Light-emitting device

Abstract

To provide a light-emitting device that excels in the efficiency of extracting light.SOLUTION: Provided is a light-emitting device 100 comprising: a first section 10 including a light-emitting element 12, a wavelength conversion member 13 located on the top face of the light-emitting element, and a first reflection member 11 for covering side faces of the light-emitting element and side faces of the wavelength conversion member; and a second section 20 including a translucent member 22 located upward of the wavelength conversion member via an air layer 60, and a second reflection member located in the periphery of the translucent member. The top face of the first reflection member includes a first top face located in the periphery of the wavelength conversion member, and a second top face located in the periphery of the first top face, and the underside of the second reflection member includes a first underside located in the periphery of the translucent member, and a second underside located in the periphery of the first underside. The air layer is located between the first top face of the first reflection member and the first underside of the second reflection member.SELECTED DRAWING: Figure 1B

Description

Technical Field

[0001] The present disclosure relates to a light-emitting device.

Background Art

[0002] A structure in which a light-transmitting member is disposed via an air layer on a wavelength conversion member is known (for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Further improvement in light extraction efficiency is required.

Means for Solving the Problems

[0005] An embodiment of the present invention includes the following configuration. A first part including a light-emitting element, a wavelength conversion member disposed on an upper surface of the light-emitting element, and a first reflecting member covering a side surface of the light-emitting element and a side surface of the wavelength conversion member; A second part including a light-transmitting member disposed via an air layer above the wavelength conversion member and a second reflecting member disposed around the light-transmitting member; and an upper surface of the first reflecting member has a first upper surface disposed around the wavelength conversion member and a second upper surface disposed around the first upper surface; a lower surface of the second reflecting member has a first lower surface disposed around the light-transmitting member and a second lower surface disposed around the first lower surface; the air layer is also disposed between the first upper surface of the first reflecting member and the first lower surface of the second reflecting member, a light-emitting device.

Effects of the Invention

[0006] As described above, a light-emitting device excellent in light extraction efficiency can be provided.

Brief Description of the Drawings

[0007]

Figure 1A

Figure 1B

Figure 1C

Figure 2A

Figure 2B

Figure 2C

Figure 3A

Figure 3B

Figure 4A

Figure 4B

Figure 5A

Figure 5B

Figure 6

Figure 7

Figure 8

Figure 9

Embodiments for Carrying Out the Invention

[0008] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following description, terms indicating specific directions and positions (for example, "up", "down", and other terms including those terms) are used as necessary. The use of these terms is for facilitating the understanding of the invention with reference to the drawings, and the technical scope of the present invention is not limited by the meanings of those terms.

[0009] Also, parts denoted by the same reference numerals in a plurality of drawings indicate the same or equivalent parts or members. Furthermore, the embodiments shown below exemplify a light-emitting device for embodying the technical idea of the present invention, and do not limit the present invention below. Also, the dimensions, materials, shapes, relative arrangements, etc. of the constituent members described below are not intended to limit the scope of the present invention only thereto without specific description, but are intended to be exemplified. Also, the content described in one embodiment or example is applicable to other embodiments or examples. Also, the sizes and positional relationships of the members shown in the drawings may be exaggerated for clarity of explanation. Also, "plan view" means viewing directly or through perspective from the upper surface side or the lower surface side of the light-emitting device. Also, "cross-sectional view" means a cross-section in a cut surface passing through the center of the light-emitting device in plan view, and viewing a cross-section including a first part and a second part. Also, the side closer to the center of the light-emitting device in plan view is defined as the inner side, and the side closer to the side surface of the light-emitting device is defined as the outer side. Also, an end view showing only the cut surface may be used as a cross-sectional view.

[0010] The light-emitting device according to the embodiment includes a first part including a light-emitting element, a wavelength conversion member disposed on the upper surface of the light-emitting element, and a first reflecting member that covers the side surface of the light-emitting element and the side surface of the wavelength conversion member, and a second part including a light-transmitting member disposed above the wavelength conversion member with an air layer therebetween and a second reflecting member disposed around the light-transmitting member. The upper surface of the first reflecting member has a first upper surface disposed around the wavelength conversion member and a second upper surface disposed around the first upper surface. The lower surface of the second reflecting member has a first lower surface disposed around the light-transmitting member and a second lower surface disposed around the first lower surface. And the air layer is also disposed between the first upper surface of the first reflecting member and the first lower surface of the second reflecting member. That is, the air layer is disposed not only between the upper surface of the wavelength conversion member and the lower surface of the light-transmitting member but also between the first upper surface of the first reflecting member and the second lower surface of the second reflecting member. In other words, the air layer is in contact with the upper surface of the wavelength conversion member of the first part and the first upper surface of the first reflecting member, and is in contact with the lower surface of the light-transmitting member of the second part and the first lower surface of the second reflecting member.

[0011] The wavelength conversion member is located above the light-emitting element, and the light-transmitting member is located above the wavelength conversion member with an air layer therebetween. A part of the light (first light) emitted from the light-emitting element and taken out from the upper surface of the wavelength conversion member passes through the air layer and is incident on the light-transmitting member, and then is taken out to the outside. A part of the first light is reflected by the first lower surface of the second reflecting member disposed around the light-transmitting member and travels downward (second light). The second light passes through the air layer again and then is irradiated onto the upper surface of the wavelength conversion member and the first upper surface of the first reflecting member disposed around the wavelength conversion member. A part of the second light is wavelength-converted by the wavelength conversion member and then travels upward again, and the other part of the second light is reflected by the first upper surface of the first reflecting member and travels upward and is taken out from the light-transmitting member to the outside. Thus, by repeatedly reflecting the light by the first lower surface and the first upper surface, the light can be efficiently taken out from the light-transmitting member to the outside. Also, since a part of the second light reflected by the first lower surface is wavelength-converted by the wavelength conversion member, the wavelength conversion efficiency can be improved. Thereby, the amount of the wavelength conversion substance contained in the wavelength conversion member can be reduced.

[0012] The shape of the light-emitting device is a cube or a rectangular parallelepiped. As the rectangular parallelepiped, it can be a rectangular parallelepiped that is long in the vertical direction or a rectangular parallelepiped that is long in the horizontal direction. In such a case, the shape of the light-emitting device in plan view is a square or a rectangle. That is, the first part and the second part have the same size and the same shape. However, not limited to this, the shape of the light-emitting device can be a cylindrical shape, an elliptical cylinder shape, or a frustum of a cone shape in addition to a cube or a rectangular parallelepiped. The size of the light-emitting device can be, for example, when the shape in plan view is a quadrilateral, the length of one side can be 1 mm to 10 mm, and the height can be 0.2 mm to 5 mm.

[0013] Hereinafter, each component of the light-emitting device according to the embodiment will be described in detail with reference to the drawings.

[0014] <Embodiment 1> An example of the light-emitting device 100 according to Embodiment 1 is shown in FIGS. 1A to 1C. The light-emitting device 100 includes a first part 10 and a second part 20 disposed above the first part 10. Further, in Embodiment 1, the light-emitting device 100 includes the first part 10, the second part 20, and a third part 30 disposed between them. An air layer 60 is disposed in a space surrounded by the upper surface of the first part 10, the lower surface of the second part 20, and the inner surface 30M of the third part 30. The first part 10 and the third part 30 are joined by a joining member 40. Similarly, the second part 20 and the third part 30 are joined by a joining member 40. The light-emitting device 100 further includes a substrate 50 that is electrically connected to the light-emitting element 12 via a conductive connecting member such as solder. Note that the substrate 50 can be omitted.

[0015] The first part 10 includes a light-emitting element 12, a wavelength conversion member 13 disposed on the upper surface of the light-emitting element 12, and a first reflecting member 11 that covers the side surfaces of the light-emitting element 12 and the wavelength conversion member 13. The second part 20 includes a light-transmitting member 22 and a second reflecting member 21 disposed around the light-transmitting member 22. The third part 30 includes a third reflecting member 31.

[0016] (The first part) The first part 10 includes a light-emitting element 12, a wavelength conversion member 13 disposed on the upper surface of the light-emitting element 12, and a first reflecting member 11 that covers the side surface of the light-emitting element 12 and the side surface of the wavelength conversion member 13. Further, the first part 10 can include a light-transmissive light guide member 15 disposed between the light-emitting element 12 and the wavelength conversion member 13 and joining them. The light guide member 15 may be provided between the light-emitting element 12 and the covering member 14. Furthermore, when the light-emitting device 100 includes a substrate 50, it can include a covering member 14 disposed between the light-emitting element 12 and the substrate 50. The light emitted from the light-emitting element 12 is incident on the air layer 60 through the wavelength conversion member 13.

[0017] The light-emitting element 12 includes a semiconductor laminate 121 and a pair of positive and negative electrodes 122. The wavelength conversion member 13 is disposed directly or via the light guide member 15 on the upper surface of the semiconductor laminate 121. The first reflecting member 11 covers the side surface of the wavelength conversion member 13 and the side surface of the light-emitting element 12. When the light guide member 15 and / or the covering member 14 is provided on the side of the light-emitting element 12, the first reflecting member 11 indirectly covers the side surface of the light-emitting element 12 via the light guide member 15 and / or the covering member 14. The upper surface of the wavelength conversion member 13 and the upper surface of the first reflecting member 11 constitute the upper surface of the first part 10 and are surfaces facing the lower surface of the second part 20. The side surface (outer surface) 11S of the first reflecting member 11 is the side surface of the first part 10 and constitutes a part of the side surface of the light-emitting device 100. When the substrate 50 is included, the first reflecting member 11 covers the upper surface of the substrate 50. Also, when the covering member 14 is not provided, the first reflecting member 11 is also disposed between the upper surface of the substrate 50 and the lower surface of the light-emitting element 12.

[0018] The upper surface 11U of the first reflecting member 11 includes a first upper surface 11U1 and a second upper surface 11U2. The first upper surface 11U1 is located outside, that is, on the outer periphery of the wavelength conversion member 13 in plan view, and the second upper surface 11U2 is located at least on the outer periphery, that is, outside of the first upper surface 11U1. The first upper surface 11U1 is the surface in contact with the air layer 60. The second upper surface 11U2 is in contact with the joining member 40 and is a surface not in contact with the air layer 60. The area of the first upper surface 11U1 on the upper surface 11U of the first reflecting member 11 can be, for example, 10% to 60% of the area of the upper surface 11U. The shape and size of the second upper surface 11U2 of the first reflecting member 11 substantially coincide with the shape and size of the lower surface of the third portion 30. Immediately above the first upper surface 11U1 of the first reflecting member 11, at least the first lower surface 21D1 of the second reflecting member 21 is disposed via the air layer 60. Note that immediately above the first upper surface 11U1 of the first reflecting member 11, the first lower surface 21D1 of the second reflecting member 21 and the lower surface 22D of the light transmissive member 22 may be disposed via the air layer 60.

[0019] Figures 2A to 2C are diagrams showing an arrangement example of the first upper surface 11U1 and the second upper surface 11U2 on the upper surface 11U of the first portion 10. In the examples shown in Figures 2A to 2C, the upper surface 11U of the first reflecting member 11 is disposed around the entire upper surface 13U of the wavelength conversion member 13, that is, on the entire circumference. Here, an example in which the planar shape of the first portion 10 is a quadrangle is shown, and the upper surface 11U of the first reflecting member 11 is an annular shape with a quadrangular inner periphery and outer periphery. The width (distance between the inner periphery and the outer periphery) of the upper surface 11U of the first reflecting member 11 may be the same, or may be partially different widths. Note that Figures 2A to 2C are also diagrams showing an arrangement example of the first lower surface 21D1 and the second lower surface 21D2 on the lower surface 21D of the second portion 20 described later.

[0020] In the example shown in FIG. 2A, the upper surface 11U of the first reflecting member 11 has a first upper surface 11U1 disposed entirely around the wavelength conversion member 13 and a second upper surface 11U2 disposed entirely around the first upper surface 11U1, that is, disposed entirely around the perimeter. In other words, in a plan view, the upper surface 13U of the wavelength conversion member 13 is located in the central region of the first portion 10, the first upper surface 11U1 of the first reflecting member 11 is located outside thereof, and the second upper surface 11U2 is located further outside thereof. The second upper surface 11U2 of the first reflecting member 11 is not located inside the first upper surface 11U1.

[0021] In the examples shown in FIGS. 2B and 2C, the upper surface 11U of the first reflecting member 11 includes a plurality of second upper surfaces 11U2. In the example shown in FIG. 2B, the first upper surface 11U1 and the second upper surfaces 11U2 are located on two opposing sides (the left and right sides in FIG. 2B). That is, the second upper surfaces 11U2 are disposed in two separate portions. Also, on the two sides (the upper and lower sides in FIG. 2B) sandwiched by the two sides (the left and right sides in FIG. 2B), only the first upper surface 11U1 is disposed in the portion excluding both ends.

[0022] In the example shown in FIG. 2C, at the four corners, the second upper surfaces 11U2 are located outside the first upper surface 11U1. That is, the second upper surfaces 11U2 are disposed in four separate portions.

[0023] The first upper surface 11U1 and the second upper surface 11U2 of the first reflecting member 11 can be located on the same plane, like the first portion 10A shown in FIG. 1B or the like. Also, like the first portion 10B shown in FIG. 3A, the second upper surface 11U2 can be located below the first upper surface 11U1. In other words, the first reflecting member 11 can include a first recess 11R that is a recess concave downward from the first upper surface 11U1 and has the second upper surface 11U2 as the lowermost surface (bottom surface).

[0024] Alternatively, like the first portion 10C shown in FIG. 3B, the second upper surface 11U2 can be positioned above the first upper surface 11U1. In other words, the first reflecting member 11 can be a convex portion that protrudes above the first upper surface 11U1, and can include a first convex portion 11P having the second upper surface 11U2 as the uppermost surface (top surface).

[0025] The upper surface 11U of the first reflecting member 11 of the first portion 10 may include only one of the first convex portion 11P or the first concave portion 11R, or may include both. In other words, it can include only the second upper surface 11U2 disposed at a position higher than the first upper surface 11U1, or only the second upper surface 11U2 disposed at a position lower than the first upper surface 11U1. Alternatively, it can include both the second upper surface 11U2 disposed at a position higher than the first upper surface 11U1 and the second upper surface 11U2 disposed at a position lower than the first upper surface 11U1. For example, as shown in FIG. 2A, when the second upper surface 11U2 is disposed all around, i.e., on the entire circumference, of the first upper surface 11U1, the second upper surface 11U2 is positioned at a position higher than the first upper surface 11U1 on two opposing sides (the left and right sides in FIG. 2A), and the second upper surface 11U2 can be positioned at a position lower than the first upper surface 11U1 on two sides (the upper and lower sides in FIG. 2A) sandwiched by the two sides (the left and right sides in FIG. 2A).

[0026] (Second portion) The second portion 20 includes a light-transmissive member 22 and a second reflecting member 21 disposed around the light-transmissive member. The upper surface 22U of the light-transmissive member 22 and the upper surface 21U of the second reflecting member 21 are part of the upper surface of the second portion 20 and are surfaces that are part of the upper surface of the light-emitting device 1. The light-transmissive member 22 is a portion that serves as the light extraction surface of the light-emitting device 100. The second reflecting member 21 is a member that holds the light-transmissive member 22. The side surface 21S of the second reflecting member 21 constitutes the side surface of the second portion 20 and constitutes part of the side surface of the light-emitting device 100. The lower surface 22D of the light-transmissive member 22 and the lower surface 21D of the second reflecting member 21 constitute the lower surface of the second portion 20 and are surfaces that face the upper surface of the first portion 10.

[0027] The lower surface 21D of the second reflecting member 21 includes a first lower surface 21D1 and a second lower surface 21D2. The first lower surface 21D1 is located outside, that is, on the outer periphery of the light-transmitting member 22 in a plan view. The second lower surface 21D2 of the second reflecting member 21 is located at least outside, that is, on the outer periphery of the first lower surface 21D1. The first lower surface 21D1 is a surface in contact with the air layer 60. The second lower surface 21D2 is in contact with the joining member 40 and is a surface not in contact with the air layer 60. The area of the first lower surface 21D1 on the lower surface 21D of the second reflecting member 21 can be, for example, 10% to 60% of the area of the lower surface 21D. The shape and size of the second lower surface 21D2 substantially match the shape and size of the upper surface of the third portion 30. Immediately below the first lower surface 21D1 of the second reflecting member 21, the first upper surface 11U1 of the first reflecting member 11 is disposed via the air layer 60. Note that immediately below the first lower surface 21D1 of the second reflecting member 21, the first upper surface 11U1 of the first reflecting member 11 and the upper surface 13U of the wavelength conversion member 13 may be disposed via the air layer 60.

[0028] Figs. 2A to 2C are diagrams showing an arrangement example of the first lower surface 21D1 and the second lower surface 21D2 on the lower surface 21D of the second portion 20. In the examples shown in Figs. 2A to 2C, the lower surface 21D of the second reflecting member 21 is disposed around the entire lower surface 22D of the light-transmitting member 22, that is, on the entire circumference. Here, an example in which the planar shape of the second portion 20 is a quadrangle is shown, and the lower surface 21D of the second reflecting member 21 is an annular shape with a quadrangular inner periphery and outer periphery. The width (distance between the inner periphery and the outer periphery) of the lower surface 21D of the second reflecting member 21 may be the same, or may be partially different widths.

[0029] In the example shown in Fig. 2A, the lower surface 21D of the second reflecting member 21 has a first lower surface 21D1 disposed around the entire light-transmitting member 22, that is, on the entire circumference, and a second lower surface 21D2 disposed around the entire first lower surface 21D1, that is, on the entire circumference. In other words, in a plan view, the lower surface 22D of the light-transmitting member 22 is located in the central region of the second portion 20, the first lower surface 21D1 of the second reflecting member 21 is located outside thereof, and the second lower surface 21D2 is located further outside thereof. The second lower surface 21D2 of the second reflecting member 21 is not located inside the first lower surface 21D1.

[0030] In the examples shown in FIGS. 2B and 2C, the lower surface 21D of the second reflecting member 21 includes a plurality of second lower surfaces 21D2. In the example shown in FIG. 2B, the first lower surface 21D1 and the second lower surfaces 21D2 are located on two opposite sides (the left and right sides in FIG. 2B). That is, the second lower surfaces 21D2 are arranged in two separate portions. Also, on the two sides (the upper and lower sides in FIG. 2B) sandwiched by the two sides (the left and right sides in FIG. 2B), only the first lower surface 21D1 is arranged in the portion excluding both ends.

[0031] In the example shown in FIG. 2C, at the four corners, the second lower surfaces 21D2 are located outside the first lower surface 21D1. That is, the second lower surfaces 21D2 are arranged in four separate portions.

[0032] The first lower surface 21D1 and the second lower surfaces 21D2 of the second reflecting member 21 can be located on the same plane, like the second portion 20A shown in FIG. 1B and the like. Also, like the second portion 20B shown in FIG. 4A, the second lower surfaces 21D2 can be located above the first lower surface 21D1. In other words, the second reflecting member 21 can be a recessed portion that is recessed above the first lower surface 21D1 and includes a second recess 21R having the second lower surfaces 21D2 as the uppermost surface (ceiling surface).

[0033] Alternatively, like the second portion 20C shown in FIG. 4B, the second lower surfaces 21D2 can be located below the first lower surface 21D1. In other words, the second reflecting member 21 can be a convex portion that protrudes below the first lower surface 21D1 and includes a second convex portion 21P having the second lower surfaces 21D2 as the lowermost surface.

[0034] The lower surface 21D of the second reflecting member 21 of the second part 20 may include only one of the second convex portion 21P and the second concave portion 21R, or may include both. In other words, it can include only the second lower surface 21D2 disposed at a position higher than the first lower surface 21D1, or only the second lower surface 21D2 disposed at a position lower than the first lower surface 21D1. Alternatively, it can include both the second lower surface 21D2 disposed at a position higher than the first lower surface 21D1 and the second lower surface 21D2 disposed at a position lower than the first lower surface 21D1. For example, as shown in FIG. 2A, when the second lower surface 21D2 is disposed around the entire circumference of the first lower surface 21D1, i.e., on the entire circumference, the second lower surface 21D2 is located at a position higher than the first lower surface 21D1 on two opposing sides (the left and right sides in FIG. 2A), and the second lower surface 21D2 can be located at a position lower than the first lower surface 21D1 on the two sides (the upper and lower sides in FIG. 2A) sandwiched between the two sides (the left and right sides in FIG. 2A).

[0035] (Section 3) The third part 30 is disposed between the second upper surface 11U2 of the first reflecting member 11 of the first part 10 and the second lower surface 21D2 of the second reflecting member 21 of the second part 20 via a joining member 40. That is, the upper surface of the third part 30 is joined to the second lower surface 21D2 of the second reflecting member 21 of the second part 20, and the lower surface of the third part 30 is joined to the second upper surface 11U2 of the first reflecting member 11 of the first part 10. The side surface (outer surface) 30S of the third part 30 constitutes a part of the side surface of the light emitting device 100. Also, the side surface (inner surface) 30M of the third part 30 is in contact with the air layer 60.

[0036] In a plan view, the shape of the lower surface 30D of the third part 30 coincides with the shape of the second upper surface 11U2 of the first reflecting member 11 of the first part 10. Also, in a plan view, the shape of the upper surface 30U of the third part 30 coincides with the shape of the second lower surface 21D2 of the second reflecting member 21 of the second part 20. When the inner and outer circumferences of the second upper surface 11U2 of the first reflecting member 11 are in the shape of a quadrangular ring, the shape of the third part 30 in a plan view can be a quadrangular-ring shape with inner and outer circumferences, as shown in FIG. 5A. In the case of such a shape, the light-emitting device 100 includes one third part 30. When the second upper surface 11U2 of the first reflecting member 11 is arranged in a part around the first upper surface 21U as shown in FIG. 2B or FIG. 2C, that is, when there are a plurality of second upper surfaces 21U2, a plurality of columnar or wall-like third parts 30 can be provided. When a plurality of third parts 30 are provided, a part of the first reflecting member 11 of the first part 10 or a part of the second reflecting member 21 of the second part 20 can be arranged between adjacent third parts 30. Alternatively, an air layer 60 may be provided between adjacent third parts 30, that is, the air layer 60 may communicate with the outside. In such a case, for example, the air layer thermally expanded by heat generation due to driving of the light-emitting device can be discharged to the outside. Thereby, breakage of the second part 20 can be reduced.

[0037] As shown in FIG. 3A, in the case of the first part 10B where the second upper surface 11U2 of the first reflecting member 11 is located below the first upper surface 11U1, that is, when the first reflecting member 11 includes a first concave portion 11R that is recessed downward, the third part 30 is arranged on the second upper surface 11U2 located within the first concave portion 11R. In this case, the height of the third part 30 needs to be higher than the depth of the first concave portion 11R. Also, as shown in FIG. 3B, when the second upper surface 11U2 of the first reflecting member 11 is located above the first upper surface 11U1, that is, when the first reflecting member 11 includes a first convex portion 11P that protrudes upward, the third part 30 is arranged on the second upper surface 11U2 that is the upper surface of the first convex portion 11P.

[0038] As shown in FIG. 4A, when the second lower surface 21D2 of the second reflecting member 21 is located above the first lower surface 21D1, that is, when the second reflecting member 21 includes a second concave portion 21R that is recessed upward, the third portion 30 is disposed below the second lower surface 21D2 that is the upper surface (ceiling surface) of the second concave portion 21R. In this case, the height of the third portion 30 needs to be higher than the depth of the second concave portion 21R. Further, as shown in FIG. 4B, when the second lower surface 21D2 of the second reflecting member 21 is located below the first lower surface 21D1, that is, when the second reflecting member 21 includes a second convex portion 21P that protrudes downward, the third portion 30 is disposed below the second lower surface 21D2 that is the lower surface of the second convex portion 21P.

[0039] (Bonding member) The bonding member 40 is disposed between the first portion 10 and the third portion 30, and between the second portion 20 and the third portion 30, and bonds them respectively. Specifically, the bonding member 40 is disposed between the second upper surface 11D2 of the first reflecting member 11 of the first portion 10 and the lower surface 30D of the third portion 30. Also, the bonding member 40 is disposed between the second lower surface 21D2 of the second reflecting member 21 of the second portion 20 and the upper surface 30U of the third portion 30. When the upper surface 11U of the first reflecting member 11 of the first portion 10 includes a first concave portion 11R, the bonding member 40 can also be disposed between the side surface defining the first concave portion 11R and the side surface (inner side surface) 30M of the third portion 30. Similarly, when the lower surface 21D of the second reflecting member 21 of the second portion 20 includes a second concave portion 21R, the bonding member 40 can also be disposed between the side surface defining the second concave portion 20R and the side surface (inner side surface) 30M of the third portion 30.

[0040] The third portion 30 includes a third reflecting member 31. The third portion 30A shown in FIG. 5A is composed of only the third reflecting member 31. The third portion 30B shown in FIG. 5B may be composed of a base 32 and the third reflecting member 31. In this case, the third reflecting member 31 is disposed at least on the side in contact with the air layer 60, that is, the inner side surface 30M side. Also, the third reflecting member 31 may be disposed on a surface other than the inner side surface side of the base 32.

[0041] (Air layer) The air layer 60 is disposed between the upper surface 13U of the wavelength conversion member 13 of the first portion 10 and the lower surface 22D of the light transmissive member 22 of the second portion 20. In addition to this, the air layer 60 is also disposed between the first upper surface 11U1 of the first reflecting member 11 of the first portion 10 and the first lower surface 21D1 of the second reflecting member 21 of the second portion 20. In other words, the air layer 60 is in contact with the upper surface 13U of the wavelength conversion member 13 and the first upper surface 11U1 of the first reflecting member 11 of the first portion 10, and is in contact with the lower surface 22D of the light transmissive member 22 and the first lower surface 21D1 of the second reflecting member 21 of the second portion 20, and is further disposed so as to be in contact with the inner surface 30M of the third portion 30.

[0042] The thickness of the air layer 60, that is, the distance between the upper surface 13U of the wavelength conversion member 13 and the lower surface 22D of the light transmissive member 22, can be, for example, 10 μm to 500 μm.

[0043] The first portion 10, the second portion 20, and the third portion 30 may be combined in any of the above-described shapes. For example, as shown in FIG. 1B, by combining the first portion 10A having a flat upper surface, the second portion 20A having a flat lower surface, and the third portion 30A including only the third reflecting member 31, the light emitting device 100 can be formed relatively easily. Further, by using the first portion 10B (FIG. 3A) having the first recess 11R on the upper surface or the second portion 20B (FIG. 4A) having the second recess 21R on the lower surface, the third portion 30 can be disposed in these recesses, and the adhesion can be improved. Combinations other than these can also be used.

[0044] <Embodiment 2> The light-emitting device according to Embodiment 2 includes a first portion 10 and a second portion 20 disposed above the first portion 10. In Embodiment 2, it is different from Embodiment 1 in that it does not include a third portion. Further, in Embodiment 2, as a combination of the first portion 10 and the second portion 20, either the first portion 10C (FIG. 3B) having the first convex portion 11P on the upper surface 11U of the first reflecting member 11 or the second portion 20C (FIG. 4B) having the second convex portion 21P on the lower surface 21D of the second reflecting member 21 is essential. By providing a convex portion on either the first portion 10 or the second portion 20, an air layer 60 can be disposed between the first portion 10 and the second portion 20.

[0045] The light-emitting device 100B shown in FIG. 6 includes a first portion 10B in which the second upper surface 11U2 of the first reflecting member 11 is located below the first upper surface 11U1 as shown in FIG. 3A. That is, the first portion 10B includes the first concave portion 11R. And it includes a second portion 20C in which the second lower surface 21D2 of the second reflecting member 21 is located below the first lower surface 21D1 as shown in FIG. 4B. That is, the second portion 20C includes the second convex portion 21P. The height of the second convex portion 21P (the distance between the first lower surface 21D1 and the second lower surface 21D2) is greater than the depth of the first concave portion 11R (the distance between the first upper surface 11U1 and the second upper surface 11U2). The difference between these distances becomes the thickness of the air layer 60. By adjusting the depth of the first concave portion 11R and the height of the second convex portion 21P, an air layer 60 with a desired thickness can be obtained.

[0046] The light-emitting device 100C shown in FIG. 7 includes a first portion 10C as shown in FIG. 3B, in which the second upper surface 11U2 of the first reflecting member 11 is located above the first upper surface 11U1. That is, the first portion 10C includes a first convex portion 11P. And, as shown in FIG. 4A, it includes a second portion 20B in which the second lower surface 21D2 of the second reflecting member 21 is located above the first lower surface 21D1. That is, the second portion 20B includes a second concave portion 21R. The height of the first convex portion 11P (the distance between the first upper surface 11U1 and the second upper surface 11U2) is greater than the depth of the second concave portion 21R (the distance between the first lower surface 21D1 and the second lower surface 21D2). The difference between these distances is the thickness of the air layer 60. By adjusting the depth of the second concave portion 21R and the height of the first convex portion 11P, an air layer 60 with a desired thickness can be obtained.

[0047] The light-emitting device 100D shown in FIG. 8 includes a first portion 10A as shown in FIG. 1B, in which the second upper surface 11U2 and the first upper surface 11U1 of the first reflecting member 11 are located on the same plane. And, as shown in FIG. 4B, it includes a second portion 20C in which the second lower surface 21D2 of the second reflecting member 21 is located below the first lower surface 21D1. That is, the second portion 20C includes a second convex portion 21P. The height of the second convex portion 21P (the distance between the first lower surface 21D1 and the second lower surface 21D2) is the thickness of the air layer 60. By adjusting the height of the second convex portion 21P, an air layer 60 with a desired thickness can be obtained.

[0048] The light-emitting device 100E shown in FIG. 9 includes a first portion 10C as shown in FIG. 3B, in which the second upper surface 11U2 of the first reflecting member 11 is located above the first upper surface 11U1. That is, the first portion 10C includes a first convex portion 11P. And, as shown in FIG. 1B, it includes a second portion 20A in which the second lower surface 21D2 and the first lower surface 21D1 of the second reflecting member 21 are located on the same plane. The height of the first convex portion 11P (the distance between the first upper surface 11U1 and the second upper surface 11U2) is the thickness of the air layer 60. By adjusting the height of the first convex portion 11P, an air layer 60 with a desired thickness can be obtained.

[0049] In addition to the above, the first portion 10C (FIG. 3B) and the second portion 20C (FIG. 4B) can be combined.

[0050] Hereinafter, in each embodiment, other components will be described in detail.

[0051] (Light-emitting element) The light-emitting device includes at least one light-emitting element 12. As the light-emitting element 12, for example, a semiconductor light-emitting element such as a light-emitting diode can be used. The light-emitting element 12 includes a semiconductor laminate 121 and a pair of positive and negative electrodes 122. The semiconductor laminate 121 includes, for example, an element substrate such as sapphire and a semiconductor layer formed thereon. Alternatively, the semiconductor laminate 121 can be composed of only a semiconductor layer without an element substrate. The planar shape of the light-emitting element 12 can be a polygon such as a triangle, a quadrilateral, or a hexagon. The size of the light-emitting element 12 can be, for example, 100 μm or more and 3000 μm or less on one side in a plan view. Specifically, it can be a square with one side of about 600 μm, about 1400 μm, about 1700 μm, etc. Also, the light-emitting element 12 may be a rectangle having a long side and a short side in a plan view. For example, it can have a size of 1100 μm × 200 μm.

[0052] The semiconductor laminate 121 includes an n-type semiconductor layer and a p-type semiconductor layer, and a light-emitting layer sandwiched therebetween. Such a semiconductor laminate including a light-emitting layer can include, for example, In x Al y Ga 1-x-y N (0 ≦ x, 0 ≦ y, x + y ≦ 1).

[0053] The semiconductor laminate 121 may have a structure including one or more light-emitting layers between an n-type semiconductor layer and a p-type semiconductor layer, or may have a structure in which a structure including an n-type semiconductor layer, a light-emitting layer, and a p-type semiconductor layer in this order is repeated a plurality of times. When the semiconductor laminate 121 includes a plurality of light-emitting layers, it may include light-emitting layers having different emission peak wavelengths, or may include light-emitting layers having the same emission peak wavelength. Note that the same emission peak wavelength includes cases where there is a variation of about several nm. The combination of emission peak wavelengths between the plurality of light-emitting layers can be appropriately selected. For example, when the semiconductor laminate includes two light-emitting layers, the light-emitting layers can be selected in combinations such as blue light and blue light, green light and green light, red light and red light, ultraviolet light and ultraviolet light, blue light and green light, blue light and red light, or green light and red light.

[0054] The light-emitting element 12 includes a pair of positive and negative electrodes 122 on the lower surface of the semiconductor laminate 121. As the electrode 122, an electrically conductive material can be used, and for example, it can be made of gold, silver, tin, platinum, rhodium, titanium, aluminum, tungsten, palladium, nickel, or an alloy thereof. The electrode 122 can include an ohmic electrode in contact with the lower surface of the semiconductor laminate 121 and a pad electrode connected to the ohmic electrode and connected to the outside. The thickness of the electrode can be, for example, 10 μm or more and 50 μm or less.

[0055] (Wavelength conversion member) The wavelength conversion member 13 includes a wavelength conversion material that absorbs light from the light-emitting element 12 and converts it into light of a different wavelength. The wavelength conversion member 13 is disposed directly on the upper surface of the light-emitting element 12 or indirectly via a light guide member 15 described later.

[0056] The planar shape of the wavelength conversion member 13 is a quadrangle. The thickness of the wavelength conversion member 13 can be appropriately selected according to the type and amount of the phosphor used, the target chromaticity, etc. The thickness of the wavelength conversion member 13 can be, for example, 20 μm to 200 μm.

[0057] The wavelength conversion member 13 can be formed by using a light-transmitting material such as resin, glass, or inorganic material as a binder and mixing and molding a phosphor as a wavelength conversion substance with the light-transmitting material. As the light-transmitting material, for example, resin materials such as epoxy resin, silicone resin, phenol resin, and polyimide resin, and inorganic materials such as glass and ceramics can be used. The light-transmitting material includes a base material such as a light-transmitting resin material, ceramics, or glass, and a phosphor as a wavelength conversion substance. As the base material, for example, thermosetting resins such as silicone resin, silicone-modified resin, epoxy resin, and phenol resin can be used. Also, thermoplastic resins such as polycarbonate resin, acrylic resin, methylpentene resin, and polynorbornene resin can be used. The light-transmitting material preferably has a transmittance of 70% or more, more preferably 80% or more, and even more preferably 90% or more with respect to the light from the light-emitting element.

[0058] As the phosphor, one that absorbs the light from the light-emitting element 12 and converts it into light of a different wavelength is used. In other words, one that can be excited by the light emission from the light-emitting element 12 is used. For example, as phosphors that can be excited by a blue light-emitting element or an ultraviolet light-emitting element, yttrium aluminum garnet-based phosphors (YAG:Ce) activated with cerium; lutetium aluminum garnet-based phosphors (LAG:Ce) activated with cerium; calcium nitrogen-containing aluminosilicate-based phosphors (CaO-Al2O3-SiO2) activated with europium and / or chromium; silicate-based phosphors ((Sr,Ba)2SiO4) activated with europium; nitride-based phosphors such as β-sialon phosphors, CASN-based phosphors, and SCASN-based phosphors; KSF-based phosphors (K2SiF6:Mn); sulfide-based phosphors, quantum dot phosphors, and the like can be mentioned. By combining these phosphors with a blue light-emitting element or an ultraviolet light-emitting element, light-emitting devices of various colors (for example, white light-emitting devices) can be manufactured. These phosphors can be used alone or in combination. When used in combination, they may be mixed or laminated. Also, the wavelength conversion member may contain various fillers and the like.

[0059] (First Reflective Member / Second Reflective Member / Third Reflective Member / Covering Member) The first reflective member 11, the second reflective member 21, the third reflective member 31, and the covering member 14 are all light-reflective members, and hereinafter they are collectively referred to as "reflective members". The reflective member is a member capable of reflecting light from the light-emitting element, and for example, a resin material or an inorganic material containing a light-reflective substance can be used. It is preferable that the reflectivity of the reflective member with respect to the light from the light-emitting element is 70% or more, more preferably 80% or more, and even more preferably 90% or more.

[0060] As the reflective member, for example, a resin material mainly composed of a thermosetting resin such as silicone resin, silicone-modified resin, epoxy resin, or phenolic resin can be used as the base material. As the light-reflective substance to be contained in the base material, for example, a white substance can be used. Specifically, for example, titanium oxide, silicon oxide, zirconium oxide, potassium titanate, aluminum oxide, aluminum nitride, boron nitride, mullite, etc. are suitable. The light-reflective substance can be in the form of particles, fibers, thin plate flakes, etc.

[0061] Also, as the reflective member, for example, it may be composed of a mixture of inorganic substances containing boron nitride and alkali metal silicate. This mixture can be produced by mixing a mixed powder of boron nitride powder and silicon oxide powder with an alkali solution (for example, potassium hydroxide) and then heat-curing. When the alkali solution is potassium hydroxide, when heat-curing is performed, silicon oxide reacts with potassium hydroxide to generate potassium silicate, which is an alkali metal silicate. Boron nitride is a member capable of reducing the shrinkage of the mixture during heat-curing. Note that aluminum oxide can be used instead of boron nitride.

[0062] When the third portion 30 includes the third reflective member 31 and the base 32, the above-described light-reflective substance can be disposed as a thin layer with a thickness on a part or all of the surface of the base 32 by a sputtering method, a vapor deposition method, or the like.

[0063] (Light-transmissive member) The light-transmissive member 22 is a portion that serves as the light extraction surface of the light-emitting device 100. As the light-transmissive member 22, for example, resin materials such as epoxy resin, silicone resin, phenol resin, and polyimide resin, and inorganic materials such as glass and ceramics can be used. The light-transmissive material 22 preferably has a transmittance of 70% or more with respect to the light from the light-emitting element 12, more preferably 80% or more, and even more preferably 90% or more. The light-transmissive member 22 can have a flat plate shape or a shape having a lens function. Examples of the shape having a lens function include a convex lens shape, a concave lens shape, and a Fresnel lens shape.

[0064] (Base) The base 32 is a member included in the third portion 30 and serves as a base for the third reflecting member 31. As the base 32, for example, resin materials such as epoxy resin, silicone resin, phenol resin, and polyimide resin, and inorganic materials such as glass and ceramics can be used.

[0065] (Joining member) The joining member 40 is a member that joins the first portion 10 and the second portion 20. Alternatively, the joining member 40 is a member that joins the first portion 10 and the third portion 30 and also joins the second portion 20 and the third portion 30. As the joining member 40, for example, resin materials such as epoxy resin, silicone resin, phenol resin, and polyimide resin can be used. The joining member 40 may contain titanium oxide, silicon oxide, zirconium oxide, potassium titanate, aluminum oxide, aluminum nitride, boron nitride, mullite, etc. in these resin materials. Further, the joining member preferably has a reflectance of 70% or more with respect to the light from the light-emitting element, more preferably 80% or more, and even more preferably 90% or more.

[0066] (Light guide member) The light guide member 15 is a member that joins the light-emitting element 12 and the wavelength conversion member 13. The light guide member 15 is disposed between the upper surface of the light-emitting element 12 and the lower surface of the wavelength conversion member 13. The light guide member 15 may further cover the side surface of the light-emitting element 12. As the light guide member 15, a translucent resin material can be used. For example, a resin material mainly composed of a thermosetting resin such as a silicone resin, a silicone-modified resin, an epoxy resin, or a phenolic resin is preferable. The light guide member 15 preferably has a transmittance of 70% or more, more preferably 80% or more, and even more preferably 90% or more with respect to the light from the light-emitting element. When the light-emitting element 12 and the wavelength conversion member 13 are joined by a direct bonding method, the light guide member 15 can be omitted.

[0067] (Substrate) The light-emitting device 100 can include a substrate 50. The substrate 50 is a plate-shaped member including a base material and a conductive wiring disposed on the base material. The first portion 10 is disposed on the upper surface of the substrate 50. Examples of the base material include insulating materials such as glass epoxy, resin, and ceramics, semiconductor materials such as silicon, and conductive materials such as copper. Among these, ceramics with high heat resistance and light resistance can be preferably used. Examples of the ceramics include aluminum oxide, aluminum nitride, silicon nitride, and LTCC. Further, a composite material of these insulating materials, semiconductor materials, and conductive materials can also be used. When a semiconductor material or a conductive material is used as the base material, the wiring can be disposed on the upper surface of the base material via an insulating layer. Examples of the material of the wiring include metals such as Fe, Cu, Ni, Al, Ag, Au, Pt, Ti, W, Pd, or alloys containing at least one of these.

[0068] This disclosure includes the following embodiments. [Item 1] A first portion including a light-emitting element, a wavelength conversion member disposed on the upper surface of the light-emitting element, and a first reflecting member covering the side surface of the light-emitting element and the side surface of the wavelength conversion member. A second portion including a light-transmitting member disposed via an air layer above the wavelength conversion member, and a second reflecting member disposed around the light-transmitting member. Comprising The upper surface of the first reflecting member has a first upper surface disposed around the wavelength conversion member and a second upper surface disposed around the first upper surface. The lower surface of the second reflecting member has a first lower surface disposed around the light-transmitting member and a second lower surface disposed around the first lower surface. The air layer is also disposed between the first upper surface of the first reflecting member and the first lower surface of the second reflecting member. The light-emitting device. [Item 2] The light-emitting device includes a third portion including a third reflecting member between the first portion and the second portion. The third portion is disposed between the second upper surface of the first reflecting member and the second lower surface of the second reflecting member. The air layer is in contact with the third reflecting member. The light-emitting device according to Item 1. [Item 3] The second upper surface of the first reflecting member is located above the first upper surface. The light-emitting device according to Item 1 or Item 2. [Item 4] The second upper surface of the first reflecting member is located below the first upper surface. The light-emitting device according to any one of Items 1 to 3. [Item 5] The second lower surface of the second reflecting member is located below the first lower surface. The light-emitting device according to any one of Items 1 to 4. [Item 6] The second lower surface of the second reflecting member is located above the first lower surface. The light-emitting device according to any one of Items 1 to 5. [Item 7] The second upper surface is disposed entirely around the outside of the first upper surface. The light-emitting device according to any one of Items 1 to 6. [Item 8] The second lower surface is disposed entirely around the outside of the first lower surface. The light-emitting device according to any one of Items 1 to 7. [Item 9] The second upper surface of the first reflecting member is located below the first upper surface. The light-emitting device according to claim 1 or 2, wherein the second lower surface of the second reflecting member is located below the first lower surface. [Claim 10] The second upper surface of the first reflecting member is located above the first upper surface. The light-emitting device according to claim 1 or 2, wherein the second lower surface of the second reflecting member is located above the first lower surface. [Claim 11] The second upper surface of the first reflecting member is located on the same plane as the first upper surface. The light-emitting device according to claim 1 or 2, wherein the second lower surface of the second reflecting member is located below the first lower surface. [Claim 12] The second upper surface of the first reflecting member is located above the first upper surface. The light-emitting device according to claim 1 or 2, wherein the second lower surface of the second reflecting member is located on the same plane as the first lower surface.

Description of Reference Numerals

[0069] 100... Light-emitting device 10 (10A, 10B, 10C)... First portion 11... First reflecting member (11U... Upper surface (11U1... First upper surface, 11U2... Second upper surface), 11D... Lower surface, 11S... Outer surface, 11P... First convex portion, 11M... First inner surface, 11R... First concave portion, ) 12... Light-emitting element (121... Semiconductor laminate, 122... Electrode) 13... Wavelength conversion member (13U... Upper surface) 14... Coating member 15... Light guide member 20 (20A, 20B, 20C)... Second portion 21... Second reflecting member (21U... Upper surface, 21D... Lower surface (21D1... First lower surface, 21D2... Second lower surface), 21S... Outer surface, 21P... Second convex portion, 21M... Second inner surface, 21R... Second concave portion) 22... Translucent member (22U... Upper surface, 22D... Lower surface) 30... Third portion 31…Third reflecting member (31U…upper surface, 31D…lower surface, 31S…outer surface, 31M…inner surface) 32…Base 40…Joining member 50…Substrate 60…Air layer

Claims

1. A first part including a light-emitting element, a wavelength conversion member disposed on an upper surface of the light-emitting element, and a first reflecting member covering a side surface of the light-emitting element and a side surface of the wavelength conversion member; A second part including a light-transmitting member disposed via an air layer above the wavelength conversion member and a second reflecting member disposed around the light-transmitting member; Comprising; An upper surface of the first reflecting member has a first upper surface disposed around the wavelength conversion member and a second upper surface disposed around the first upper surface; A lower surface of the second reflecting member has a first lower surface disposed around the light-transmitting member and a second lower surface disposed around the first lower surface; The air layer is also disposed between the first upper surface of the first reflecting member and the first lower surface of the second reflecting member, a light-emitting device.

2. The light-emitting device includes a third part including a third reflecting member between the first part and the second part, The third part is disposed between the second upper surface of the first reflecting member and the second lower surface of the second reflecting member, The air layer is in contact with the third reflecting member, the light-emitting device according to claim 1.

3. The second upper surface of the first reflecting member is located above the first upper surface, the light-emitting device according to claim 1 or claim 2.

4. The second upper surface of the first reflecting member is located below the first upper surface, the light-emitting device according to claim 1 or claim 2.

5. The second lower surface of the second reflecting member is located below the first lower surface, the light-emitting device according to claim 1 or claim 2.

6. The second lower surface of the second reflecting member is located above the first lower surface, the light-emitting device according to claim 1 or claim 2.

7. The second upper surface is disposed entirely around the outside of the first upper surface, the light-emitting device according to claim 1 or claim 2.

8. The second lower surface is disposed entirely around the outside of the first lower surface, the light-emitting device according to claim 1 or claim 2.

9. The second upper surface of the first reflecting member is located below the first upper surface, The second lower surface of the second reflecting member is located below the first lower surface, the light-emitting device according to claim 1 or claim 2.

10. The second upper surface of the first reflecting member is located above the first upper surface, The second lower surface of the second reflecting member is located above the first lower surface, the light-emitting device according to claim 1 or claim 2.

11. The second upper surface of the first reflecting member is located on the same plane as the first upper surface, The second lower surface of the second reflecting member is located below the first lower surface. The light-emitting device according to claim 1 or claim 2. **Claim 12** The second upper surface of the first reflecting member is located above the first upper surface, The second lower surface of the second reflecting member is located on the same plane as the first lower surface. The light-emitting device according to claim 1 or claim 2.

Images