Luminescent device

Abstract

To provide a luminescent device having high light extraction efficiency.SOLUTION: A luminescent device is provided including: a base substance having a recessed portion defined by a bottom portion and a wall portion positioned on the bottom portion; a light emitting element arranged in the recessed portion; and a light reflection member that is arranged consecutive to an upper surface of the bottom portion and an inner surface of the wall portion in the recessed portion of the base substance, wherein, in a cross-sectional view, the inner surface of the wall portion includes: a first surface that is consecutive to the upper surface of the bottom portion; a second surface that is disposed at a position higher than the first surface; and a third surface that connects an upper end of the first surface and a lower end of the second surface to each other, wherein the shortest distance between the second surface and the light emitting element is larger than that between the first surface and the light emitting element, and the third surface is disposed at a position below the upper surface of the light emitting element, and the upper end of the light reflection member is disposed at a position below the upper surface of the wall portion.SELECTED DRAWING: Figure 1

Description

[Technical field]

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

[0002] Known light-emitting devices include a light-emitting device having a light-emitting element such as an LED inside a base having a recess, and a light-reflective member that reflects the light of the light-emitting element. For example, Patent Document 1 discloses a semiconductor light-emitting device having a molded body having a recess, a semiconductor light-emitting element mounted in the recess, and a highly reflective resin layer provided so as to cover the bottom and side surfaces of the recess of the molded body. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2008-060344 A Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the present disclosure is to provide a light emitting device having high light extraction efficiency. [Means for solving the problem]

[0005] The light emitting device of the present disclosure includes a base having a recess defined by a bottom and a wall located on the bottom, a light emitting element arranged in the recess, and a light reflective member arranged contiguous with an upper surface of the bottom and an inner surface of the wall within the recess of the base, wherein in a cross-sectional view, the inner surface of the wall has a first surface continuing from an upper surface of the bottom, a second surface located higher than the first surface, and a third surface connecting an upper end of the first surface and a lower end of the second surface, wherein the shortest distance between the second surface and the light emitting element is greater than the shortest distance between the first surface and the light emitting element, the third surface is located at the same height as the upper surface of the light emitting element or lower than the upper surface of the light emitting element, and the upper end of the light reflective member is located lower than the upper surface of the wall. Effect of the Invention

[0006] The present disclosure can provide a light emitting device having high light extraction efficiency. [Brief description of the drawings]

[0007] [Figure 1] 1 is a schematic end view of a light emitting device 100 according to a first embodiment. [Diagram 2] 2 is a schematic top view of the light emitting device 100 according to the first embodiment shown in FIG. [Diagram 3] 2 is a schematic cross-sectional view of a base material 13 of the light emitting device 100 according to the first embodiment shown in FIG. [Figure 4] 2 is a schematic top view of the base 10 of the light emitting device 100 according to the first embodiment shown in FIG. [Diagram 5] FIG. 11 is a schematic end view of a light emitting device 101 according to a second embodiment. [Figure 6] 6 is a schematic top view of the light emitting device 101 according to the second embodiment shown in FIG. [Figure 7] 7 is a schematic cross-sectional view of the light emitting device 101 according to the second embodiment taken along line VII-VII. [Figure 8] 8 is a schematic cross-sectional view of a light emitting device 101 according to a second embodiment taken along line VIII-VIII. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, with reference to the drawings, an embodiment for carrying out the invention according to the present disclosure will be described. Note that the light emitting device described below is for embodying the technical idea of ​​the invention according to the present disclosure, and unless otherwise specified, the invention according to the present disclosure is not limited to the following. In each drawing, the same reference numerals may be attached to members having the same functions. In consideration of the explanation or ease of understanding of the main points, the embodiments may be shown separately for convenience, but partial replacement or combination of the configurations shown in different embodiments is possible. In the embodiments described below, the description of matters common to the above will be omitted, and only the differences will be described. In particular, the same action and effect due to the same configuration will not be mentioned in each embodiment one by one. The size and positional relationship of the members shown in each drawing may be exaggerated in order to clarify the explanation. In addition, an end view showing only the cut surface may be used as a cross-sectional view.

[0009] <Embodiment 1> A light emitting device 100 according to a first embodiment of the present disclosure will be described with reference to Figs. 1 and 2. Fig. 1 is a schematic end view of the light emitting device 100. Fig. 2 is a schematic top view of the light emitting device 100. Note that the light-transmitting member is omitted in Fig. 2. The schematic end view shown in Fig. 1 shows the light emitting device 100 cut along line II shown in Fig. 2. In Fig. 2, line II passes through the centers of two opposing side surfaces 10x, 10y of the base 10. Note that in the light emitting device of the present disclosure, the bottom side of the base is defined as the bottom, and the top side of the light-transmitting member is defined as the top. That is, the upper side of Fig. 1 is defined as the top, and the lower side is defined as the bottom.

[0010] 1 and 2, a light emitting device 100 according to a first embodiment of the present disclosure includes a base 10 having a recess 14 defined by a bottom 11 and a wall 12 located on the bottom 11, a light emitting element 20 disposed in the recess 14, and a light reflective member 30 disposed in continuity with an upper surface 15 of the bottom 11 and an inner surface 16 of the wall 12 in the recess 14 of the base 10. In a cross-sectional view, the inner surface 16 of the wall 12 has a first surface 41 continuing from the upper surface 15 of the bottom 11, a second surface 42 located above the first surface 41, and a third surface 43 connecting an upper end of the first surface 41 and a lower end of the second surface 42. The shortest distance d2 between the second surface 42 and the light-emitting element 20 is greater than the shortest distance d1 between the first surface 41 and the light-emitting element 20, the third surface 43 is located at the same height as the upper surface 24 of the light-emitting element 20 or lower than the upper surface 24 of the light-emitting element 20, and the upper end 30a of the light-reflective member 30 is located lower than the upper surface 12a of the wall portion 12.

[0011] The light emitting device 100 according to the first embodiment of the present disclosure includes a light-transmitting member 50 disposed on the upper surface 12a of the base 10 with a bonding member 51 interposed therebetween.

[0012] In the light emitting device described in Patent Document 1, the upper end of the resin layer disposed in the recess of the molded body is located at approximately the same height as the upper surface of the molded body. In addition, the light emitting device described in Patent Document 1 has a step on the side surface of the recess of the molded body, and the upper surface of the light emitting element is located at a lower position than the step on the side surface of the recess. Therefore, in the light emitting device described in Patent Document 1, more of the light emitted from the light emitting element hits the step and the resin layer disposed above the step. As a result, the proportion of the light emitted from the light emitting device that is not reflected by the resin layer and is directly emitted to the outside of the light emitting device is relatively low. On the other hand, in the light emitting device of the present disclosure, the upper end 30a of the light reflective member 30 is located below the upper surface 12a of the wall portion 12, and the third surface 43 of the wall portion is located at the same height as the upper surface 24 of the light emitting element 20 or below the upper surface 24 of the light emitting element 20, so that the proportion of the light emitted from the light emitting element 20 that is not reflected by the light reflective member 30 and is directly emitted to the outside of the light emitting device is high. This can improve the light extraction efficiency of the light emitting device.

[0013] (base) The base 10 has a bottom 11 and a wall 12 located on the bottom 11. The bottom 11 and the wall 12 define a recess 14. The base 10 may also include a wiring layer 17 disposed on an upper surface 15 of the bottom 11 in the recess 14, and an external electrode 19 disposed on a lower surface 18 of the bottom 11.

[0014] As shown in FIG. 2, the shape of the outer edge of the wall portion 12 of the base 10 is substantially rectangular when viewed from above. Each corner of the rectangle is removed in an arc shape. The corners may be right-angled or rounded. Furthermore, the shape of the inner edge of the third surface 43 and the shape of the outer edge of the third surface 43 are substantially rectangular when viewed from above. Each corner of the rectangle is rounded. The corners of the inner edge and outer edge of the third surface 43 may be right-angled.

[0015] In the light-emitting device of the present disclosure, the shape of the outer edge of the wall of the base is not limited to the above-mentioned substantially rectangular shape, and may be any known shape, such as a circle, etc. The shapes of the inner edge and outer edge of the third surface are also not limited to the above-mentioned substantially rectangular shape, and may be shapes that follow the shape of the outer edge of the wall of the base, for example.

[0016] In a cross-sectional view, the inner surface 16 of the wall portion 12 has a first surface 41 continuing from the upper surface 15 of the bottom portion 11, a second surface 42 located above the first surface 41, and a third surface 43 connecting the upper end of the first surface 41 and the lower end of the second surface 42. The shortest distance d2 between the second surface 42 and the light-emitting element 20 is greater than the shortest distance d1 between the first surface 41 and the light-emitting element 20. The first surface 41, the second surface 42, and the third surface 43 are connected as described above, thereby forming a step on the inner surface 16 of the wall portion 12. By providing a step on the inner surface 16 of the wall portion 12, it is possible to suppress the light-reflective member from creeping up during the manufacture of the light-emitting device, particularly creeping up to the upper surface 12a of the wall portion 12.

[0017] The first surface 41 may be disposed approximately perpendicular to the upper surface 15 of the bottom portion 11. Similarly, the second surface 42 may be disposed approximately perpendicular to the upper surface 15 of the bottom portion 11. In this specification, approximately perpendicular is not limited to an angle of exactly 90°, and may also include an angle in the range of about 90°±3°.

[0018] The upper end of the first surface 41 and the lower end of the second surface 42 are located at substantially the same height as the upper surface 15 of the bottom portion 11. That is, the third surface 43 connecting the upper end of the first surface 41 and the lower end of the second surface 42 can be disposed approximately parallel to the upper surface 15 of the bottom portion 11. In this specification, approximately parallel is not limited to being strictly parallel, and can also include cases where the deviation from parallelism is within a range of about ±3°.

[0019] In the light emitting device 100 of the first embodiment, the upper end of the second surface 42 coincides with the inner peripheral edge of the upper surface 12a of the wall portion.

[0020] In a cross-sectional view, the shortest distance d2 between the second surface 42 and the light-emitting element 20 is greater than the shortest distance d1 between the first surface 41 and the light-emitting element 20. In other words, in a cross-sectional view, the second surface 42 is located outside the base 10 relative to the first surface 41. Typically, the difference between the shortest distance d2 and the shortest distance d1 (i.e., the shortest distance d2−the shortest distance d1) is the same as the width of the third surface 43.

[0021] The shortest distance d1 between the first surface 41 and the light emitting element 20 is not particularly limited. The shortest distance d1 between the first surface 41 and the light emitting element 20 may be, for example, 0.2 mm or more, preferably 0.3 mm or more. By setting the shortest distance d1 in this range, the space between the first surface 41 and the light emitting element 20 is widened, and the degree of freedom in arranging the light reflective member 30 is improved. As a result, the space between the light reflective member 30 and the side surface of the light emitting element 20 is widened, and the light emitted from the side surface of the light emitting element 20 is easily extracted to the outside of the light emitting device 100 without being reflected by the light reflective member 30 and entering the light emitting element 20 again, so that the light extraction efficiency of the light emitting device 100 can be further improved. In addition, the shortest distance d1 may be, for example, 2.0 mm or less, preferably 1.0 mm or less. By setting the shortest distance d1 in this range, it is easy to miniaturize the light emitting device 100. In one embodiment, the shortest distance d1 may be 0.2 mm or more and 2.0 mm or less, preferably 0.3 mm or more and 1.0 mm or less, for example, 0.6 mm or more and 0.8 mm or less.

[0022] The ratio (h0 / d1) of the distance h0 between the upper surface 12a of the wall portion of the base and the upper surface 15 of the bottom portion 11 to the shortest distance d1 between the first surface 41 and the light emitting element 20 can be preferably 0.5 or more, more preferably 1.0 or more, and even more preferably 1.2 or more. By setting the ratio of the distance h0 to the shortest distance d1 in the above range, the distance between the inner surface of the wall portion and the light emitting element becomes closer, and the light emitting device can be easily miniaturized. In addition, the ratio (h0 / d1) of the distance h0 to the shortest distance d1 can be preferably 10.0 or less, more preferably 6.0 or less, and even more preferably 3.0 or less. By setting the ratio of the distance h0 to the shortest distance d1 in such a range, the light emitted from the side surface of the light emitting element 20 is easily extracted directly to the outside of the light emitting device 100 without being reflected by the light reflective member 30 arranged on the first surface 41, and therefore the light extraction efficiency of the light emitting device 100 can be further improved. In one embodiment, the ratio of the distance h0 to the shortest distance d1 (h0 / d1) can be 0.5 or more and 10.0 or less, preferably 1.0 or more and 6.0 or less, and more preferably 1.2 or more and 3.0 or less.

[0023] The width w1 of the third surface 43 in the cross-sectional view is not particularly limited. The width w1 of the third surface 43 in the cross-sectional view may be, for example, 0.01 mm or more, preferably 0.02 mm or more. By setting the width w1 of the third surface 43 within the above range, it is possible to further suppress the light reflective member 30 from creeping up onto the upper surface 12a of the wall portion 12 during manufacturing. In addition, the width w1 of the third surface 43 may be, for example, 0.5 mm or less, preferably 0.1 mm or less. By setting the width w1 of the third surface 43 within the above range, it is possible to increase the proportion of the space in the recess in the light emitting device 100, thereby improving the degree of freedom in the arrangement of the light reflective member 30. As a result, it is possible to secure a wide space between the light reflective member 30 and the side surface of the light emitting element 20, so that the light emitted from the side surface of the light emitting element 20 can be easily taken out to the outside of the light emitting device 100 without being reflected by the light reflective member 30 and re-entering the light emitting element 20. In one embodiment, the width w1 of the third surface 43 may be 0.01 mm or more and 0.5 mm or less, preferably 0.02 mm or more and 0.1 mm or less.

[0024] The shortest distance d2 between the second surface 42 and the light-emitting element 20 can be the shortest distance d1 plus the width w1.

[0025] In a cross-sectional view, the third surface 43 of the wall portion 12 is located at the same height as the upper surface 24 of the light-emitting element 20 or lower than the upper surface 24 of the light-emitting element 20. In other words, the distance h1 between the upper end of the first surface 41 and the upper surface 15 of the bottom portion 11 is the same as the distance h10 between the upper surface 24 of the light-emitting element 20 and the upper surface 15 of the bottom portion 11, or is smaller than the distance h10 between the upper surface 24 of the light-emitting element 20 and the upper surface 15 of the bottom portion 11. Preferably, the third surface 43 of the wall portion 12 is located lower than the upper surface 24 of the light-emitting element 20. By arranging the third surface 43 of the wall portion 12 at the same height as the upper surface 24 of the light-emitting element 20 or lower than the upper surface 24 of the light-emitting element 20, the light emitted from the light-emitting element 20 and directed upward from the wall portion 12 is easily emitted directly from the light-emitting device 100 without being reflected by the light-reflective member 30. That is, a wide linear optical path is ensured between the side surface of the light-emitting layer of the light-emitting element 20 and the inner edge of the upper surface 12a of the wall portion 12. Therefore, the proportion of light emitted from the light-emitting element 20 that is directly emitted upward from the light-emitting device 100 without being reflected by the light-reflective member 30 increases, and the light extraction efficiency of the light-emitting device 100 can be improved.

[0026] In a cross-sectional view, the difference between the distance h10 between the upper surface 24 of the light-emitting element 20 and the upper surface 15 of the bottom 11 and the distance h1 between the upper end of the first surface 41 and the upper surface 15 of the bottom 11 is not particularly limited. The difference between the distance h10 between the upper surface 24 of the light-emitting element 20 and the upper surface 15 of the bottom 11 and the distance h1 between the upper end of the first surface 41 and the upper surface 15 of the bottom 11 may be, for example, 0.01 mm or more, preferably 0.02 mm or more. By setting the difference between the distance h10 and the distance h1 within such a range, the light extraction efficiency of the light-emitting device 100 can be further increased. In addition, the difference between the distance h10 and the distance h1 may be, for example, 1.0 mm or less, preferably 0.5 mm or less. In one embodiment, the difference between the distance h10 and the distance h1 may be 0.01 mm or more and 1.0 mm or less, preferably 0.02 mm or more and 0.5 mm or less.

[0027] In a cross-sectional view, the distance h1 between the upper end of the first surface 41 and the upper surface 15 of the bottom portion 11 may be greater than the distance h2 between the upper end of the second surface 42 and the third surface 43. By making the distance h1 greater than the distance h2, the proportion of h1 in the inner surface 16 of the wall portion increases, and the position of the third surface 43 becomes higher. The third surface 43 suppresses the light reflective member 30 from creeping up to the upper surface 12a of the wall portion 12 during the manufacture of the light emitting device 100, so that the light reflective member 30 is typically formed up to the vicinity of the inner edge of the third surface 43. Therefore, in the case of having the third surface 43 as in the light emitting device 100 of the present disclosure, the higher the third surface 43 is located, the easier it is to arrange the light reflective member 30 to a higher position.

[0028] In a cross-sectional view, the ratio (h1 / h2) of the distance h1 between the upper end of the first surface 41 and the upper surface 15 of the bottom portion 11 to the distance h2 between the upper end of the second surface 42 and the third surface 43 may be preferably 1.01 or more, more preferably 1.5 or more, and even more preferably 3.0 or more. By setting the ratio of the distance h1 to the distance h2 in this range, it becomes easy to form the light reflective member 30 to a higher position. In addition, the ratio (h1 / h2) of the distance h1 to the distance h2 may be preferably 16.0 or less, more preferably 8.0 or less, and even more preferably 4.0 or less. By setting the ratio of the distance h1 to the distance h2 in this range, the distance between the third surface 43 and the upper surface 12a of the wall portion becomes large, and the light reflective member 30 can be more effectively prevented from creeping up to the upper surface 12a of the wall portion. In one embodiment, the ratio of the distance h1 to the distance h2 (h1 / h2) can be 1.01 or more and 16.0 or less, preferably 1.5 or more and 8.0 or less, and more preferably 3.0 or more and 4.0 or less.

[0029] The base material 13 of the substrate 10 can be formed of a single material such as an insulating material, such as glass, ceramics, resin, wood, or pulp, or a conductive material, such as a semiconductor or metal (e.g., copper, silver, gold, aluminum, etc.), or a composite material thereof. The material of the base material 13 is preferably a metal, ceramics, etc., and more preferably an inorganic material, such as ceramics. Examples of the ceramics include aluminum oxide, aluminum nitride, silicon nitride, and mullite. The ceramics are preferably aluminum nitride, which has high heat dissipation properties. The bottom 11 and wall 12 of the base material 13 may be made of the same material, or may be made of different materials.

[0030] As shown in FIG. 3, the base material 13 may have a laminated structure. For example, the base material 13 may be a laminate of a first layer 10a, a second layer 10b, and a third layer 10c. In this embodiment, the first layer 10a may form the bottom portion 11, and the second layer 10b and the third layer 10c may form the wall portion 12. A part of the second layer 10b forms the first surface 41 and the third surface 43. A part of the third layer 10c forms the second surface 42 and the upper surface 12a of the wall portion. Each layer may further have a laminated structure composed of multiple layers.

[0031] The base 10 includes a wiring layer 17 and an external electrode 19. As shown in FIG. 4, the wiring layer 17 is disposed on the upper surface 15 of the bottom 11 and is electrically connected to an electrode 23 of the light-emitting element 20 described later. The dashed line in FIG. 4 indicates the outer edge of the light-emitting element 20 when the light-emitting element 20 is disposed. The wiring layer 17 can have a function of blocking the light-reflective member 30 on the upper surface 15 of the bottom 11 by a step due to its thickness. For example, in the example shown in FIG. 4, the wiring layer 17 has an outer edge 17b located between the outer edge of the light-emitting element 20 and the first surface 41 of the wall portion, and on the upper surface 15 of the bottom 11, the wiring layer 17 can suppress the light-reflective member 30 from flowing from the first surface 41 side to the light-emitting element 20 side by the step of the outer edge 17b. The external electrode 19 is disposed on the lower surface 18 of the bottom 11. The bottom 11 has a through hole, and the wiring layer 17 and the external electrode 19 are electrically connected by an internal wiring disposed in the through hole. The light emitting device 100 is electrically connected to the outside by the external electrode 19.

[0032] (Light emitting element) The light emitting element 20 is disposed on the bottom 11 of the base 10 within the recess 14. The light emitting element 20 is preferably disposed at the center of the bottom 11 of the base 10. Note that in the light emitting device of the present disclosure, a plurality of light emitting elements may be disposed on the bottom 11 of the base 10.

[0033] The shape of the light-emitting element 20 in the top view shown in Fig. 2 is rectangular. Note that in the light-emitting device of the present disclosure, the shape of the light-emitting element 20 in the top view may be any shape. The shape of the light-emitting element 20 in the top view may be, for example, a polygon such as a triangle or a hexagon.

[0034] In top view, two opposing sides of the rectangular outer edge of the light emitting element 20 are parallel to two opposing sides of the rectangular outer edge of the base 10. In addition, other two opposing sides of the outer edge of the light emitting element 20 are parallel to other two opposing sides of the outer edge of the base 10. Note that the outer edges of the light emitting element 20 and the base 10 may be rectangular, and the outer edge of the light emitting element 20 may be rotated 45 degrees with respect to a central axis passing through the center of the bottom 11 of the base 10 from a state in which two opposing sides of the outer edge of the light emitting element 20 are parallel to two sides of the outer edge of the base 10 in top view.

[0035] The light-emitting element 20 includes a substrate 21 and a semiconductor layer 22. The substrate 21 can be a crystal growth substrate capable of growing a semiconductor crystal that constitutes the semiconductor layer 22. The substrate 21 is, for example, a sapphire substrate or a gallium nitride substrate. The semiconductor layer 22 includes, for example, an n-type semiconductor layer, a p-type semiconductor layer, and a light-emitting layer disposed between the n-type semiconductor layer and the p-type semiconductor layer.

[0036] 1, in the light emitting device 100 of the first embodiment, two electrodes 23 are disposed on the lower surface of the semiconductor layer 22, and are each electrically connected to the wiring layer 17. The two electrodes 23 disposed on the lower surface of the semiconductor layer 22 are a so-called p-electrode and n-electrode. The p-electrode is electrically connected to the p-type semiconductor layer. The n-electrode is electrically connected to the n-type semiconductor layer.

[0037] The semiconductor layer 22 may be a double heterojunction. The light emitting layer may have a structure such as a single quantum well (SQW) or may have a structure having a plurality of well layers such as a multiple quantum well (MQW). The semiconductor layer 22 is configured to be capable of emitting visible light or ultraviolet light. The semiconductor layer 22 including such a light emitting layer may be, for example, In x Al y Ga 1-x-y N, where 0≦x, 0≦y, x+y≦1. The peak wavelength of the light emitted from the semiconductor layer 22 is, for example, in the range of 250 nm to 630 nm.

[0038] (Light-reflecting member) The light reflective member 30 reflects the light emitted from the light emitting element 20. The light reflected by the light reflective member 30 is extracted from the light emitting device 100 in the upward direction of the base 10.

[0039] The light reflective member 30 is disposed along the inner surface 16 of the wall portion 12 of the base 10, continuously on the upper surface 15 of the bottom portion 11 of the base 10 and on the inner surface 16 of the wall portion.

[0040] As shown in FIG. 1, in the light-emitting device 100 of embodiment 1, the light-reflective member 30 is continuously disposed on a portion of the upper surface 15 of the bottom 11, the entire surface of the first surface 41, the entire surface of the third surface 43, and a portion of the second surface 42, and is disposed so as not to contact the upper end of the second surface 42.

[0041] In the light emitting device of the present disclosure, the arrangement of the light reflective member 30 is not limited to the example shown in Fig. 1. For example, the light reflective member 30 may be arranged continuously on a part of the upper surface 15 of the bottom 11, the entire surface of the first surface 41, and a part of the third surface 43, and may not be arranged on the second surface 42. In addition, the light reflective member 30 may be arranged continuously on a part of the upper surface 15 of the bottom 11 and the first surface 41, and may not be arranged on the second surface 42 and the third surface 43.

[0042] The area of ​​the upper surface 15 of the bottom 11 in which the light-reflective member 30 is disposed may be an area extending from the connection between the upper surface 15 of the bottom 11 and the first surface 41 toward the center of the upper surface 15 of the bottom 11, which area is 0.1 mm or more and 1.8 mm or less, preferably 0.3 mm or more and 1.0 mm or less.

[0043] The distance between the upper end of the second surface 42 and the upper end 30a of the light reflective member 30 may be preferably 0.05 mm or more, more preferably 0.1 mm or more, and even more preferably 0.15 mm or more. By setting the distance between the upper end of the second surface 42 and the upper end 30a of the light reflective member 30 in this range, the light emitted directly to the outside of the light emitting device without being reflected by the light reflective member 30 increases among the light from the light emitting element 20 toward the upper side of the wall portion 12, and the light extraction efficiency of the light emitting device is improved. The distance between the upper end of the second surface 42 and the upper end 30a of the light reflective member 30 may be preferably 0.5 mm or less, more preferably 0.4 mm or less, and even more preferably 0.3 mm or less. By setting the distance between the upper end of the second surface 42 and the upper end 30a of the light reflective member in this range, a wider range of the inner surface 16 of the wall portion can be covered by the light reflective member 30, and the light extraction efficiency of the light emitting device is improved.

[0044] 2, in top view, light reflective member 30 can be continuously disposed so as to surround the periphery of light emitting element 20. By disposing light reflective member 30 so as to surround the periphery of light emitting element 20, more of the light emitted from light emitting element 20 can be reflected, improving the light extraction efficiency of the light emitting device.

[0045] In top view, light reflective member 30 can be preferably disposed at a distance from light emitting element 20. In top view, the shortest distance between light reflective member 30 and light emitting element 20 can be preferably 0.1 mm or more and 1.5 mm or less, preferably 0.2 mm or more and 1.0 mm or less.

[0046] The shortest distance between the surface of the light reflective member 30 and the light emitting element 20 may increase from below the wall 12 of the base 10 toward above the wall 12 .

[0047] In a cross-sectional view, the surface of light reflective member 30 may have a concave curved surface recessed toward the outer edge side of base 10. By making the surface of light reflective member 30 a concave curved surface, light emitted from light emitting element 20 can be more efficiently reflected upward.

[0048] In the light-emitting device of the present disclosure, the surface of the light-reflective member is not limited to having a concave curved surface. For example, in a cross-sectional view, the surface of the light-reflective member 30 may have a convex curved surface that bulges toward the light-emitting element 20. In addition, in a cross-sectional view, the surface of the light-reflective member 30 may be linear. In the light-reflective member 30 having a linear surface, the distance between the surface and the light-emitting element 20 increases at a constant rate from below the wall portion 12 to above the wall portion 12.

[0049] In a cross-sectional view, light reflective member 30 is located below a straight line connecting a lower end P1 of the side surface of semiconductor layer 22 of light emitting element 20 facing inner surface 16 of wall portion 12 and an upper end P2 of inner surface 16 of wall portion 12. By disposing light reflective member 30 below the straight line connecting P1 and P2, the proportion of light that is directly emitted to the outside of the light emitting device out of the light emitted from light emitting element 20 increases, and the light extraction efficiency of the light emitting device increases.

[0050] There are no particular limitations on the light reflective member 30 as long as it has a higher reflectance for the light emitted from the light emitting element 20 than the base material 13 of the substrate 10 .

[0051] The light reflective member 30 may be, for example, a member in which a light diffusing material is contained in a resin, or a member containing a plurality of inorganic materials.

[0052] In the member in which the resin contains a light diffusing material, the resin may be, for example, a silicone resin, an epoxy resin, an acrylic resin, etc. The light diffusing material may be, for example, titanium oxide, silicon oxide, aluminum oxide, zinc oxide, etc.

[0053] The member in which a plurality of inorganic materials are mixed includes a light reflecting material and a support member that supports the light reflecting material.

[0054] The light reflector can be, for example, boron nitride or aluminum oxide, which can reflect light from ultraviolet light to visible light.

[0055] The light reflecting material may be a primary particle, or may be a secondary particle formed by agglomeration of two or more primary particles. The light reflecting material may also contain primary particles and secondary particles.

[0056] The particles of the light reflecting material may preferably be plate-shaped particles.

[0057] The average particle size of the light reflector may be preferably 0.6 μm or more and 43 μm or less. When the light reflector is boron nitride, the average particle size of the light reflector is, for example, 6 μm or more and 43 μm or less. When the light reflector is aluminum oxide, the average particle size of the light reflector is, for example, 0.6 μm or more and 10 μm or less.

[0058] The average particle size of the light reflecting material is calculated using a scanning electron microscope "TM3030Plus" manufactured by Hitachi High-Technologies Corporation. First, one side of a carbon double-sided tape is attached to the sample stage of the microscope, and then a light reflecting material is placed on the other side of the double-sided tape. The number of pixels of the microscope is set to 1.23 million pixels, the magnification is set to 1000 to 2000 times, and images of 100 light reflecting material particles are obtained. Then, the particle size of each particle is measured using image analysis software. In this specification, the particle size of the light reflecting material is the maximum diameter among the diameters when viewed from one main surface of the light reflecting material. Next, the median diameter of the measured particles is calculated, and the calculated value is the average particle size of the light reflecting material. The particle size of the light reflecting material may also be calculated by extracting a cross section of the light reflective member using a SEM and measuring it using image analysis software.

[0059] The support member may preferably include silica and an alkali metal.

[0060] The content ratio of silica to light reflecting material contained in light reflecting member 30 is, for example, 1:4 to 1:1 in mass ratio. That is, the mass of the light reflecting material contained in light reflecting member 30 is, for example, 1 to 4 times the mass of silica contained in light reflecting member 30. By setting the content ratio of silica to light reflecting material to 1:4 to 1:1, it is possible to reduce shrinkage while maintaining the hardening properties during production.

[0061] The alkali metal contained in the light reflective member 30 may be, for example, one or both of potassium and sodium.

[0062] Preferably, the light reflective member 30 may further include a scattering material. When the light reflective member 30 includes a scattering material, the light reflectance of the light reflective member 30 is improved.

[0063] The scattering material contained in the light reflective member 30 may be, for example, a scattering material containing zirconium oxide or titanium oxide. The scattering material in the light reflective member 30 is present in a dispersed state in the silica of the support member.

[0064] When the light emitting element 20 emits ultraviolet light, the scattering material may preferably contain zirconium oxide, which has little light absorption in the ultraviolet wavelength region. The zirconium oxide contained in the scattering material may be simple zirconium oxide, or may be zirconium oxide coated with a coating film composed of one or more of silica, aluminum oxide, zinc, organic materials, etc. The zirconium oxide contained in the scattering material may be stabilized zirconium oxide to which calcium, magnesium, yttrium, aluminum, etc. have been added, or partially stabilized zirconium oxide.

[0065] The titanium oxide contained in the scattering material may be titanium oxide alone, or the surface of titanium oxide may be coated with a coating film composed of one or more of silica, aluminum oxide, zirconium oxide, zinc, organic materials, etc.

[0066] The average particle size of the scattering material is desirably smaller than that of the light reflecting material. By making the average particle size of the scattering material smaller than that of the light reflecting material, the scattering material is easily arranged in the gaps between the light reflecting materials, so that it is possible to suppress the light emitted from the light emitting element 20 from passing through the gaps between the light reflecting materials and passing through the light reflective member 30. The average particle size of the scattering material is measured by a laser diffraction method.

[0067] (Translucent member) The light emitting device 100 of the first embodiment includes a light-transmitting member 50 disposed on a base 10. The light-transmitting member 50 is connected to the top of the base 10 by a joining member 51. The light-transmitting member 50 is disposed apart from the light-reflective member 30. Note that the light-transmitting member 50 is not an essential element in the light emitting device of the present disclosure, and may not be included.

[0068] The light-transmitting member 50 is a member that transmits the light emitted from the light-emitting element 20, and can be a member that transmits preferably 60% or more, more preferably 70% or more of the light emitted from the light-emitting element 20.

[0069] The light-transmitting member 50 is a light-transmitting member including a light-transmitting resin material, an inorganic material, etc. Examples of the resin material include thermosetting resins such as silicone resin, silicone modified resin, epoxy resin, and phenol resin, and thermoplastic resins such as polycarbonate resin, acrylic resin, methylpentene resin, and polynorbornene resin. Examples of the inorganic material include glass, sapphire, etc.

[0070] The light-transmitting member 50 may contain a phosphor.

[0071] The phosphor may be an yttrium-aluminum-garnet phosphor (e.g., Y3(Al,Ga)5O 12 :Ce), lutetium aluminum garnet phosphors (e.g., Lu3(Al,Ga)5O 12 :Ce), terbium aluminum garnet phosphors (e.g., Tb3(Al,Ga)5O 12 :Ce), CCA phosphors (e.g., Ca10 (PO4)6Cl2:Eu), SAE phosphors (e.g., Sr4Al 14 O 25 :Eu), chlorosilicate phosphors (e.g., Ca8MgSi4O 16 Cl2:Eu), β-sialon phosphors (e.g., (Si,Al)3(O,N)4:Eu), α-sialon phosphors (e.g., Ca(Si,Al) 12 (O,N) 16 :Eu), SLA phosphors (e.g., SrLiAl3N4:Eu), CASN phosphors (e.g., CaAlSiN3:Eu) or SCASN phosphors (e.g., (Sr,Ca)AlSiN3:Eu), nitride phosphors such as KSF phosphors (e.g., K2SiF6:Mn), KSAF phosphors (e.g., K2Si 0.99 Al 0.01 F 5.99 Examples of the phosphor that can be used include fluoride phosphors such as 3.5MgO·0.5MgF2·GeO2:Mn) or MGF phosphors (e.g., 3.5MgO·0.5MgF2·GeO2:Mn), phosphors having a perovskite structure (e.g., CsPb(F,Cl,Br,I)3), and quantum dot phosphors (e.g., CdSe, InP, AgInS2, or AgInSe2). The phosphor to be added to the light-transmitting member 50 may be one type of phosphor or multiple types of phosphors.

[0072] The bonding member 51 may be, for example, solder (eg, Au-Sn, Au-In), low melting point glass, or an adhesive such as resin (eg, silicone resin, epoxy resin).

[0073] (Sealing member) In the light emitting device, a sealing member for sealing the light emitting element 20 may be disposed in the recess 14 of the base 10. For example, a silicone resin or the like may be used as a base material for the sealing member. The sealing member may contain a phosphor. The sealing member disposed in the recess 14 may seal members disposed on the bottom 11 of the base 10, such as the light reflective member 30 and the wiring layer 17.

[0074] <Embodiment 2> A light emitting device 101 according to a second embodiment of the present disclosure will be described with reference to Figs. 5 and 6. Fig. 5 is a schematic end view of the light emitting device 101. Fig. 6 is a schematic top view of the light emitting device 101. The schematic end view shown in Fig. 5 shows the light emitting device 101 cut in the height direction along line VV shown in Fig. 6. In Fig. 6, line VV passes through the centers of two opposing side surfaces 10x, 10y of the base 10.

[0075] As shown in Figures 5 and 6, the light-emitting device 101 of embodiment 2 of the present disclosure mainly differs from the light-emitting device 100 of embodiment 1 above in that it has a fourth surface 44 located above the second surface 42, and a fifth surface 45 connecting the upper end of the second surface 42 and the lower end of the fourth surface 44, and the shortest distance d5 between the fourth surface 44 and the light-emitting element 20 is greater than the shortest distance d4 between the second surface 42 and the light-emitting element 20.

[0076] As shown in FIG. 5, the inner surface 16 of the wall portion 12 of the base 10 of the light-emitting device 101 has, in a cross-sectional view, a first surface 41 continuing from the upper surface 15 of the bottom portion 11, a second surface 42 located above the first surface 41, a third surface 43 connecting the upper end of the first surface 41 and the lower end of the second surface 42, a fourth surface 44 located above the second surface 42, and a fifth surface 45 connecting the upper end of the second surface 42 and the lower end of the fourth surface 44. The shortest distance d4 between the second surface 42 and the light-emitting element 20 is greater than the shortest distance d3 between the first surface 41 and the light-emitting element 20. The shortest distance d5 between the fourth surface 44 and the light-emitting element 20 is greater than the shortest distance d4 between the fourth surface 44 and the light-emitting element 20. The first surface 41, the second surface 42, the third surface 43, the fourth surface 44, and the fifth surface 45 are connected as described above to form two steps on the inner surface 16 of the wall portion. By providing two steps on inner surface 16 of the wall portion, inner surface 16 of the wall portion can be covered with a smaller amount of light reflective member 30 than when no steps are provided on inner surface 16 of the wall portion. Also, similar to light emitting device 100 according to embodiment 1, it is possible to prevent light reflective member 30 from creeping up during manufacture of the light emitting device, particularly creeping up onto upper surface 12a of the wall portion.

[0077] The first surface 41 may be disposed substantially perpendicular to the upper surface 15 of the bottom portion 11. Similarly, the second surface 42 and the fourth surface 44 may be disposed substantially perpendicular to the upper surface 15 of the bottom portion 11.

[0078] The upper end of the first surface 41 and the lower end of the second surface 42 are located at substantially the same height with respect to the upper surface 15 of the bottom 11. That is, the third surface 43 connecting the upper end of the first surface 41 and the lower end of the second surface 42 can be disposed approximately parallel to the upper surface 15 of the bottom 11. The upper end of the second surface 42 and the lower end of the fourth surface 44 are located at substantially the same height with respect to the upper surface 15 of the bottom 11. That is, the fifth surface 45 connecting the upper end of the second surface 42 and the lower end of the fourth surface 44 can be disposed approximately parallel to the upper surface 15 of the bottom 11.

[0079] In the light emitting device 101 of the second embodiment, the upper end of the fourth surface 44 coincides with the inner peripheral edge of the upper surface 12a of the wall portion.

[0080] In a cross-sectional view, the shortest distance d4 between the second surface 42 and the light-emitting element 20 is greater than the shortest distance d3 between the first surface 41 and the light-emitting element 20. In other words, in a cross-sectional view, the second surface 42 is located outside the base 10 relative to the first surface 41. Typically, the difference between the shortest distance d4 and the shortest distance d3 (i.e., the shortest distance d4−shortest distance d3) is the same as the width w2 of the third surface 43.

[0081] In a cross-sectional view, the shortest distance d5 between the fourth surface 44 and the light-emitting element 20 is greater than the shortest distance d4 between the second surface 42 and the light-emitting element 20. In other words, in a cross-sectional view, the fourth surface 44 is located outside the base 10 relative to the second surface 42. Typically, the difference between the shortest distance d5 and the shortest distance d4 (i.e., the shortest distance d5-shortest distance d4) is the same as the width w3 of the fifth surface 45.

[0082] The shortest distance d3 between the first surface 41 and the light emitting element 20 is not particularly limited, but may be preferably 0.2 mm or more, more preferably 0.3 mm or more. By setting the shortest distance d3 in this range, the space between the first surface 41 and the light emitting element 20 is widened, and the degree of freedom in arranging the light reflective member 30 is improved. As a result, the space between the light reflective member 30 and the side surface of the light emitting element 20 is widened, and the light emitted from the side surface of the light emitting element 20 is easily extracted to the outside of the light emitting device 101 without being reflected by the light reflective member 30 and entering the light emitting element 20 again, so that the light extraction efficiency of the light emitting device 101 can be further improved. In addition, the shortest distance d3 is not particularly limited, but may be preferably 2.0 mm or less, more preferably 1.0 mm or less. By setting the shortest distance d3 in this range, it becomes easy to miniaturize the light emitting device 101. In one embodiment, the distance d3 may be 0.2 mm or more and 2.0 mm or less, preferably 0.3 mm or more and 1.0 mm or less, for example, 0.6 mm or more and 0.8 mm or less.

[0083] The ratio (h0 / d3) of the distance h0 between the upper surface 12a of the wall portion of the base and the upper surface 15 of the bottom portion 11 to the shortest distance d3 between the first surface 41 and the light emitting element 20 may be preferably 0.5 or more, more preferably 1.0 or more, and even more preferably 1.2 or more. By setting the ratio of the distance h0 to the shortest distance d1 within the above range, the distance between the inner surface 16 of the wall portion 11 and the light emitting element 20 becomes closer, and the light emitting device 101 can be easily miniaturized. In addition, the ratio (h0 / d3) of the distance h0 to the shortest distance d3 may be preferably 10.0 or less, more preferably 6.0 or less, and even more preferably 3.0 or less. By setting the ratio of the distance h0 to the shortest distance d3 to 10.0 or less, the light emitted from the side surface of the light emitting element 20 is not reflected by the light reflective member 30 arranged on the first surface 41, and it becomes easier to extract the light to the outside of the light emitting device 101, so that the light extraction efficiency of the light emitting device 101 can be further improved. In one embodiment, the ratio of the distance h0 to the shortest distance d1 (h0 / d3) can be 0.5 or more and 10.0 or less, preferably 1.0 or more and 6.0 or less, and more preferably 1.2 or more and 3.0 or less.

[0084] The width w2 of the third surface 43 in the cross-sectional view is not particularly limited, but may be preferably 0.01 mm or more, more preferably 0.05 mm or more. By setting the width w2 of the third surface 43 to the above range, it is possible to further suppress the creeping up of the light reflective member during manufacturing. Furthermore, the width w2 of the third surface 43 is not particularly limited, but may be preferably 2.0 mm or less, more preferably 1.0 mm or less. By setting the width w2 of the third surface 43 to the above range, it is possible to increase the ratio of the space in the recess in the light emitting device 101, thereby improving the degree of freedom in the arrangement of the light reflective member 30. As a result, it is possible to secure a wide space between the light reflective member 30 and the side surface of the light emitting element 20, so that the light emitted from the side surface of the light emitting element 20 can be easily taken out to the outside of the light emitting device 101 without being reflected by the light reflective member 30 and re-entering the light emitting element 20. In one embodiment, the width w2 of the third surface 43 may be 0.01 mm or more and 2.0 mm or less, preferably 0.05 mm or more and 1.0 mm or less.

[0085] The width w3 of the fifth surface 45 in the cross-sectional view is not particularly limited, but may be preferably 0.01 mm or more, more preferably 0.02 mm or more. By setting the width w3 of the fifth surface 45 in the above range, it is possible to further suppress the creeping up of the light reflective member during manufacturing. Furthermore, the width w3 of the fifth surface 45 is not particularly limited, but may be preferably 2.0 mm or less, more preferably 1.0 mm or less. By setting the width w3 of the fifth surface 45 in the above range, it is possible to increase the ratio of the space in the recess in the light emitting device 101, thereby improving the degree of freedom in the arrangement of the light reflective member 30. As a result, it is possible to secure a wide space between the light reflective member 30 and the side surface of the light emitting element 20, so that the light emitted from the side surface of the light emitting element 20 can be easily taken out to the outside of the light emitting device 101 without being reflected by the light reflective member 30 and re-entering the light emitting element 20. In one embodiment, the width w3 of the fifth surface 45 may be 0.01 mm or more and 2.0 mm or less, preferably 0.02 mm or more and 1.0 mm or less.

[0086] In a cross-sectional view, the width w2 of the third surface 43 may be larger than the width w3 of the fifth surface 45. For example, in an arbitrary cross section perpendicular to the upper surface 15 of the bottom 11 and passing through the center of the upper surface 15 of the bottom 11, the width w2 of the third surface 43 is larger than the width w3 of the fifth surface 45. By making the width w2 of the third surface 43 larger than the width w3 of the fifth surface 45, the first surface 41 can be covered with a smaller amount of the light reflective member 30 than when no step is arranged on the inner surface 16 of the wall portion 12. As a result, it becomes easier to adjust the inclination of the surface of the light reflective member 30 while reducing the amount of the light reflective member 30 used during manufacturing.

[0087] The ratio (w2 / w3) of the width w2 of the third surface 43 to the width w3 of the fifth surface 45 may be preferably 0.1 or more, more preferably 0.2 or more, and even more preferably 0.3 or more. The ratio (w2 / w3) of the width w2 of the third surface 43 to the width w3 of the fifth surface 45 may be preferably 10.0 or less, more preferably 8.0 or less, and even more preferably 6.0 or less. In one embodiment, the ratio (w2 / w3) of the width w2 of the third surface 43 to the width w3 of the fifth surface 45 may be 0.1 or more and 10.0 or less, preferably 0.2 or more and 8.0 or less, and even more preferably 0.3 or more and 6.0 or less.

[0088] The shortest distance d4 between the second surface 42 and the light-emitting element 20 may be the shortest distance d3 plus the width w2 of the third surface 43. The shortest distance d5 between the fourth surface 44 and the light-emitting element 20 may be the shortest distance d4 plus the width w3 of the fifth surface 45.

[0089] In a cross-sectional view, the fifth surface 45 of the wall 12 is located at the same height as the upper surface 24 of the light-emitting element 20 or lower than the upper surface 24 of the light-emitting element 20. In other words, the distance h6 between the upper end of the second surface 42 and the upper surface 15 of the bottom 11 is the same as the distance h10 between the upper surface 24 of the light-emitting element 20 and the upper surface 15 of the bottom 11, or is smaller than the distance h10 between the upper surface 24 of the light-emitting element 20 and the upper surface 15 of the bottom 11. Preferably, the fifth surface 45 of the wall 12 is located lower than the upper surface 24 of the light-emitting element 20. By arranging the fifth surface 45 of the wall 12 at the same height as the upper surface 24 of the light-emitting element 20 or lower than the upper surface 24 of the light-emitting element 20, the light emitted from the light-emitting element 20 and directed upward from the wall 12 is easily emitted directly from the light-emitting device 101 without being reflected by the light-reflective member 30. That is, a wide linear optical path is ensured between the side surface of the light-emitting layer of the light-emitting element 20 and the inner edge of the upper surface 12a of the wall portion 12. Therefore, the proportion of light emitted from the light-emitting element 20 that is directly emitted upward from the light-emitting device 101 without being reflected by the light-reflective member 30 increases, and the light extraction efficiency of the light-emitting device 101 can be improved.

[0090] In a cross-sectional view, the difference between the distance h10 between the upper surface 24 of the light-emitting element 20 and the upper surface 15 of the bottom 11 and the distance h6 between the upper end of the second surface 42 and the upper surface 15 of the bottom 11 is not particularly limited. The difference between the distance h10 between the upper surface 24 of the light-emitting element 20 and the upper surface 15 of the bottom 11 and the distance h6 between the upper end of the second surface 42 and the upper surface 15 of the bottom 11 may be, for example, 0.01 mm or more, preferably 0.02 mm or more. By setting the difference between the distance h10 and the distance h6 to the above range, the light extraction efficiency of the light-emitting device 101 can be further increased. In addition, the difference between the distance h10 and the distance h6 is not particularly limited, but may be preferably 1.0 mm or less, more preferably 0.5 mm or less. In one embodiment, the difference between the distance h10 and the distance h6 may be 0.01 mm or more and 1.0 mm or less, preferably 0.02 mm or more and 0.5 mm or less.

[0091] In a cross-sectional view, distance h3 between the upper end of first surface 41 and upper surface 15 of bottom 11 may be greater than distance h4 between the upper end of second surface 42 and third surface 43. By making distance h3 greater than distance h4, the proportion of h3 on inner surface 16 of the wall portion increases, and the position of third surface 43 becomes higher, so that creeping up of light reflective member 30 can be suppressed at a higher position. This allows light reflective member 30 to be disposed at a higher position.

[0092] In a cross-sectional view, the ratio (h3 / h4) of the distance h3 between the upper end of the first surface 41 and the upper surface 15 of the bottom portion 11 to the distance h4 between the upper end of the second surface 42 and the third surface 43 may be preferably 0.5 or more, more preferably 0.7 or more, and even more preferably 0.9 or more. By increasing the ratio of the distance h3 to the distance h4, it becomes easier to form the light reflective member to a higher position. In addition, the ratio (h3 / h4) of the distance h3 to the distance h4 may be preferably 1.5 or less, more preferably 1.3 or less, and even more preferably 1.1 or less. By decreasing the ratio of the distance h3 to the distance h4, the distance between the third surface 43 and the upper surface 12a of the wall portion becomes large, and the light reflective member can be more effectively prevented from creeping up to the upper surface 12a of the wall portion. In one embodiment, the ratio (h3 / h4) of the distance h3 to the distance h4 may be 0.5 or more and 1.5 or less, preferably 0.7 or more and 1.3 or less, and even more preferably 0.9 or more and 1.1 or less.

[0093] In a cross-sectional view, the distance h4 between the upper end of the second surface 42 and the third surface 43 may be greater than the distance h5 between the upper end of the fourth surface 44 and the fifth surface 45. By making the distance h4 greater than the distance h5, the position of the fifth surface 45 becomes higher. Since the fifth surface 45 suppresses the light reflective member 30 from creeping up to the upper surface 12a of the wall portion 12 during the manufacture of the light emitting device, the light reflective member 30 is typically formed up to the vicinity of the inner edge of the fifth surface 45. Therefore, in the case where the fifth surface 45 is provided, the higher the fifth surface 45 is located, the easier it is to form the light reflective member 30 to a higher position.

[0094] In a cross-sectional view, the ratio (h4 / h5) of the distance h4 between the upper end of the second surface 42 and the third surface 43 to the distance h5 between the upper end of the fourth surface 44 and the fifth surface 45 may be preferably 1.01 or more, more preferably 1.2 or more, and even more preferably 1.5 or more. By setting the ratio of the distance h4 to the distance h5 in the above range, it becomes easy to form the light reflecting member at a position higher than the light reflecting member. In addition, the ratio (h4 / h5) of the distance h4 to the distance h5 may be preferably 5.0 or less, more preferably 3.0 or less, and even more preferably 2.0 or less. By setting the ratio of the distance h4 to the distance h5 in the above range, the distance between the fifth surface 45 and the upper surface 12a of the wall portion becomes large, and the light reflecting member 30 can be further suppressed from creeping up to the upper surface 12a of the wall portion. In one embodiment, the ratio of the distance h4 to the distance h5 (h4 / h5) can be 1.01 or more and 5.0 or less, preferably 1.2 or more and 3.0 or less, and more preferably 1.5 or more and 2.0 or less.

[0095] Like the base material 13 in the light emitting device 100 according to the first embodiment, the base material 13 in the light emitting device 101 according to the second embodiment may have a laminated structure. For example, the base material 13 may be a laminate of a first layer, a second layer, a third layer, and a fourth layer. In such an embodiment, the first layer may constitute the bottom portion 11, and the second layer, the third layer, and the fourth layer may constitute the wall portion 12. A part of the second layer constitutes the first surface 41 and the third surface 43. A part of the third layer constitutes the second surface 42 and the fifth surface 45. A part of the fourth layer constitutes the fourth surface 44 and the upper surface 12a of the wall portion. Each layer may further have a laminated structure constituted by a plurality of layers.

[0096] As shown in FIG. 5, in the light-emitting device 101 of embodiment 2, the light-reflective member 30 is continuously arranged on a portion of the upper surface 15 of the bottom 11, the entire surface of the first surface 41, the entire surface of the third surface 43, the entire surface of the second surface 42, the entire surface of the fifth surface 45, and a portion of the fourth surface 44, and is arranged so as not to contact the upper end of the fourth surface 44.

[0097] In the light emitting device of the present disclosure, the arrangement of the light reflective member 30 is not limited to the example shown in Fig. 5. For example, the light reflective member 30 may be arranged continuously on a part of the upper surface 15 of the bottom 11, the entire first surface 41, the entire third surface 43, the entire second surface 42, and a part of the fifth surface 45, and may not be arranged on the fourth surface 44. In addition, the light reflective member 30 may be arranged continuously on a part of the upper surface 15 of the bottom, the entire first surface 41, the entire third surface 43, and the second surface 42, and may not be arranged on the fifth surface 45 and the fourth surface 44.

[0098] The distance between the upper end of the fourth surface 44 and the upper end 30a of the light reflective member 30 may be preferably 0.05 mm or more, more preferably 0.1 mm or more, and even more preferably 0.15 mm or more. By setting the distance within the above range, the amount of light that is emitted directly to the outside of the light emitting device 101 without being reflected by the light reflective member 30 out of the light traveling from the light emitting element 20 toward the upper side of the wall portion 12 is increased, thereby improving the light extraction efficiency of the light emitting device 101. In addition, the distance between the upper end of the fourth surface 44 and the upper end 30a of the light reflective member 30 may be preferably 0.5 mm or less, more preferably 0.4 mm or less, and even more preferably 0.3 mm or less. By setting the distance within the above range, a wider range of the inner surface 16 of the wall portion can be covered by the light reflective member 30, improving the light extraction efficiency of the light emitting device.

[0099] Modifications of the light emitting devices according to the first and second embodiments of the present disclosure will be described below.

[0100] <Variation 1> Fig. 7 shows a cross-sectional view of the light emitting device taken along line VII-VII shown in Fig. 6. As shown in Fig. 6, the light emitting device of Modification 1 has a substantially rectangular external shape of the third surface 43 in a top view. Also, as shown in Fig. 7, in the light emitting device of Modification 1, in a cross-sectional view, the distance h11 between the third surface 43 at the center of each side and the upper surface 15 of the bottom is smaller than the distances h12 and h13 between the third surface 43 at the end of each side and the upper surface 15 of the bottom.

[0101] Fig. 8 shows a cross-sectional view of the light emitting device cut along the line VIII-VIII shown in Fig. 6. As shown in Fig. 6, in the light emitting device of Modification 1, the outer shape of the fifth surface 45 is substantially rectangular in top view, and as shown in Fig. 8, in the cross-sectional view, the distance h21 between the fifth surface 45 at the center of each side and the upper surface 15 of the bottom is smaller than the distances h22 and h23 between the fifth surface 45 at the end of each side and the upper surface 15 of the bottom.

[0102] As a first modification of the second embodiment, both the height of the third surface and the height of the fifth surface may satisfy the above, or only one of them may satisfy the above.

[0103] <Variation 2> In the light emitting device of Modification 2, the outer shape of third surface 43 is substantially rectangular in top view. In the light emitting device of Modification 2, light reflective member 30 is disposed on third surface 43, and the thickness of light reflective member 30 on third surface 43 at the center of each side of third surface 43 is greater than the thickness of light reflective member 30 on third surface 43 at the end of each side of third surface 43.

[0104] In the light emitting device of Modification 2, the outer shape of fifth surface 45 is substantially rectangular in top view. In the light emitting device of Modification 2, light reflective member 30 is disposed on fifth surface 45, and the thickness of light reflective member 30 on fifth surface 45 at the center of each side of fifth surface 45 is thicker than the thickness of light reflective member 30 on third surface 43 at the end of each side of fifth surface 45.

[0105] In addition, as a second variant of embodiment 2, both the thickness of the light-reflective member 30 on the third surface 43 and the thickness of the light-reflective member 30 on the fifth surface 45 may satisfy the above, or only one of them may satisfy the above.

[0106] It is preferable to combine Modification 1 and Modification 2. For example, in a cross-sectional view, the distance h11 between the third surface 43 at the center of each side and the upper surface 15 of the bottom is smaller than the distances h12 and h13 between the third surface 43 at the end of each side and the upper surface 15 of the bottom. Also, the light reflective member 30 is disposed on the third surface 43, and the thickness of the light reflective member 30 on the third surface 43 at the center of each side of the third surface 43 is thicker than the thickness of the light reflective member 30 on the third surface 43 at the end of each side of the third surface 43. Moreover, in a top view, the outer shape of fifth surface 45 is substantially rectangular, and in a cross-sectional view, a distance h21 between fifth surface 45 at the center of each side and upper surface 15 of the bottom is smaller than distances h22, h23 between fifth surface 45 and upper surface 15 of the bottom at the end of each side of fifth surface 45. Moreover, light reflective member 30 is disposed on fifth surface 45, and the thickness of light reflective member 30 on fifth surface 45 at the center of each side of fifth surface 45 is thicker than the thickness of light reflective member 30 on fifth surface 45 at the end of each side of fifth surface 45.

[0107] This specification includes the following embodiments. 1. a base having a recess defined by a bottom and a wall located on the bottom; A light emitting element disposed within the recess; a light reflective member disposed continuously on an upper surface of the bottom portion and an inner surface of the wall portion within the recess of the base; Including, In cross section, the inner surface of the wall portion has a first surface continuing from an upper surface of the bottom portion, a second surface located above the first surface, and a third surface connecting an upper end of the first surface and a lower end of the second surface, the shortest distance between the second surface and the light-emitting element is greater than the shortest distance between the first surface and the light-emitting element, the third surface is located at the same height as an upper surface of the light-emitting element or lower than an upper surface of the light-emitting element; The upper end of the light reflective member is located below the upper surface of the wall portion. Light emitting device. 2. 2. The light emitting device of claim 1, wherein the distance between the top end of the first surface and the top surface of the bottom is greater than the distance between the top end of the second surface and the third surface. 3. 3. The light emitting device according to claim 1 or 2, wherein the light reflective member is arranged on the upper surface of the bottom, the first surface, the third surface, and the second surface so as not to contact the upper end of the second surface. 4. The light-emitting device described in any one of 1 to 3 above, wherein the inner surface of the wall portion further has a fourth surface located above the second surface and a fifth surface connecting an upper end of the second surface and a lower end of the fourth surface, and the shortest distance between the fourth surface and the light-emitting element is greater than the shortest distance between the second surface and the light-emitting element. 5. the third surface is located below an upper surface of the light-emitting element, 5. The light emitting device according to claim 4, wherein the fifth surface is located at the same height as an upper surface of the light emitting element or lower than an upper surface of the light emitting element. 6. 6. The light emitting device according to claim 4 or 5, wherein the distance between an upper end of the second surface and the third surface is greater than the distance between an upper end of the fourth surface and the fifth surface. 7. 7. The light emitting device according to any one of claims 4 to 6, wherein in any cross section perpendicular to the upper surface of the bottom and passing through the center of the upper surface of the bottom, the width of the third surface is larger than the width of the fifth surface. 8. The light emitting device described in any one of claims 4 to 7, wherein the light reflective member is arranged on the upper surface of the bottom, the first surface, the third surface, the second surface, the fifth surface, and the fourth surface so as not to contact the upper end of the fourth surface. 9. When viewed from above, the third surface has a substantially rectangular shape, 9. The light emitting device described in any one of 1 to 8 above, wherein, in a cross-sectional view, the distance between the third surface at the center of each side and the upper surface of the bottom is smaller than the distance between the third surface at the end of each side and the upper surface of the bottom. 10. the light reflective member is disposed on the third surface, 10. The light emitting device described in claim 9, wherein the thickness of the light reflective material on the third surface at the center of each side of the third surface is thicker than the thickness of the light reflective material on the third surface at the end of each side of the third surface. 11. When viewed from above, the fifth surface has a substantially rectangular shape, 9. The light emitting device described in claim 8, wherein, in a cross-sectional view, the distance between the fifth surface at the center of each side and the upper surface of the bottom is smaller than the distance between the fifth surface at the end of each side and the upper surface of the bottom. 12. the light reflective member is disposed on the fifth surface, 12. The light emitting device described in claim 11, wherein the thickness of the light reflective material on the fifth surface at the center of each side of the fifth surface is thicker than the thickness of the light reflective material on the third surface at the end of each side of the fifth surface. 13. 13. The light emitting device according to any one of the above 1 to 12, wherein the distance between the surface of the light reflective member and the light emitting element increases from the lower part of the wall portion toward the upper part of the wall portion. 14. The light emitting device has a substrate and a semiconductor structure underlying the substrate, 14. The light-emitting device according to any one of claims 1 to 13, wherein, in a cross-sectional view, the light-reflective member is located below a straight line connecting the upper end of the inner surface of the wall portion and the lower end of the side of the light-emitting element that faces the upper end of the inner surface of the wall portion. 15. 15. The light emitting device according to any one of 1 to 14 above, wherein the light reflective member is spaced apart from the light emitting element when viewed from above. 16. 16. The light emitting device according to any one of the above 1 to 15, further comprising a light transmissive member disposed on the base, the light transmissive member and the light reflective member being spaced apart from each other. [Explanation of symbols]

[0108] 100, 101...light-emitting device, 10...base, 10x, 10y...side surface of base, 11...bottom, 12...wall, 12a...upper surface of wall, 13...base material, 14...recess, 15...upper surface of bottom, 16...inner surface of wall, 17...wiring layer, 18...lower surface of bottom, 19...external electrode, 20...light-emitting element, 21...substrate, 22...semiconductor layer, 23...electrode, 24...upper surface of light-emitting element, 30...light reflecting member, 30a...upper end of light reflecting member, 41...Side 1, 42...Side 2, 43...Side 3, 44...Side 4, 45...Side 5, 50...Translucent member, 51...Joining member

Claims

1. a base having a bottom and a wall; a light-emitting element disposed on an upper surface of the bottom; a wiring layer disposed on an upper surface of the bottom and electrically connected to the light emitting element; a light-reflecting member disposed on an upper surface of the bottom portion and an inner surface of the wall portion of the base, the light-reflecting member including a light-reflecting material, silica, and an alkali metal; Including, In cross section, the inner surface of the wall portion has a first surface continuing from the upper surface of the bottom portion, a second surface having a lower end positioned at the same position as the upper end of the first surface or higher than the upper end of the first surface, and a third surface connecting the upper end of the first surface and the lower end of the second surface, the second surface is located outside the base body relative to the first surface, an upper end of the light reflecting member is located below an upper surface of the wall portion; the light reflective member is disposed on a side surface of the wiring layer, and is not disposed on an upper surface of the wiring layer; Light-emitting device.

2. The light emitting device according to claim 1 , wherein an outer edge of the wiring layer is located between an outer edge of the light emitting element and the first surface.

3. 3. The light emitting device according to claim 1, wherein the light reflecting material is boron nitride or aluminum oxide.

4. The light emitting device according to claim 1 , wherein the light emitting element emits ultraviolet light.

5. 3. The light-emitting device according to claim 1, wherein a plurality of light-emitting elements are disposed on the bottom of the base.

6. The light emitting device has a substrate and a semiconductor structure underlying the substrate; 3. The light-emitting device according to claim 1, wherein, in a cross-sectional view, the light-reflecting member is located below a straight line connecting an upper end of the inner surface of the wall portion and a lower end of a side surface of the light-emitting element that faces the upper end of the inner surface of the wall portion.

7. The light emitting device according to claim 1 , further comprising a light-transmitting member disposed on the base, the light-transmitting member and the light-reflecting member being spaced apart from each other.

8. When viewed from above, the third surface has a substantially rectangular outer shape, 3. The light-emitting device according to claim 1, wherein, in a cross-sectional view, a distance between the third surface at the center of each side and an upper surface of the bottom is smaller than a distance between the third surface at the end of each side and an upper surface of the bottom.

9. the light reflecting member is disposed on the third surface, 3. The light emitting device according to claim 1, wherein the thickness of the light reflective material on the third surface at the center of each side of the third surface is thicker than the thickness of the light reflective material on the third surface at the end of each side of the third surface.

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