The "particle diameter" in the present specification is, for example, D₅₀And (4) defining.

(component containing reflective particles)

The reflective particle-containing member is a member in which reflective particles are contained in a light-transmitting member. The reflective particle-containing member may include a reflective portion in which reflective particles are unevenly distributed, and a light-transmitting portion which is located above the reflective portion and in which the reflective particles are not unevenly distributed.

As the base material of the reflective particle-containing member, the same material as that of the first cladding member can be used. In addition, as the reflective particles of the reflective particle-containing member, the same material as the reflective particles of the first reflective member can be used.

(second coating Member)

The second covering member is a member covering at least a part of the first side surface. As the base material of the second covering member, the same material as that of the first covering member can be used.

(second reflecting Member)

The second reflecting member is a member surrounding the second covering member in a plan view. The second reflective member may use the same material as the first reflective member.

(translucent member 50)

The light-transmitting member covers the first light output surface and protects the first light-emitting element. As the base material of the light-transmissive member, the same material as the first cladding member can be used.

(adhesive layer 34)

The adhesive layer bonds the light transmissive member and the first light output surface of the first light emitting element. When the first light output surface is covered with the second covering member, the adhesive layer bonds the light-transmitting member and the second covering member. The adhesive layer has light transmittance. As the adhesive layer, the same material as the first covering member may be used.

(wavelength conversion member)

The wavelength conversion member absorbs at least a part of the primary light emitted from the light emitting element and emits secondary light having a wavelength different from that of the primary light. The wavelength conversion member may be used alone or in combination of two or more of the following specific examples. When the light-transmitting member includes a plurality of wavelength conversion layers, the wavelength conversion members included in the respective wavelength conversion layers may be the same or different.

Examples of the wavelength conversion member emitting green light include: yttrium-aluminum-garnet phosphor (e.g., Y)₃(Al，Ga)₅O₁₂: ce), lutetium aluminum garnet phosphor (e.g., Lu)₃(Al，Ga)₅O₁₂: ce), terbium aluminum garnet phosphor (e.g., Tb)₃(Al，Ga)₅O₁₂: ce-based phosphor and silicate-based phosphor (e.g., (Ba, Sr)₂SiO₄: eu), chlorosilicate based phosphor (e.g., Ca)₈Mg(SiO₄)₄Cl₂: eu) and beta sialon based phosphor (e.g., Si)_6－zAl_zO_zN_8－zEu (0 < z < 4.2), SGS-based phosphor (e.g., SrGa)₂S₄: eu), alkaline earth aluminate phosphor (Ba, Sr, Ca) Mg_xAl₁₀O_17－x: eu, Mn, etc. Examples of the wavelength conversion member emitting yellow light include: alpha sialon based phosphor (e.g., M)_z(Si，Al)₁₂(O，N)₁₆(wherein 0 < z ≦ 2, M is a lanthanide series other than Li, Mg, Ca, Y, and La and CeElements), and the like. Further, among the wavelength conversion members emitting green light, there are wavelength conversion members emitting yellow light. For example, the yttrium-aluminum garnet phosphor can shift the emission peak wavelength to the longer wavelength side by replacing a part of Y with Gd, and can emit yellow light. In addition, there is a wavelength conversion member capable of emitting orange light. As the red light-emitting wavelength conversion member, a nitrogen-containing calcium aluminosilicate (CASN or SCASN) -based phosphor (e.g., (Sr, Ca) AlSiN)₃: eu), and the like. Further, manganese-activated fluoride phosphors (represented by the general formula (1) A)₂[M_1－aMn_aF₆]A phosphor represented by the general formula (1) (wherein A is selected from the group consisting of K, Li, Na, Rb, Cs and NH₄At least one element selected from the group consisting of group 4 elements and group 14 elements, and a satisfies 0 < a < 0.2)). As a typical example of the manganese-activated fluoride-based phosphor, there is a phosphor of potassium fluosilicate activated with manganese (e.g., K)₂SiF₆：Mn)。

(method of manufacturing light emitting device 1000)

Next, an example of a method for manufacturing a light-emitting device according to the embodiment will be described with reference to fig. 11 to 18.

[ Process for preparing substrate and first light-emitting element ]

First, a substrate and a first light emitting element are prepared. The substrate is provided with: the circuit board comprises a substrate with an upper surface and a first wiring arranged on the upper surface. The first light emitting element has: the light source device includes a first light output surface, a first electrode forming surface located on an opposite side of the first light output surface, a first side surface located between the first light output surface and the first electrode forming surface, and a pair of first electrodes disposed on the first electrode forming surface. When the light-emitting device includes a plurality of light-emitting elements, the plurality of light-emitting elements are prepared. The step of preparing the substrate and the step of preparing the light-emitting element may be performed first. The substrate may be singulated for each light-emitting device, or may be in the state of an aggregate substrate before singulation.

[ Process for mounting the first light-emitting element ]

As shown in fig. 11, the first light-emitting element 20A is placed on the first wiring 12 such that the first electrode formation surface 203A of the first light-emitting element 20A faces the first wiring 12 of the substrate 10. The first wiring 12 and the

first electrodes

21A and 22A can be bonded by the conductive adhesive member 60. When the light-emitting device includes the second light-emitting element 20B, the second light-emitting element 20B is placed on the first wiring 12 such that the second electrode-formed surface 203B of the second light-emitting element 20B faces the first wiring 12 of the substrate 10.

[ Process for disposing reflective particle-containing Member ]

As shown in fig. 12, the reflective particle-containing member 30 is disposed on the upper surface 111 of the substrate 11 so that at least a part of the upper surface 111 of the substrate 11 overlapping with the first light-emitting element 20A is exposed in a plan view. By forming the reflective particle-containing member in which at least a part of the upper surface of the base material overlapping with the first light-emitting device is exposed in a plan view, the amount of reflective particle-containing member can be easily reduced as compared with the case of forming the reflective particle-containing member in which the upper surface of the base material overlapping with the first light-emitting device is not exposed. Thus, even after the step of spreading the reflective particle-containing member by centrifugal force, which will be described later, the reflective particle-containing member can be prevented from being formed on the first light output surface of the first light-emitting element. This facilitates the output of light from the first light-emitting element, thereby improving the light output efficiency of the light-emitting device.

The reflective particle-containing member 30 may be disposed in contact with the first side 202A of the first light-emitting element 20A, or may be disposed separately from the first side 202A of the first light-emitting element 20A. The reflective particle containing member 30 is preferably disposed so as to be separated from at least a part of the first side surface 202A. Thus, even after the step of spreading the reflective particle-containing member by centrifugal force, which will be described later, the reflective particle-containing member can be prevented from being formed on the first light output surface of the first light-emitting element. The entire first side surface may be spaced apart from the reflective particle-containing member.

As the reflective particle-containing member 30, a one-component thermosetting resin may be used, or a two-component thermosetting resin may be used. In the case of using a two-component thermosetting resin, it is preferable to mix the main agent and the reflective particles of the two-component thermosetting resin material, and after a lapse of a predetermined time or more, mix the curing agent. In this way, air located between the reflective particles and the primary agent can be discharged. This makes it easy to precipitate the reflective particles when a centrifugal force is applied, as described later. Examples of the two-component thermosetting resin material include silicone resin, modified silicone resin, epoxy resin, modified epoxy resin, and the like. The time elapsed after mixing the main agent of the two-component thermosetting resin material and the reflective particles is preferably 2 hours or more from the viewpoint of easier precipitation of the reflective particles. In addition, the time to elapse is preferably 8 hours or less from the viewpoint of shortening the manufacturing time. After the curing agent is mixed, the process proceeds to a step of spreading the reflective particle-containing member by centrifugal force before the reflective particle-containing member is cured.

[ Process for spreading reflective particle-containing Member by centrifugal force ]

The reflective particle containing member 30 is spread on the upper surface 111 of the base material 11 overlapping with the first light emitting element 20A by a centrifugal force. As shown in fig. 13, the intermediate body 100 including the substrate 10 and the reflective particle-containing member 30 is centrifugally rotated in a direction in which a centrifugal force is applied to the upper surface 111 of the base material 11. The intermediate body 100 shown in fig. 13 is a simplified diagram, and the intermediate body 100 may include a plurality of first light-emitting elements and/or second light-emitting elements. When the intermediate body 100 is rotated centrifugally, the intermediate body is rotated centrifugally about the rotating shaft 80 in which the upper surface 111 of the base material is located inward of the lower surface 112 of the base material. In other words, the rotation shaft 80 is positioned on the upper surface side of the intermediate body 100, and the intermediate body 100 is moved in the direction a revolving around the rotation shaft 80. The direction B in fig. 13 is a direction parallel to the upper surface 111 of the base material. By applying a centrifugal force to the reflective particle-containing member 30, the reflective particle-containing member 30 is expanded, and as shown in fig. 14, the upper surface 111 of the base material, which has been exposed from the reflective particle-containing member, can be covered with the reflective particle-containing member 30. This can suppress absorption of light from the first light-emitting element by the substrate, and improve the light output efficiency of the light-emitting device. At least a part of the upper surface 111 of the base material that has been exposed from the reflective particle-containing member before being coated with the reflective particle-containing member 30 may be coated, or the entire upper surface of the base material that overlaps with the first light-emitting element may be coated with the reflective particle-containing member 30. By covering the entire upper surface of the base material overlapping the first light-emitting element with the reflective particle-containing member 30, it is possible to further suppress absorption of light from the first light-emitting element into the substrate.

As shown in fig. 14, the first reflecting member 31 in which the reflecting particles are unevenly distributed and the first coating member 32 which is positioned on the first reflecting member 31 and has a lower concentration of the reflecting particles than the first reflecting member can be formed by forcibly precipitating the reflecting particles including the reflecting particle member 30 in the Z-negative direction by a centrifugal force. By covering the first side surface 202A of the first light-emitting element 20A with the first covering member 32, the light output efficiency of the light-emitting device is improved. The positive Z direction on the Z axis is a direction from the lower surface 112 of the base material 11 toward the upper surface 111 of the base material 11, and the opposite direction to the positive Z direction is a negative Z direction. The rotation speed or the rotation radius at which the intermediate body 100 is centrifugally rotated depends on the content of the reflective particles, the particle size, and the like, but for example, the rotation speed or the rotation radius may be adjusted so that a centrifugal force of 200xg or more is applied.

The intermediate body 100 may be singulated for each light-emitting device, or may be in the state of a collective substrate before being singulated. When the intermediate body is a collective substrate, the planar area of the intermediate body becomes large. When the planar area of the intermediate body is large, the difference in the manner of action of the centrifugal force tends to increase between the center of the intermediate body 100 and a position away from the center of the intermediate body 100. Therefore, there is a possibility that variations may occur in the shape of the reflective particle-containing member of each light-emitting device located at the center of the intermediate body 100 and at a position distant from the center of the intermediate body 100. The variation in the shape of the reflective particle-containing member can be suppressed by increasing the radius of rotation. Specifically, by providing a radius of rotation of 70 times or more the length of the intermediate body 100 arranged in the direction of rotation, it is possible to suppress the occurrence of variations in the shape of the reflective particle-containing member. Further, when the intermediate body has flexibility to flex along the circumference of the rotation radius due to the centrifugal force, the difference in distance from the rotation shaft 80 can be reduced.

When the reflective particle containing member 30 is cured, it is preferable to cure the reflective particle containing member while applying a centrifugal force to the reflective particle containing member. In terms of light reflection, it is preferable to use particles having a small particle size for the reflective particles, but the smaller the particle size, the more difficult the particles are to precipitate. The reflecting particles can be precipitated in the Z-negative direction by centrifugal force. In order to solidify the reflective particles in a state after deposition, it is preferable to perform the step of solidifying the member containing the reflective particles in a state in which a centrifugal force is applied (that is, while rotating the intermediate body 100). This can suppress the movement of the reflective particles in the positive Z-direction in the reflective particle-containing member.

The temperature for curing the reflective particle-containing member is, for example, 40 ℃ to 200 ℃. By increasing the curing temperature, the time for curing the reflective particle-containing member can be effectively shortened. In addition, when it is considered that the position of the rotating shaft 80 is moved by thermal expansion of the metal of the centrifugal precipitation device, the solidification temperature is preferably as low as possible. That is, the temperature for curing the reflective particle-containing member is preferably 50 ℃ or higher from the viewpoint of efficiency. In addition, the temperature for curing the reflective particle-containing member is preferably 60 ℃ or lower in consideration of the movement of the rotary shaft 80. When the solidification is carried out at 80 ℃ or higher, it is preferable to adjust the apparatus so that at least the metal portion of the centrifugal spinner does not become 80 ℃ or higher. As the resin material constituting the reflective particle-containing member, a resin material which is at least temporarily cured by holding the rotating intermediate body at a temperature of 40 ℃ or higher is preferably selected. Examples of the method of solidifying the reflective particle-containing member while precipitating the reflective particles include blowing hot air, and using a panel heater.

[ Process for Forming second covering Member ]

As shown in fig. 15, a second coating member 33 is formed to coat the reflective particle containing member 30. The second covering member 33 covers at least a part of the first side surface 202A of the first light-emitting element 20A. The second covering member 33 may cover the first light output surface 201 of the first light emitting element 20A, or may expose the first light output surface 201. In this step, the second coating member 33 is formed by dropping a liquid resin material containing a base material and a wavelength conversion member on the reflective particle containing member 30, for example. As another forming method, for example, the second coating member 33 is formed by adhering the wavelength conversion member to the member 30 containing reflective particles by a spray (mist) method, an electrodeposition method, or the like, and then dripping the base material to impregnate the phosphor with the same and curing the same. The wavelength conversion member may be unevenly distributed in a part of the second coating member or may be evenly dispersed in the second coating member.

[ Process for Forming translucent Member ]

As shown in fig. 16, the light-transmissive member 50 covering the first light output surface 201A of the first light-emitting element 20A is formed. The light-transmitting member may be prepared in advance, and then disposed on the first light output surface 201A to form a light-transmitting member covering the first light output surface 201A, or may be formed by a known method such as casting so as to cover the first light output surface 201A. When a light-transmitting member is disposed on the first light output surface 201A, the first light output surface 201A may be covered with a light-transmitting adhesive layer 34.

[ Process for Forming notches ]

As shown in fig. 17, a notch 70 is formed to penetrate the second coating member 33 and to contact at least the reflective particle-containing member 30. The notch 70 is formed so as to surround the first light-emitting element 20A in a plan view. When the light-emitting device includes the second light-emitting element 20B, the notch 70 is formed so as to surround the first light-emitting element 20A and the second light-emitting element 20B in a plan view. When the reflective particle-containing member 30 includes the first reflective member 31 in which the reflective particles are unevenly distributed and the first coating member 32 which is positioned on the first reflective member 31 and in which the concentration of the reflective particles is lower than that of the first reflective member, the notch 70 penetrates the first reflective member 32 and the second coating member 33, and the notch 70 which is in contact with at least the first reflective member 31 is formed. The notch 70 may or may not penetrate the first reflecting member 31. In addition, when the notch 70 penetrates the first reflecting member 31, the notch 70 may be in contact with the upper surface 111 of the base material. The notch in the upper surface 111 of the substrate 11 is referred to as a recess 118. When the light-emitting device includes the light-transmissive member 50, the notch 70 is formed so as to penetrate the light-transmissive member 50. For example, the notch may be formed by a known method such as a blade cutting method or a laser cutting method. In this specification, a portion formed by etching is referred to as a notch. The notch has a narrow width portion and a wide width portion, the narrow width portion is located on the negative Z direction side, and the wide width portion is located on the positive Z direction side. The narrow width portion and the wide width portion may be formed by the shape of the blade or the like.

[ Process for Forming second reflective Member ]

As shown in fig. 18, the second reflecting member 40 is formed in contact with the second coating member 33 and the reflective particle-containing member 30. The second reflecting member 40 surrounds the first light emitting element 20A in a plan view. When the light-emitting device includes the second light-emitting element 20B, the second reflecting member 40 surrounds the first light-emitting element 20A and the second light-emitting element 20B in a plan view. The second reflective member 40 may be formed by filling the second reflective member before curing in the gap 70 and then curing the second reflective member before curing. As a method of filling the gap 70 with the second reflective member before curing, a known method such as transfer molding, injection molding, compression molding, or casting may be used. In order to adjust the thickness to a desired value, a part of the second reflecting member 40 may be removed by a known method such as grinding. When the light-emitting device includes the light-transmitting member, the second reflecting member may be formed so as to cover the upper surface and/or the side surface of the light-transmitting member. When the second reflective member covering the entire upper surface of the light-transmissive member is formed, a part of the second reflective member is removed so that at least a part of the light-transmissive member is exposed from the second reflective member. When a part of the second reflecting member is removed to adjust the thickness of the second reflecting member 40 to a desired thickness, a part of the translucent member may be removed. When a part of the second reflecting member and a part of the light-transmitting member are removed, the upper surface of the second reflecting member and the upper surface of the light-transmitting member may be flush with each other.

[ step of obtaining a chip ]

When the intermediate body 100 is in the state of an aggregate substrate, as shown in fig. 18, the second reflecting member 40 and a part of the substrate 10 are removed along the broken lines S3 and S4, and the light emitting devices are singulated. For example, the second reflecting member 40 and the substrate 10 may be cut by a dicing method, a laser cutting method, or the like, thereby singulating the light emitting devices.

As described above, the light-emitting device 1000 is manufactured by performing the above steps.

Industrial applicability of the invention

The light-emitting device according to one embodiment of the present invention can be used for a backlight device of a liquid crystal display, various lighting apparatuses, a large-sized display, various display devices such as an advertisement and a signpost, a projector device, and an image reading device in a digital camera, a facsimile machine, a copier, a scanner, and the like.

Claims

1. A light-emitting device is characterized by comprising:

a substrate including a base material having an upper surface and a first wiring disposed on the upper surface;

a first light emitting element having: a first light output surface, a first electrode forming surface located on the opposite side of the first light output surface, a first side surface located between the first light output surface and the first electrode forming surface, and a pair of first electrodes provided on the first electrode forming surface, the first electrode forming surface and the first wirings being placed on the first wirings so as to face each other;

a first reflecting member that exposes the first light output surface, covers the upper surface of the substrate, and contains reflective particles;

a first covering member that exposes the first light output surface, covers the first reflecting member and at least a part of the first side surface, and has a lower concentration of the reflective particles than the first reflecting member;

a second covering member covering at least a part of the first side surface;

a second reflecting member that surrounds the second covering member in a plan view and is in contact with the second covering member and the first reflecting member,

the second reflecting member has a narrow portion that contacts the first reflecting member in cross section, and a wide portion that is arranged above the narrow portion.

2. The light-emitting apparatus according to claim 1,

the light-emitting device is provided with a second light-emitting element having a light-emission peak wavelength different from that of the first light-emitting element.

3. The light-emitting apparatus according to claim 1 or 2,

the first cladding member is in contact with the second reflective member.

4. The lighting device according to claim 3,

the thickness of the first cladding member of a portion in contact with the first light emitting element is thicker than the thickness of the first cladding member of a portion in contact with the second reflecting member.

5. The light-emitting device according to any one of claims 1 to 4,

the upper surface of the base material has a recess surrounding the outer periphery, and a part of the second reflecting member is disposed in the recess.

6. The light-emitting device according to any one of claims 1 to 5,

the outer edge of the substrate is flush with the outer side surface of the second reflecting member.

7. The light-emitting device according to any one of claims 1 to 6,

the first light-emitting element includes a first semiconductor layer, and a side surface of the first semiconductor layer is covered with the first reflecting member.

8. The light-emitting device according to any one of claims 1 to 7,

the light-transmitting member covers the first light output surface.

9. A method for manufacturing a light-emitting device, comprising:

a step of preparing a substrate having a base material having an upper surface and a first wiring disposed on the upper surface;

a step of preparing a first light-emitting element having: a first light output surface, a first electrode forming surface located on the opposite side of the first light output surface, a first side surface located between the first light output surface and the first electrode forming surface, and a pair of first electrodes provided on the first electrode forming surface;

a step of mounting a first light-emitting element on the first wiring so that the first electrode formation surface faces the first wiring;

disposing a reflective particle-containing member on the upper surface of the base material such that at least a part of the upper surface of the base material overlapping the first light-emitting element is exposed in a plan view;

and spreading the reflective particle-containing member on the upper surface of the base material overlapping the first light-emitting element by a centrifugal force.

10. The method of manufacturing a light emitting device according to claim 9,

in the step of spreading the reflective particle-containing member by a centrifugal force, the entire upper surface of the base material overlapping the first light-emitting element is covered with the reflective particle-containing member.

11. The method of manufacturing a light emitting device according to claim 9 or 10,

the method includes a step of forming a second coating member that coats the reflective particle-containing member after the step of spreading the reflective particle-containing member by centrifugal force.

12. The method of manufacturing a light emitting device according to claim 11,

the method further includes a step of forming a second reflecting member that surrounds the first light emitting element in a plan view and is in contact with the second coating member and the reflective particle-containing member, after the step of forming the second coating member.

13. The method of manufacturing a light emitting device according to claim 12,

the method includes a step of removing a part of the second reflecting member and the substrate to singulate the substrates.