JP6934712B2 - Semiconductor light emitting device and vehicle lighting equipment - Google Patents

Description

The present invention relates to a semiconductor light emitting device and a vehicle lamp that irradiate light from a light emitting element by converting it into light having a desired wavelength by a wavelength conversion member.

A semiconductor light emitting device is known in which light emitted from a semiconductor light emitting element is wavelength-converted by a wavelength conversion member to irradiate white light. Such a semiconductor light emitting device is used as a light source for lighting equipment such as general lighting, street lights, and vehicle lighting equipment. In particular, since vehicle lighting equipment and the like are required to have high front brightness, various semiconductor light emitting devices are used. Has been proposed.

For example, Patent Document 1 includes at least a light emitting element, a light converting member having a light emitting surface exposed to the outside and a side surface continuous from the light emitting surface and converting the light from the light emitting element into wavelength, and a light reflecting material. A light emitting device having improved front luminance is disclosed by providing a covering member that covers a side surface of the light conversion member so that substantially only the light emitting surface is used as a light emitting region in the light emitting device.

Further, in Patent Document 2, a wavelength conversion member having a surface larger than the upper surface of the light emitting element is bonded to the upper surface of the light emitting element, and the upper surface of the wavelength conversion member has a translucency having a larger area than the upper surface of the light emitting element. A member is arranged, a side light guide member is provided from the side surface of the light emitting element to the lower surface of the peripheral edge of the wavelength conversion member, and at least a light reflection member is provided on each side surface of the wavelength conversion member, the translucent member, and the side light guide member. The front brightness was improved by arranging the wavelength conversion member so that the upper surface of the wavelength conversion member was smaller than the lower surface of the translucent member or the region outside the light emitting element was formed thinner than the region directly above the light emitting element. A semiconductor light emitting device is disclosed.

Japanese Patent No. 552682 Japanese Unexamined Patent Publication No. 2016-72515

However, in the semiconductor light emitting device of Patent Document 1 described above, since a coating member containing a light reflecting material is provided so as to surround the light emitting element, light from the side surface of the light emitting element is blocked. The side emission of the light cannot be effectively utilized, and the luminous efficiency is lowered. Further, when the light conversion member is larger than the light emitting element, the light emitted from the portion larger than the light emitting element of the light conversion member is emphasized by the wavelength-converted color as compared with the other portions, and the color unevenness on the light emitting surface. Will occur.
In the semiconductor light emitting device of Patent Document 2, since the wavelength conversion member has a surface larger than the upper surface of the light emitting element, color unevenness is likely to occur in the vicinity of the peripheral edge of the light emitting surface. Further, the light emitted from the side surface of the light emitting element has a longer distance to reach the wavelength conversion member than the light emitted from the upper surface of the light emitting element, so that the excitation light ratio is lowered.
In both Patent Document 1 and Patent Document 2, since the side surface of the light emitting element is covered with a light reflecting material, a frame-shaped non-light emitting region is generated in the vicinity of the peripheral edge of the light emitting surface, and the semiconductor light emitting device cannot be miniaturized. ..

The present invention has been made in view of the above circumstances, and an object of the present invention is to improve luminous efficiency and suppress color unevenness on a light emitting surface.

One aspect of the present invention includes a light emitting element having a light emitting surface on the upper surface and side surfaces, a first phosphor layer containing a phosphor and directly or indirectly covering the upper surface of the light emitting element, and the first. A second phosphor layer containing a phosphor having a concentration lower than that of the phosphor layer of No. 1 and covering at least the side surface of the light emitting element, and the upper surfaces of the first phosphor layer and the second phosphor layer. Provided is a semiconductor light emitting device, which comprises a light transmitting substrate which is arranged and has an area larger than the upper surface of the light emitting element, and a light reflecting member which covers at least the side surface of the second phosphor layer.

In the semiconductor light emitting device, a first phosphor layer is provided on the upper surface of the light emitting element, and a second phosphor layer is provided from the side surface of the light emitting element to the side surface and the upper surface of the first phosphor layer. , The light transmissive substrate may be provided on the upper surface of the second phosphor layer.
Further, a second phosphor layer is provided from the side surface of the light emitting element to the upper surface emitting surface of the light emitting element and the side surface of the first phosphor layer, and the first phosphor layer is the second phosphor layer. The light transmissive substrate may be provided on the upper surface and the light transmissive substrate may be provided on the upper surface of the first phosphor layer.

In addition, another aspect of the present invention includes a support substrate, a light emitting element having a light emitting layer provided on the upper surface of the support substrate, and a phosphor, and a first phosphor provided on the upper surface of the light emitting layer. A second phosphor layer containing a layer and a phosphor having a concentration lower than that of the first phosphor layer, and covering the side surface of the light emitting layer, the side surface of the first phosphor layer, and the upper surface of the support substrate. A light transmissive substrate arranged on the upper surface of the first phosphor layer and the second phosphor layer and having an area larger than the upper surface of the light emitting element, and at least the side surface of the second phosphor layer. Provided is a semiconductor light emitting device including a light reflecting member covering the above.
Furthermore, another aspect of the present invention provides a vehicle lamp equipped with the above-mentioned semiconductor light emitting device.

According to the present invention, it is possible to improve the luminous efficiency and suppress color unevenness on the light emitting surface.

A schematic configuration of the semiconductor light emitting device according to the first embodiment of the present invention is shown, (A) is a cross-sectional view, and (B) is a top view. (A) to (F) are explanatory views which outline the process of manufacturing the semiconductor light emitting device which concerns on 1st Embodiment of this invention. (A) to (H) are explanatory views which show the outline of another process which manufactures the semiconductor light emitting device which concerns on 1st Embodiment of this invention. (A) and (B) are cross-sectional views showing a schematic configuration of the semiconductor light emitting device according to the first modification of the first embodiment of the present invention. A schematic configuration of the semiconductor light emitting device according to the second embodiment of the present invention is shown, (A) is a cross-sectional view, and (B) is a top view. (A) to (E) are explanatory views which outline the process of manufacturing the semiconductor light emitting device which concerns on 2nd Embodiment of this invention. It is sectional drawing which shows the semiconductor light emitting apparatus which concerns on 1st Embodiment and 2nd Embodiment of this invention, (A) is the example which included the spacer 131 in the 2nd phosphor layer 13. , (B) show an example in which the spacer 131 is not included in the second phosphor layer 13. It is a top view which shows the schematic structure of the semiconductor light emitting device which concerns on the 1st Embodiment and 2nd Embodiment of this invention. A schematic configuration of a semiconductor light emitting device according to a first embodiment and another modification of the second embodiment of the present invention is shown, and FIG. 9A is a cross-sectional view taken along the line AA of FIG. 9B. ) Is a top view. (A) and (B) are top views showing an example of a case where a dicing cut is performed on the semiconductor light emitting device according to the first embodiment and the second embodiment of the present invention and each modification. A schematic configuration of a semiconductor light emitting device according to a third embodiment of the present invention is shown, (A) is a cross-sectional view, and (B) is a top view. A schematic configuration of the semiconductor light emitting device according to the third embodiment of the present invention is shown, (A) is a cross-sectional view, and (B) is a top view. It is a top view which shows the schematic structure of the semiconductor light emitting device which concerns on another example of 3rd Embodiment of this invention. (A) to (F) are explanatory views which outline the process of manufacturing the semiconductor light emitting device which concerns on 3rd Embodiment of this invention. (A) to (H) are explanatory views which show the outline of another process which manufactures the semiconductor light emitting device which concerns on 3rd Embodiment of this invention. (A) to (E) are explanatory views which show the outline of another process which manufactures the semiconductor light emitting device which concerns on 4th Embodiment of this invention. It is a top view which shows the schematic structure of the semiconductor light emitting device which concerns on the 3rd Embodiment of this invention and the modification of 4th Embodiment. It is sectional drawing which shows the schematic structure of the semiconductor light emitting device which concerns on the 3rd Embodiment of this invention and the modification of 4th Embodiment, (A) is the case where the light emitting element is a flip chip type, (B) is light emitting. The case where the element is a wire bonding type is shown. (A) and (B) are cross-sectional views showing a schematic configuration of a semiconductor light emitting device according to another example of each embodiment of the present invention.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the drawings shown below, hatching is appropriately omitted even in the cross-sectional view for easy understanding and improvement of visibility. Further, in the following description, even when different embodiments or modifications are made, the same reference numerals are given to the same configurations, and the description thereof will be omitted.

(First Embodiment)
The semiconductor light emitting device according to the first embodiment of the present invention will be described.
The semiconductor light emitting device according to the present embodiment includes a light emitting element 10 having a light emitting surface on the upper surface and side surfaces, and a first phosphor layer 12 containing a phosphor and directly or indirectly covering the upper surface of the light emitting element 10. , A second phosphor layer 13, which contains a phosphor having a concentration lower than that of the first phosphor layer 12 and covers at least the side surface of the light emitting element 10, and a first phosphor layer 12 and a second phosphor. It includes a light transmitting substrate 14 which is arranged on the upper surface of the layer 13 and has an area larger than the upper surface of the light emitting element 10, and a light reflecting member 14 which covers at least the side surface of the second phosphor layer 14.

More specifically, FIG. 1A is a cross-sectional view of the semiconductor light emitting device according to the present embodiment, and FIG. 1B is a top view. As shown in FIG. 1, the semiconductor light emitting device 1 includes a light emitting element 10, a mounting substrate 11 on which the light emitting element 10 is mounted, a first phosphor layer 12, a second phosphor layer 13, and light transmittance. It includes a substrate 14.
In the top view of the semiconductor light emitting device shown in the following description, a configuration that cannot be visually recognized from the top view is shown by a broken line, and hatching or the like is added for convenience of explanation.

The light emitting element 10 has a rectangular shape when viewed from above, and has a flip-chip structure in which a semiconductor layer (not shown) and a light emitting layer 102 are laminated on a transparent substrate 101 and an electrode for feeding is formed and inverted. doing. The light emitting element 10 irradiates the light emitted from the light emitting layer 102 to the outside via the upper surface 101A and the side surface 101B of the transparent substrate 101. Therefore, in the light emitting element 10, the upper surface 101A and the side surface 101B of the transparent substrate 101 serve as light emitting surfaces.
The electrodes of the light emitting element 10 are conducted by bumps 16 to a wiring pattern (described later) on the mounting substrate 11. For the bump 16, a bump made of Au or an alloy thereof, eutectic solder (AuSn), PbSn, lead-free solder, or the like can be used. Further, instead of the bump 16, for example, a conductive paste or the like may be used.

In the present embodiment, the mounting substrate 11 is a plate-shaped body made of a ceramic material, and a plate-shaped substrate made of aluminum nitride is applied. The substrate is generally formed of an insulating material such as glass epoxy, resin, or ceramics, or a composite material of an insulating material and a metal member. As the substrate, those using ceramics or thermosetting resin having high heat resistance and weather resistance are preferable.
A wiring pattern (not shown) is formed on the mounting board 11. The wiring pattern is mainly formed on the surface of the mounting substrate 11 as a mounting pattern of the light emitting element 10 and a current routing pattern for supplying power to the light emitting element 10. As the wiring pattern, a conductive material such as Al, Ni, Cu, Ag, Au or the like can be used.

The first phosphor layer 12 contains a phosphor that converts the light emitted from the light emitting element 10 into light having a desired wavelength, and is provided on the upper surface of the light emitting element 10. More specifically, on the first phosphor layer 12, for example, a phosphor-dispersed resin (screen printing, attaching a semi-curing sheet, etc.), a fluorescent-dispersed glass via a transparent adhesive, a fluorescent ceramic plate, or the like is used. Can be applied. In the present embodiment, since the light emitting element 10 emits light from the upper surface and the side surface of the transparent substrate 11, the first phosphor layer 12 is substantially arranged on the upper surface of the transparent substrate 11. Further, it is preferable that the first phosphor layer 12 has substantially the same size as the light emitting surface on the upper surface of the light emitting element 10 or a size slightly smaller than that.

The second phosphor layer 13 contains a phosphor having a concentration lower than that of the first phosphor layer, and is provided so as to cover at least the side surface of the light emitting element 10. In the present embodiment, the side surface of the light emitting element 10 is provided. Therefore, it is provided over the side surface and the upper surface of the first phosphor layer 12. The second phosphor layer 13 is, for example, a spherical bead having a uniform particle size made of a phosphor adjusted to a predetermined concentration and a spacer 131 for gap adjustment (glass, silicone resin, or the like, and has a particle size gap). It is composed of a silicone resin containing (which fulfills the adjustment function).

The thickness of the portion of the second phosphor layer 13 located above the first phosphor layer 12 is adjusted via the spacer 131, and the light emitting element 10 is subjected to surface tension with the lower surface of the light transmissive substrate 14 described later. It is adjusted to a fillet shape (reverse taper shape) that covers the side surface and the side surface of the first phosphor layer 12. The fillet-shaped inverted tapered surface (inclined surface) may be curved. Further, as the spacer 131 for adjusting the gap, for example, spherical silicone beads (Hypressica TSN6NTA manufactured by Ube Exsymo Co., Ltd., etc.) can be applied.

The light transmissive substrate 14 is made of, for example, glass, sapphire, silicone resin, etc., has an area larger than the upper surface of the light emitting element, and is arranged on the upper surface of the second phosphor layer.
The light reflecting member 15 is provided so as to cover the side surface of the light transmitting substrate 14 and the side surface of the second phosphor layer 13, and to expose the upper surface of the light transmitting substrate 14 to the outside.

(Production method)
Subsequently, a method of manufacturing the semiconductor light emitting device configured as described above will be described with reference to FIG. In FIG. 2, for convenience of explanation, the light emitting body layer, the transparent substrate, and the like of the light emitting element 10 are not shown.
A flip-chip type light emitting element 10 is mounted via an Au bump 16 on a mounting substrate 11 on which a wiring pattern (not shown) is formed in advance (FIG. 2A).
A semi-cured phosphor sheet having substantially the same size as the upper surface of the light emitting element 10 whose phosphor concentration and thickness have been adjusted in advance is mounted on the upper surface of the light emitting element 10 and heat-welded to form a first phosphor layer (FIG. 2). (B)).

As the second phosphor layer 13, a mixed solution in which a phosphor and a gap adjusting spacer 131 are mixed in advance with a silicone resin at a predetermined concentration is applied to the upper surface of the first phosphor layer 12 in a predetermined amount so as to be convex. (Fig. 2 (C)). At this time, the coating amount of the second phosphor layer 13 is the light emitting element between the lower surface of the light transmissive substrate 14 and the first phosphor layer 12 when the light transmissive substrate 14 of the next step is mounted. The amount is adjusted so as to cover the side surface of 10 and the side surface of the first phosphor layer and maintain the fillet shape.

Next, the light transmissive substrate 14 larger than the size of the light emitting element 10 is mounted on the second phosphor layer 13 coated in a convex shape, so that the light transmissive substrate 14 is coated in a convex shape. The phosphor layer 13 of 2 is crushed, and a fillet-shaped second phosphor layer 13 is formed so as to protrude from between the first phosphor layer 12 and the light transmissive substrate 14 to the side surface (FIG. 2 (D). ), (E)). By heating at this stage, the semi-curable first phosphor layer 12, the second phosphor layer 13, and the silicone resin containing the spacer are simultaneously cured.

Next, a predetermined amount of a light-reflecting filler (for example, titanium oxide, aluminum oxide, zirconium oxide, zinc oxide, etc., 20 wt% of titanium oxide in this embodiment) mixed with a silicone resin in advance is mixed on the mounting substrate 11 to transmit light. A structure in which the light reflecting member 15 covers the side surface of the light transmissive substrate 14 and the side surface of the second phosphor layer 13 by pouring until the side surface of the sex substrate 14 is completely covered, heat-curing, and dicing cut to a predetermined size. It is possible to manufacture an individualized semiconductor light emitting device (FIG. 2 (F)).

(Other manufacturing methods)
Next, another manufacturing method according to the above-mentioned semiconductor light emitting device will be described with reference to FIG. In FIG. 3, for convenience of explanation, the light emitting layer, the transparent substrate, and the like of the light emitting element 10 are not shown.
A plurality of flip-chip type light emitting elements 10 are mounted via Au bumps on a mounting substrate 11 on which a wiring pattern (not shown) is formed in advance (FIG. 3 (A)). Next, as the first phosphor layer 12, a semi-cured phosphor sheet having the same size as the upper surface of the light emitting element 10 whose phosphor concentration and thickness have been adjusted in advance is mounted on the upper surface of each light emitting element and heat-welded (. FIG. 3 (B). Next, as the second phosphor layer 13, a predetermined amount of a mixed solution in which a phosphor is mixed with a silicone resin at a predetermined concentration is applied to the upper surface of each of the first phosphor layers 12 so as to be convex (FIG. 3 (C)). At this time, the coating amount is adjusted so that the second phosphor layer 13 has a fillet shape.

Next, the light transmissive substrate 14 larger than the outermost size of the plurality of light emitting elements 10 is mounted on the second phosphor layer 13 coated in a convex shape, so that the light transmissive substrate 14 is convex. The uncured second phosphor layer 13 coated on the surface is crushed, and the fillet-shaped second phosphor layer 13 protrudes from between the first phosphor layer 12 and the light transmissive substrate 14 to the side surface. It is formed (FIG. 3 (D). At this time, the fillet shape is formed, and at the same time, the second phosphor layer 13 is formed between the lower surface of the light transmissive substrate 14 and the first phosphor layer 12. Is adjusted to the thickness of about one layer of the phosphor particles (FIG. 3 (E)). By heat-curing at this stage, the semi-cured first phosphor layer 12 and the second phosphor The silicone resin containing the layer 13 is cured at the same time.

Next, the light-transmitting member 15 covers the side surface of the light-transmitting substrate 14 and the side surface 13 of the second phosphor layer, and is heat-cured (FIG. 3 (F)). A dicing cut is performed from the light transmissive substrate 14 side with the target of the boundary where the second phosphor layer 12 reaches the lower surface of the light transmissive substrate 14 in a fillet shape (FIGS. 3 (G) and 3 (H)). At this time, since the upper surface of the first phosphor layer 12 and the upper surface of the second phosphor layer 13 can be aligned using the image recognition camera through the light transmissive substrate 14, the stage of the dicing apparatus can be moved at a predetermined pitch. When doing so, the alignment of the cut line can be performed accurately. By dicing cut in this way, it is possible to obtain an individualized semiconductor light emitting device in which the light reflecting member does not exist in the top view, which is particularly effective for miniaturization of the device.

The semiconductor light emitting device configured in this way irradiates light having a desired wavelength as follows.
Of the light emitted from the light emitting element 10, the light from the light emitting surface of the upper surface 101A and the light from the light emitting surface of the side surface 101B are irradiated to the outside via different optical paths. That is, the light from the light emitting surface 101A on the upper surface of the light emitting element 10 is wavelength-converted by the first phosphor layer 12 and the second phosphor layer 13 having substantially the same size as the upper surface 101A of the light emitting element 10, and is light transmissive. It passes through the substrate 14 and is irradiated from the upper surface of the light-transmitting substrate 14.

Further, the light from the light emitting surface of the light emitting element 10 side surface 101B is wavelength-converted by the second phosphor layer 12, reflected by the light reflecting member 15 and transmitted through the light transmitting substrate 14, and the light transmitting substrate 14 is transmitted. It is irradiated from the top surface.
In this way, both the light from the light emitting surface of the upper surface 101A of the light emitting element 10 and the light from the light emitting surface of the side surface 101B are emitted from the upper surface of the light transmissive substrate 14. Therefore, the light from the side surface of the light emitting element 10 can be efficiently taken out from the upper surface of the light transmissive substrate 14, and the front luminance can be improved.

The second phosphor layer 13 can adjust the chromaticity of the entire semiconductor light emitting device by adjusting the phosphor concentration. Specifically, by combining the phosphor concentration and thickness of the first phosphor layer 12 and the phosphor concentration, thickness (= spacer wavelength) and fillet amount of the second phosphor layer 13, by combining the three. The amount of wavelength conversion between the upper surface and the side surface of the light emitting element 10 can be made substantially the same, and the color of the light extracted from the upper surface of the light transmissive substrate 14 can be made uniform.

In particular, in the present embodiment, the concentration of the phosphor layer contained in the second phosphor layer 13 is lower than that of the first phosphor layer 12, and the thickness of the second phosphor layer 13 is adjusted by the spacer 131. .. Therefore, although the light from the side surface 101B of the light emitting element 10 has a long optical path to the light transmitting substrate, the light is emitted from the upper surface 101A of the light emitting element 10 and is wavelength-converted by the first phosphor layer 12 to be light. It is converted to almost the same color as the light emitted from the transmissive substrate. Therefore, the amount of wavelength conversion between the upper surface and the side surface of the light emitting element 10 can be made substantially the same, and the color of the light emitted from the upper surface of the light transmissive substrate 14 can be made uniform.

(Modification 1 of the first embodiment)
In FIGS. 1 and 2 in the first embodiment described above, the light transmissive substrate 14 is formed into a rectangular shape, and the side surface thereof is processed so as to be perpendicular to the mounting substrate.
As shown in FIG. 4A, the side surface of the light transmissive substrate 14 has a tapered shape having an inclination so as to spread toward the upper surface, and has an inclined surface continuous from the side surface of the second phosphor layer 13. can do. At this time, the inclination angle between the side surface of the light transmissive substrate 14 and the side surface of the second phosphor layer 13 can be appropriately determined, but it is preferable that the inclination angles of both are equal.

By doing so, the light from the light emitting element is reflected by the tapered side surface and guided to the front surface of the light emitting surface (see the arrow in FIG. 4 (A)), so that the light extraction efficiency is improved and the front surface of the light emitting surface is improved. It is possible to further suppress the color unevenness in the above and realize uniform light emission. As a comparative example, as shown in FIG. 4B, when the side surface of the light transmissive substrate 14 is not processed into a tapered shape, a part of the light from the light emitting element is emitted as shown by the arrow in the figure. Since it is reflected on the side surface and returns to the light transmissive substrate, the luminous efficiency is slightly lower than that of the semiconductor light emitting device shown in FIG. 4 (A).

(Second Embodiment)
Next, the semiconductor light emitting device according to the second embodiment of the present invention will be described.
FIG. 5A is a cross-sectional view of the semiconductor light emitting device according to the present embodiment, and FIG. 5B is a top view. In the following description, the same components as those in the first embodiment described above will be designated by the same reference numerals, and the description thereof will be omitted.
In the semiconductor light emitting device according to the present embodiment, the second light emitting layer 13 is provided on the upper surface of the light emitting element 10, and the first light emitting layer 12 is provided on the upper surface of the second light emitting layer 13. It differs from the above-described first embodiment and its modifications in that the light emitting layer 13 does not include the spacer 131.

A method of manufacturing the semiconductor light emitting device configured as described above will be described with reference to FIG. In FIG. 5, for convenience of explanation, the light emitting body layer, the transparent substrate, and the like of the light emitting element 10 are not shown.
The flip-chip type light emitting element 10 is mounted on the mounting substrate 11 on which the wiring pattern is formed in advance via Au bumps (FIG. 6 (A)). Next, as the second phosphor layer 13, a mixed solution in which a phosphor is mixed with a silicone resin at a predetermined concentration is applied to the upper surface of the light emitting element 10 in a predetermined amount so as to be convex (FIG. 6 (B)). At this time, the coating amount adjustment for forming the second phosphor layer 13 into a fillet shape is adjusted in the same manner as in the first embodiment.

Next, as the first phosphor layer 12, a semi-cured phosphor sheet whose phosphor concentration and thickness have been adjusted in advance is attached to the lower surface of the light transmissive substrate 14, and the convex second phosphor. It is mounted on a layer (Fig. 6 (C)). At this time, the convexly applied second phosphor layer 13 is crushed, and a fillet shape is formed so as to protrude from the space between the first phosphor layer 12 and the illuminant layer 10 to form a fillet, and at the same time, light is emitted. A second phosphor layer 13 is formed between the upper surface of the element 10 and the first phosphor layer 12 so as to have a thickness of about one layer of phosphor particles (FIG. 6 (D)).
By heat-curing in this state, the silicone resin containing the semi-cured first phosphor layer 12 and the second phosphor layer 13 is simultaneously cured. Next, the light reflecting member 15 covers the side surface of the light transmissive substrate 14 and the side surface of the second phosphor layer 13, is heat-cured, and is diced to a predetermined size to form a semiconductor light emitting device. It can be manufactured ((FIG. 6 (E)).

In the above example, the lower surface of the light transmissive substrate 14 is flat, and by laminating the first phosphor layer 12 in advance, the first phosphor layer 12 protrudes from the lower surface of the light transmissive substrate 14. (See FIGS. 5 and 6).
Instead, as shown in FIG. 7, the first phosphor layer 12 is embedded in the lower surface of the light transmissive substrate 14, and the lower surface of the first phosphor layer 12 is formed from the peripheral edge of the light transmissive substrate 14. It can also be processed so that it becomes a continuous flat surface. Note that FIG. 7A shows an example in which the second phosphor layer 13 contains the spacer 131, and FIG. 7B shows an example in which the second phosphor layer 13 does not contain the spacer 131. There is.
By embedding the first phosphor layer in the lower surface of the light transmissive substrate to form an integrated plate-shaped member, for example, a plurality of types of plate-shaped members can be created in response to variations in the emission wavelength of the element. By selecting and mounting an appropriate plate-shaped member according to the mounted light emitting element, the emission color of the semiconductor light emitting device can be easily adjusted.

(Modified examples of the first embodiment and the second embodiment)
In the first embodiment and the second embodiment described above, as shown in FIGS. 1A and 1B, all four sides of the rectangular light emitting element 10 are located inside the light transmissive substrate 14. A second phosphor layer 13 on the fillet is provided so as to surround the light emitting element 10.
In the semiconductor light emitting device according to this modification, as shown in FIG. 8, one side of the light emitting element 10, the first phosphor layer 12, the second phosphor layer 13, and the light transmissive substrate 14 is the upper surface of the light emitting surface. All of them are formed so as to be located on the same straight line when viewed from the viewpoint.
As described above, by providing one side of the light emitting element 10, the first phosphor layer 12, the second phosphor layer 13, and the light transmissive substrate 14 on the same straight line when viewed from the light emitting surface, the brightness of the straight line is high. Therefore, among vehicle lamps, it can be used as a light source that makes it easy to create a light distribution that enhances distant visibility, especially when used as a light source for head lamps.

(Other variants of the first embodiment and the second embodiment)
In the first embodiment and the second embodiment described above, as shown in FIGS. 1A and 1B, the light reflecting member 15 is provided up to the side surface of the rectangular light transmitting substrate 14. 9 (A) is a cross-sectional view taken along the line AA of FIG. 9 (B). The light reflecting member 15 is provided on the side surfaces of the pair of opposite sides of the 14 and the light reflecting member 15 is not provided on the side surfaces of the other pair of sides. By doing so, when a plurality of semiconductor light emitting devices are arranged side by side, the distance between the light emitting surfaces of the semiconductor light emitting devices can be brought close to each other.
The semiconductor light emitting device according to this modification can be obtained, for example, by dicing cut at the upper end portion of the fillet-shaped second phosphor layer 13 as shown by the broken lines in FIGS. 10A and 10B. ..

(Third Embodiment)
The semiconductor light emitting device according to the third embodiment of the present invention will be described. In the following description, the same components as those in the first embodiment described above will be designated by the same reference numerals, and the description thereof will be omitted.
The semiconductor light emitting device according to the present embodiment contains a support substrate 201, a light emitting element 20 having a light emitting layer 202 provided on the upper surface of the support substrate, and a phosphor, and a first fluorescence provided on the upper surface of the light emitting layer. A second fluorescence containing the body layer 12 and a phosphor having a concentration lower than that of the first phosphor layer 12 and covering the side surface of the light emitting layer 202, the side surface of the first phosphor layer 12, and the upper surface of the support substrate 201. A light transmissive substrate 14 arranged on the upper surfaces of the body layer 13, the first phosphor layer 12 and the second phosphor layer 13 and having a larger area than the upper surface of the light emitting element 30, and at least the second phosphor. A light reflecting member 15 that covers the side surface of the layer 13 is provided.

FIG. 11A is a cross-sectional view of the semiconductor light emitting device according to the present embodiment, and FIG. 11B is a top view. 12A and 12B are views showing a state in which the light transmissive substrate 14 of FIG. 11 is removed, FIG. 12A is a cross-sectional view of the semiconductor light emitting device, and FIG. 12B is a top view.
More specifically, in the semiconductor light emitting device according to the present embodiment, as the light emitting element 20, the semiconductor light emitting layer 202 is attached to the opaque support substrate 201 via a metal layer (not shown), and the upper surface of the light emitting element 20 and the light emitting element 20 are attached. A light emitting element having a metal bonding structure that conducts from the back surface is applied.

Therefore, bonding pads are formed on the upper surface of the light emitting element 20 and at predetermined positions of the mounting substrate 11, and the bonding pad 203 provided on the upper surface of the light emitting element 20 and the bonding pad (not shown) of the mounting substrate 11 Are electrically connected by a bonding wire 5. In the light emitting element 20, since the light of the semiconductor light emitting layer 202 is mainly emitted from the upper surface of the light emitting element, the front luminance is further increased as compared with the flip-chip type light emitting element shown in each of the above-described embodiments and modifications thereof. can do.

The first phosphor layer 12 preferably has a size that does not interfere with the wire bonding region on the upper surface of the light emitting element 20, and is formed in a size slightly smaller than that of the semiconductor light emitting layer 202 in the present embodiment. The second phosphor layer 13 is composed of a phosphor and a silicone resin containing a spacer 131 adjusted in advance to a predetermined concentration, and the second phosphor layer 13 is located above the first phosphor layer 12 by the spacer 131. The thickness of the is adjusted. Further, the light-transmitting substrate 14 is larger than the size of the light-emitting element 20, and due to the surface tension with the lower surface of the light-transmitting substrate 14, the light-transmitting element 20 other than the region where the first phosphor layer 12 is arranged A fillet-shaped (reverse-tapered) second phosphor layer 13 that covers the upper surface and the side surface of the first phosphor layer 12 is formed. The light reflecting member 15 is formed so as to cover the side surface of the light transmitting substrate 14, the side surface of the second phosphor layer 13, and the side surface of the light emitting element 20, and to expose the upper surface of the light transmitting substrate 14.

Here, the semiconductor light emitting layer 202 bonded on the opaque support substrate 201 is smaller than the size of the opaque support substrate 201. This is because when a semiconductor substrate manufactured by a semiconductor process in a wafer state is divided in a dicing process, it is necessary to arrange a semiconductor light emitting layer inside which is not affected by the machined grooves on the end face, which is a minimum on the outer periphery of the support substrate. This is because the non-light emitting part remains.

In FIGS. 11 and 12, the size of the first phosphor layer 12 is smaller than that of the semiconductor light emitting layer 202. For example, as shown in FIG. 13, the semiconductor light emitting layer 202 and the first phosphor layer 12 are formed. It may be substantially the same size. In this case, the structure may be such that a part of the first phosphor layer 12 is cut out so as not to interfere with the wire bonding region arranged on the upper surface of the element. The amount of wavelength conversion on the upper surface of the light emitting element is achieved by combining the phosphor concentration and thickness of the first phosphor layer with the phosphor concentration, thickness (= spacer particle size) and fillet amount of the second phosphor layer. Can be made substantially the same, and the color of the light extracted from the upper surface of the light-transmitting substrate can be made uniform. Further, the spacer 131 does not necessarily have to be included, and the spacer 13 may not be included in the second phosphor 13.

In the semiconductor light emitting device configured as described above, among the light emitted from the light emitting element 20, the light incident on the first phosphor layer 12 is the first phosphor layer 12 and the first phosphor layer 12. The wavelength is converted by the second phosphor layer 13 located on the upper part of the. Further, the light on the upper surface of the light emitting element 20 and the light leaking from the side surface of the semiconductor light emitting layer 202 other than the region where the first phosphor layer 12 is arranged are wavelength-converted by the second phosphor layer 13. In this way, all the light emitted from the semiconductor light emitting layer 202 can be efficiently guided to the upper surface of the light transmissive substrate 14 and taken out, so that the front luminance can be improved while suppressing color unevenness. .. Since the light of the semiconductor light emitting layer 202 is emitted from the upper surface of the device, the light from the first phosphor layer 12 and the fillet-shaped second phosphor layer 13 is emitted in the same direction, and both lights are transmitted. Since it is efficiently taken out on the upper surface of the sex substrate, the front brightness can be further increased as compared with the semiconductor light emitting element to which the above-mentioned flip chip type light emitting element is applied. The phosphor concentration of the second phosphor layer 13 is lower than that of the phosphor contained in the first phosphor layer 12, thereby adjusting the chromaticity of the entire semiconductor light emitting device.

A method for manufacturing such a semiconductor light emitting device will be described with reference to FIG.
A metal bonding type light emitting element is mounted on a mounting substrate 11 on which a wiring pattern (not shown) is formed in advance via AuSn eutectic and Au wire (FIG. 14 (A)). Next, as the first phosphor layer 12, a semi-cured phosphor sheet smaller than the upper surface size of the light emitting element 20 whose phosphor concentration and thickness have been adjusted in advance is mounted on the upper surface of the light emitting element 20 and heat-welded ( FIG. 14 (B).

Next, as the second phosphor layer 13, a predetermined amount of a mixed solution obtained by previously mixing a silicone resin with a phosphor and a gap adjusting spacer 131 at a predetermined concentration is applied to the upper surface of the first phosphor layer 12 and the upper surface of the light emitting element 20. It is applied so as to be convex (FIG. 14 (C)). At this time, the coating amount of the second phosphor layer 13 is the light emitting element between the lower surface of the light transmissive substrate 14 and the first phosphor layer 12 when the light transmissive substrate 14 is mounted in the next step. The amount of the second phosphor layer 13 that can maintain the fillet shape is adjusted so as to cover the upper surface of the 20 and the side surface of the first phosphor layer 12.

Next, by mounting the light transmissive substrate 14 larger than the size of the light emitting element 20 on the convex second phosphor layer 13, a fillet shape is formed in a reverse taper shape (D) (D). E). By heat-curing here, the semi-curable first phosphor layer 12, the second phosphor layer 13, and the silicone resin containing the spacer 131 are simultaneously cured. Next, a predetermined amount of a light-reflecting filler mixed with a silicone resin is poured into the mounting substrate 11 as a light-reflecting member 15 until the side surface of the light-transmitting substrate 14 is completely covered, and heat-cured. By dicing and cutting the cured product to a predetermined size, the light reflecting member 15 is individualized as a structure covering the side surface of the light transmitting substrate 14, the side surface of the second phosphor layer 13, and the side surface of the light emitting element 20. The semiconductor light emitting device is obtained (FIG. 14 (F)).

(Other manufacturing methods)
A plurality of metal bonding type light emitting elements 20 are mounted on a mounting substrate 11 on which a wiring pattern (not shown) is formed in advance via AuSn eutectic and Au wire (FIG. 15 (A)). As the first phosphor layer 12, a semi-cured phosphor sheet smaller than the size of the upper surface of the light emitting element 20 whose phosphor concentration and thickness have been adjusted in advance is mounted on the upper surface of each light emitting element 20 and heat-welded (FIG. 15 (FIG. 15). B)). Next, as the second phosphor layer, a mixed solution in which a phosphor is mixed with a silicone resin at a predetermined concentration is applied to the upper surface of the first phosphor layer 12 and the upper surface of the light emitting element 20 in a predetermined amount so as to be convex. do. Here, the coating amount is appropriately adjusted to maintain the fillet shape (FIG. 15 (C)).

Next, a fillet shape is formed by mounting the light transmissive substrate 14 larger than the outermost outer size of the plurality of light emitting elements 20 on the convex second phosphor layer 13 (FIG. 15 (D). )). The convexly applied second phosphor layer 13 is crushed to form a fillet shape protruding from the side surface between the first phosphor layer 12 and the light emitting body layer 10, and at the same time, the upper surface of the light emitting element 10 is formed. A second phosphor layer 13 is formed between the first phosphor layer 12 and the first phosphor layer 12 so as to have a thickness of about one layer of phosphor particles (FIG. 15 (E)). By heat-curing at this stage, the silicone resin containing the semi-cured first phosphor layer 12 and the second phosphor layer 13 is simultaneously cured. The light reflecting member 15 covers the side surface of the light transmitting substrate 14, the side surface of the second phosphor layer 13, and the side surface of the light emitting element 20, and is heat-cured (FIG. 15 (F)). A dicing cut is performed from the light transmissive substrate 14 side (FIG. 15 (G)) with the target of the boundary where the second phosphor layer 13 reaches the lower surface of the light transmissive substrate 14 in a fillet shape, and the second phosphor layer 13 is separated into individual pieces. A semiconductor light emitting device can be obtained (FIG. 15 (H)).

At this time, the upper surface of the first phosphor layer 12, the upper surface of the second phosphor layer 13, and the wire bonding portion can be aligned through the light transmissive substrate 14 by using an image recognition camera, so that the dicing apparatus can be used. When moving the stage at a predetermined pitch, the alignment of the cut line can be performed accurately. By dicing cut in this way, it is possible to obtain an individualized semiconductor light emitting device in which the light reflecting member does not exist in the top view, which is particularly effective for miniaturization of the device.

(Fourth Embodiment)
Next, the semiconductor light emitting device according to the fourth embodiment of the present invention will be described.
By forming the first phosphor layer 12 on the lower surface of the light transmissive substrate 14 in advance, a predetermined amount of the second phosphor layer 13 is applied to the upper surface of the light emitting element 20, and the first fluorescence is applied from above. By joining to the lower surface of the body layer 12, a region of the lower surface of the light transmissive substrate 14 that does not come into contact with the first phosphor layer 12, the lower surface of the first phosphor layer 12, and the first phosphor layer 12 A fillet-shaped second phosphor layer can be formed to cover the side surface of the light emitting element 20 and the region not bonded to the first phosphor layer 12 on the upper surface of the light emitting element 20. Even with such a configuration, the concentration of the phosphor sandwiched between the upper surface of the light emitting element 20 and the light transmissive substrate 14 is the same as that of the third embodiment described above, and the fluorescence of the second phosphor layer 13 By adjusting the body concentration, it is possible to adjust the chromaticity of the entire semiconductor light emitting device.

The manufacturing method of the semiconductor light emitting device configured as described above will be described with reference to the drawings. Note that in FIG. 16, for convenience of explanation, the semiconductor light emitting body layer and the like of the light emitting element 20 are not shown.
A metal bonding type light emitting element 20 is mounted on a mounting substrate 11 on which a wiring pattern (not shown) is formed in advance via AuSn eutectic and Au wire (FIG. 16A). Next, as the second phosphor layer, a mixed solution in which a phosphor is mixed with a silicone resin at a predetermined concentration is applied to the upper surface of the light emitting element in a predetermined amount so as to be convex (FIG. 16B). Next, a small semi-cured phosphor sheet whose phosphor concentration and thickness have been adjusted in advance is bonded to the lower surface of the light transmissive substrate 14 and mounted on the convex second phosphor layer 13. (FIG. 16 (C)).

At this time, the convexly applied second phosphor layer 13 is crushed, and a fillet shape is formed so as to protrude from the space between the first phosphor layer 12 and the illuminant layer 10 to form a fillet, and at the same time, light is emitted. A second phosphor layer 13 is formed between the upper surface of the element 10 and the first phosphor layer 12 so as to have a thickness of about one layer of phosphor particles (FIG. 16 (D)). By heat-curing at this stage, the semi-cured first phosphor layer 12 and the silicone resin containing the second phosphor layer 13 are simultaneously cured. Next, the light reflecting member 15 is provided so as to cover the side surface of the light transmissive substrate 14, the side surface of the second phosphor layer 13, and the side surface of the light emitting element 20, and is heat-cured and diced to a predetermined size. As a result, an individualized semiconductor light emitting device is obtained (FIG. 16 (E)).

(Modification example)
In the third embodiment and the fourth embodiment described above, as shown in FIGS. 11 to 13, all four sides of the rectangular light emitting element 20 are located inside the light transmissive substrate 14, and the light emitting element 10 is located. A second phosphor layer 13 on the fillet is provided so as to surround the periphery of the fillet.
As shown in FIG. 17, the semiconductor light emitting device according to this modification has a light emitting surface on three sides of the light emitting element 20, the first phosphor layer 12, the second phosphor layer 13, and the light transmissive substrate 14. All are formed so as to be located on the same straight line when viewed from the upper surface.
In this way, by providing the three sides of the light emitting element 20, the first phosphor layer 12, the second phosphor layer 13, and the light transmissive substrate 14 on the same straight line when viewed from the light emitting surface, a plurality of light emitting elements 20 are provided in a horizontal row. When the semiconductor light emitting devices of the above are arranged side by side, it is possible to make the brightness uniform with respect to the side-by-side light emission.

In the structure of the semiconductor light emitting device described above, as a method for further improving the front luminance, as shown in FIGS. 18A and 18B, light shielding films 18 can be provided on the four side surfaces of the semiconductor light emitting device. As a method of forming the light-shielding film 18, a large number of light-shielding films 18 are arranged side by side with the side surfaces facing the upper surface, and a metal reflective film (for example, Al, Ag, Ag / Pd, Ag / Ni, etc.) or dielectric is used using a vacuum device. Examples thereof include a method of forming a body multilayer film. Further, there is also a method in which the upper surface of the light transmissive substrate 14 is covered with a resist film, four side surfaces are simultaneously formed by using a rotation mechanism, and then the resist film is removed. As another method for forming the light-shielding film, a method of fixing the white pigment ink by an inkjet method, electrolytic plating using a seed layer as a base, and the like can be mentioned. The formation of the light-shielding film has the effect of returning the light from the side surface of the light-reflecting member, the side surface of the second phosphor layer 13, and the side surface of the light-transmitting substrate 14 to the inside, and is taken out to the front by reflection and scattering. The front brightness can be improved.

Further, like the semiconductor light emitting device shown in FIGS. 8 and 17, one side of any one of the light emitting element, the first phosphor layer, the second phosphor layer, and the light transmissive substrate is located on the same straight line. In addition, the light-shielding film 18 can be provided even when the structure is such that the light-reflecting member 15 does not exist in the top view.
Specifically, for example, in the semiconductor light emitting device shown in FIG. 8, among the four sides of the light transmissive substrate, the sides of the light emitting element, the first phosphor layer, and the second phosphor layer are formed in the same linear shape. There is a light-shielding film 18 provided on the side surface where these are continuous. That is, since at least one side surface of the four side surfaces of the light transmissive substrate is on the same side surface as the side surface of the first phosphor layer and the side surface of the light emitting element and forms a continuous side surface, the side surface is shielded from light. A curtain 18 is provided. As a result, the brightness in the vicinity of the light-shielding film 18 on the light emitting surface can be made higher than in other regions. Therefore, the brightness distribution inclination in the vertical direction can be formed, and in the light distribution of the headlamp for a vehicle, it is possible to realize an ideal light distribution having a gradation on the road surface at the same time as forming a light / dark cut line.

In the semiconductor light emitting device shown in FIG. 17, when at least three side surfaces of the four side surfaces of the light transmissive substrate form the same creepage surface as the first phosphor layer side surface and the light emitting element side surface, respectively. By providing the light-shielding film 18 on the creeping surface, the brightness in the vicinity of the light-shielding film on the light emitting surface can be made higher than that of other regions. At the same time, when semiconductor light emitting devices are arranged in a line shape or a matrix shape and turned on and off, the light from an adjacent light source is not guided by the light shielding film, cross talk is prevented, and a high contrast light distribution can be created. It will be possible.

In each of the above-described embodiments and modifications thereof, the light emitting element has been described as a flip chip type and a metal bonding type, but any one capable of forming a fillet structure of the second phosphor layer on the upper surface or the side surface of the light emitting element. It is adaptable. Further, the light transmissive substrate may have a wavelength conversion function. For example, the same effect can be obtained by adjusting the ratio of the phosphor (wavelength converter) contained in the first and second phosphor layers and the light transmissive substrate.
Further, by mixing the light scattering material with the first and second phosphor layers, more uniform light scattering becomes possible and color unevenness can be suppressed.

Further, as shown in FIG. 19, the structure may be such that one surface of the upper surface or the lower surface of the light transmissive substrate is angled. In the case of the example shown in FIG. 19A, the upper surface of the first phosphor layer 12 and the lower surface of the light transmissive substrate 14 have the same size, and the inclination angle of the lower surface of the light transmissive substrate 14 is advantageous for light extraction. Become. The outer shape of the first phosphor layer 12 can be processed at the same time as the processing of the inclined surface, and the process can be simplified.

In the case of the example shown in FIG. 19B, the upper surface of the light transmissive substrate 14 can be made the same size as or smaller than the light emitting element 20, which is advantageous for improving the front luminance. Further, in the manufacturing method of individualizing shown in FIGS. 3 (H), 15 (H), and 18, if a plurality of light emitting elements are mounted with a close interval, the brightness difference between adjacent semiconductor light emitting devices is different. It is also possible to provide a semiconductor light emitting device which is arranged in a line shape or a matrix shape.

The semiconductor light emitting device according to each of the above-described embodiments and modifications can be applied to a light source of a headlamp or an ADB (Adaptive Driving Beam) type vehicle lighting device, and is also applied to a general lighting device for lighting or the like. You can also do it.

10 ... light emitting element, 11 ... mounting substrate, 12 ... first phosphor layer, 13 ... second phosphor layer, 14 ... light transmissive substrate, 15 ... light Reflective member, 16 ... Bump, 18 ... Light-shielding film, 20 ... Light emitting element, 102 ... Light emitting layer, 202 ... Semiconductor light emitting layer

Claims (12)

A light emitting element having a light emitting surface on the upper surface and the side surface,
A first phosphor layer containing a phosphor and directly or indirectly covering the upper surface of the light emitting device,
A second phosphor layer containing a phosphor having a concentration lower than that of the first phosphor layer and covering at least the side surface of the light emitting element.
A light transmissive substrate which is arranged on the upper surface of the first phosphor layer and the second phosphor layer and has an area larger than the upper surface of the light emitting element .
Light reflecting member and
Equipped with a light-shielding film,
The second phosphor layer forms a fillet shape from the side surface of the light emitting element toward the lower surface of the light transmissive substrate.
The light reflecting member covers the fillet-shaped side surface of the second phosphor layer.
The light-shielding film covers the side surface of the light-reflecting member and the side surface of the light-transmitting substrate , and is made of a metal reflective film or a dielectric multilayer film.
A semiconductor light emitting device characterized in that the light reflecting member does not exist when the light transmitting substrate is viewed from above. The first phosphor layer is provided on the upper surface of the light emitting element, and the first phosphor layer is provided on the upper surface of the light emitting element.
The second phosphor layer is provided from the side surface of the light emitting element to the side surface and the upper surface of the first phosphor layer.
The semiconductor light emitting device according to claim 1, wherein the light transmissive substrate is provided on the upper surface of the second phosphor layer. The semiconductor light emitting device according to claim 1 or 2, wherein the light transmissive substrate has a tapered shape with its side surface inclined. The semiconductor light emitting device according to claim 2, wherein a recess is provided on the lower surface of the light transmissive substrate, and the recess is a plate-like member in which the first phosphor layer is fitted. The first phosphor layer is provided on the upper surface of the second phosphor layer,
The second phosphor layer is provided between the upper surface of the light emitting element and the first phosphor layer, the side surface of the light emitting element, and the side surface of the first phosphor layer.
The semiconductor light emitting device according to claim 1, wherein the light transmissive substrate is provided on the upper surface of the first phosphor layer. The semiconductor light emitting device according to any one of claims 1 to 5, wherein the light emitting element is a flip-chip type light emitting element in which a light emitting layer is laminated on a transparent substrate. A support substrate, a light emitting element having a light emitting layer provided on the upper surface of the support substrate, and a light emitting element.
A first phosphor layer containing a phosphor and provided on the upper surface of the light emitting layer,
A second phosphor layer containing a phosphor having a concentration lower than that of the first phosphor layer and covering the side surface of the light emitting layer, the side surface of the first phosphor layer, and the upper surface of the support substrate.
A light transmissive substrate which is arranged on the upper surface of the first phosphor layer and the second phosphor layer and has an area larger than the upper surface of the light emitting element.
Light reflecting member and
Equipped with a light-shielding film,
The second phosphor layer forms a fillet shape from the upper surface of the light emitting element toward the lower surface of the light transmissive substrate.
The light reflecting member is not covered the sides of the fillet shape of the second phosphor layer,
The light shielding film is not covered the sides and the side surface of the light transmissive substrate of the light reflecting member, and a metal reflection film or a dielectric multilayer film,
A semiconductor light emitting device , characterized in that the light reflecting member does not exist when the light transmitting substrate is viewed from above. The seventh aspect of claim 7, wherein the light emitting element is a wire bonding type light emitting element having the light emitting layer on the upper surface of the support substrate and supplying power to the light emitting layer via a bonding wire connected to the upper surface of the light emitting element. Semiconductor light emitting device.
Body light emitting device. The semiconductor light emitting device according to any one of claims 1 to 8, wherein the side surface of the second phosphor layer is an inclined surface extending toward the upper surface. The semiconductor light emitting device according to any one of claims 1 to 9, wherein the second phosphor layer contains a spacer. The semiconductor light emitting device according to any one of claims 1 to 10, wherein the first phosphor layer is formed to have substantially the same size as or smaller than the upper surface of the light emitting element. A vehicle lamp provided with the semiconductor light emitting device according to any one of claims 1 to 11.

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