JP2024061410A - Light-emitting device - Google Patents

Abstract

[Problem] To provide a light emitting device that reduces loss of light emitted from a light emitting element, prevents bleeding, and obtains high light output. [Solution] A semiconductor light emitting device 10 comprising a substrate 11 having two opposing main surfaces, a semiconductor light emitting element 20 arranged on the top surface, which is one of the main surfaces of the substrate 11, a light conversion member 22 arranged on the semiconductor light emitting element 20, and a first covering member 23 that covers the surface of the light conversion member 22 facing the semiconductor light emitting element 20 and the top surface of the substrate 11 and embeds the semiconductor light emitting element 20, the first covering member 23 extending outward from the outer periphery of the surface 22B of the light conversion member 22 facing the semiconductor light emitting element 20 while exposing the side surface of the light conversion member 22, the substrate 11 includes the light conversion member 22 and protrudes outward beyond the outer surface of the light conversion member 22 in a top view, and the light conversion member 22 includes the semiconductor light emitting element 20 and protrudes outward beyond the outer surface of the semiconductor light emitting element 20 in a top view. [Selected Figure] Figure 1B

Description

The present invention relates to a light-emitting device, in particular a light-emitting device that incorporates a semiconductor light-emitting element such as a light-emitting diode (LED).

Light emitting devices in which semiconductor light emitting elements are mounted are used in various lighting and display devices. In particular, in recent years, light emitting devices in which semiconductor light emitting elements are mounted are required to have further improved light emitting output and light emitting efficiency. In addition, high-output light emitting devices are required as light sources for vehicle headlights and the like.
Furthermore, there is a demand for miniaturization of light sources for backlighting of display devices.

For example, Patent Document 1 discloses a light emitting device including a light emitting element, a light guiding member that guides light emitted from the light emitting element to a light transmitting member, and a covering member that covers one surface of the light emitting element and the light transmitting member.
Furthermore, Patent Document 2 discloses a light emitting device including a case and an LED element having a laminate including a light emitting layer, in which the inside of the case is filled with a coating material.

JP 2010-219324 A JP 2007-19096 A

However, a light emitting device using a light transmitting member and a covering member has a problem in that light loss occurs.
The present invention has been made in view of the above-mentioned points, and has an object to provide a light emitting device that reduces loss of light emitted from a light emitting element and can obtain high light output.

A light emitting device according to one embodiment of the present invention comprises:
A substrate having two opposing main surfaces;
a semiconductor light emitting element disposed on an upper surface, which is one of the main surfaces of the substrate;
a light conversion member disposed on the semiconductor light emitting element;
a first covering member that covers a surface of the light conversion member facing the semiconductor light emitting element and an upper surface of the substrate and embeds the semiconductor light emitting element;
the first covering member extends outward from an outer periphery of a surface of the light converting member facing the semiconductor light emitting element while exposing a side surface of the light converting member,
the substrate includes the light converting member and protrudes outward beyond an outer surface of the light converting member when viewed from above;
The light conversion member includes the semiconductor light emitting element and protrudes outward beyond an outer surface of the semiconductor light emitting element when viewed from above.

1 is a conceptual diagram showing a light emitting device according to a first embodiment, and is a perspective view seen from above. 1B is a cross-sectional view taken along line AA shown in FIG. 1A. 1 is a conceptual diagram showing a light-emitting element according to a first embodiment. FIG. 2 is a conceptual diagram showing a light-emitting element. FIG. 2 is a conceptual diagram showing a light-emitting element. FIG. 13 is a conceptual diagram showing a state in which a light-emitting element is connected to a substrate and a light conversion member. 1 is a flowchart showing a method for manufacturing a light emitting device. 4 is a cross-sectional view showing a manufacturing process S1 of the light emitting device. 4 is a cross-sectional view showing a manufacturing process S2 of the light emitting device. 4 is a cross-sectional view showing a manufacturing process S3 of the light emitting device. FIG. 11 is a cross-sectional view showing a manufacturing process S4 of the light emitting device. 11 is a cross-sectional view showing a manufacturing process S5 of the light emitting device. 11 is a cross-sectional view showing a manufacturing process S6 of the light emitting device. FIG. 1 is a cross-sectional view showing a light emitting device according to a first modified example of the first embodiment. FIG. 11 is a cross-sectional view showing a light emitting device according to a second modified example of the first embodiment. FIG. 13 is a conceptual diagram showing a light-emitting device according to a second embodiment, and is a perspective view seen from above. FIG. 11 is a conceptual diagram showing a light emitting device according to a second embodiment before a light conversion member is installed and a first covering member is filled, and is a perspective view seen from above. FIG. 6B is a cross-sectional view taken along line BB shown in FIG. 6A.

In the following, preferred embodiments of the present invention will be described, which may be modified and combined as appropriate. In the following description and accompanying drawings, substantially the same or equivalent parts are designated by the same reference numerals.
[First embodiment]

Fig. 1A is a conceptual diagram showing a light emitting device 10 according to a first embodiment of the present invention, and is a perspective view seen from above. Fig. 1B is a cross-sectional view taken along line AA shown in Fig. 1A.
In this specification, the direction in which the light emitting element 20 is provided on the substrate 11 is referred to as the upper side, and the opposite direction is referred to as the lower side. In addition, the direction toward the center of the substrate 11 in a top view is referred to as the inward side, and the opposite direction is referred to as the outward side.

The light emitting device 10 has a substrate 11 with an upper surface and a lower surface, a light emitting element 20 mounted on the upper surface of the substrate 11, a light converting member 22 provided on the emission surface (upper surface) of the light emitting element 20 via an adhesive member 21 and having a lower surface 22B that is larger in area than the emission surface when viewed from above, and a reflective first covering member 23 that covers the side surfaces of the light emitting element 20 and adhesive member 21 and the lower surface of the light converting member 22.

(substrate)
A glass epoxy substrate (a glass fiber reinforced epoxy resin substrate) is used as _the substrate 11. The base of the substrate 11 may be an insulating ceramic substrate made of alumina ( _Al2O3 ), aluminum nitride (AlN), or the like.

The substrate 11 is formed in a rectangular plate shape with upper and lower surfaces that are opposing main surfaces. As shown in Figures 1A and 1B, when viewed from above, the substrate 11 is large enough to include the light conversion member 22, and all of the outer surfaces of the substrate 11 protrude outward beyond the outer surfaces of the light conversion member 22.

The substrate 11 is provided with a first wiring electrode 12A and a second wiring electrode 12B. The substrate 11 also has a first through electrode 28A and a second through electrode 28B, and a first mounting electrode 13A and a second mounting electrode 13B. Hereinafter, when the first wiring electrode 12A and the second wiring electrode 12B, the first through electrode 28A and the second through electrode 28B, and the first mounting electrode 13A and the second mounting electrode 13B are not to be distinguished from one another, they will simply be referred to as the wiring electrode 12, the through electrode 28, and the mounting electrode 13.

The upper surface of the substrate 11 is provided with first and second wiring electrodes 12A, 12B. The substrate 11 also has first and second through electrodes 28A, 28B that are electrically connected to the first and second wiring electrodes 12A, 12B, respectively. The lower surface of the substrate 11 is provided with a first mounting electrode 13A and a second mounting electrode 13B that are electrically connected to the first and second through electrodes 28A, 28B, respectively, and that are joined to a circuit board or the like (not shown).

Each of the first wiring electrode 12A and the second wiring electrode 12B has a light emitting element mounting area on which the light emitting element 20 is mounted, as well as a protective element placement area on which a protective element is mounted. A protective element (not shown) is mounted in parallel with the light emitting element 20 between the first wiring electrode 12A and the second wiring electrode 12B. The protective element prevents the light emitting element 20 from being damaged and becoming unlit due to abnormal voltage, and may be a Zener diode, a capacitor, or a varistor.

The first mounting electrode 13A and the second mounting electrode 13B are an anode electrode and a cathode electrode that supply power to the light-emitting element 20.

(Light Emitting Element)
As shown in FIG. 2A, the light-emitting element 20 is an LED (light-emitting diode) having a semiconductor light-emitting functional layer 26 including an n-type semiconductor layer, a light-emitting layer, and a p-type semiconductor layer, a light-transmitting substrate 25 provided on the upper surface of the semiconductor light-emitting functional layer 26, and a first element electrode 27A and a second element electrode 27B provided on the lower surface of the semiconductor light-emitting functional layer 26. The semiconductor light-emitting functional layer 26 is a GaN-based compound semiconductor. It is also possible to use an AlInGaP-based or InGaAs-based compound semiconductor. The light-transmitting substrate 25 is a light-transmitting sapphire (Al ₂ O ₃ ) that transmits the light emitted from the semiconductor light-emitting functional layer 26. It is also possible to use gallium nitride (GaN), aluminum nitride (AlN), or silicon carbide (SiC) as the light-transmitting substrate 25.

The first element electrode 27A is connected to the p-type semiconductor of the semiconductor light-emitting functional layer 26, and the second element electrode 27B is connected to the n-type semiconductor of the semiconductor light-emitting functional layer 26. The first and second element electrodes 27A and 27B are joined to the first and second wiring electrodes 12A and 12B provided on the upper surface of the substrate 11 via a joining member 14. The light-emitting element 20 emits blue light from the light-emitting layer by passing electricity through the first mounting electrode 13A and the second mounting electrode 13B of the light-emitting device 10. The emitted light passes through the translucent substrate 25 and is emitted from the upper surface of the translucent substrate 25. The manner in which the first and second element electrodes 27A and 27B of the light-emitting element 20 are joined to the first and second wiring electrodes 12A and 12B of the substrate 11 in this manner is called flip-chip joining, and the light-emitting element 20 used for this purpose is called a flip-chip.

(Light conversion member)
The light conversion member 22 contains light conversion particles that absorb part or all of the light (primary light) emitted from the light emitting element 20 passing through it, convert the light to a longer wavelength than the wavelength of the light, and emit the converted light (secondary light). The light conversion member 22 is a ceramic phosphor containing alumina as a base material and cerium-activated yttrium aluminum garnet (YAG:Ce) phosphor particles as light conversion particles. The light emitted from the light conversion member 22 is white light in which blue primary light and green-yellow secondary light are mixed. In addition, the refractive index of alumina as a base material is 1.7, and the refractive index of YAG:Ce as light conversion particles is 1.84, which are different from each other, and the light conversion member 22 has a light scattering property. Therefore, white light of approximately the same hue is emitted from the upper surface and side surface of the light conversion member 22. When the light conversion member 22 that converts all of the blue primary light is used, only green-yellow secondary light is emitted.

As shown in FIG. 1B, the light conversion member 22 is adhered to the upper surface of the light emitting element 20 by a light-transmitting adhesive member 21. In addition, when viewed from above, the light conversion member 22 has a size that encompasses the light emitting element 20 and the adhesive member 21, and all of the outer surfaces of the light conversion member 22 protrude outward beyond the outer surfaces of the light emitting element 20 and the adhesive member 21. Note that the outer surface of the adhesive member 21 may protrude or recede slightly in a convex or concave manner from a surface extending from the outer surface of the light emitting element 20.

In this way, when viewed from above, all of the outer surfaces of the light conversion member 22 protrude outward beyond the outer surfaces of the light emitting element 20 and the adhesive member 21, so that the blue primary light and the greenish yellow secondary light can be emitted from the outer surfaces at approximately the same ratio as the upper surface of the light conversion member 22. In other words, the occurrence of color unevenness can be prevented.

In addition, the light conversion member 22 has a light receiving surface 22B (lower surface) that is wider than the emission surface (upper surface) of the light emitting element 20, and the entire circumference of the optical path from the emission surface of the light emitting element 20 through the adhesive member 21 to the light receiving surface 22B of the light conversion member 22 is covered with the first covering member 23, so that leakage of the emitted light (primary light) from the light emitting element 20 can be prevented. In other words, the emitted light from the light emitting element 20 is easily taken in by the light conversion member 22, and high light output can be obtained.

Moreover, the light converting member 22 is aligned so that its center coincides with the center of the light emitting element 20 in top view, and the outer surface of the light converting member 22 protrudes by a protrusion length PO from the outer surface of the light emitting element 20. Here, the protrusion length PO is 1/2 of the value obtained by subtracting the width CS of the light emitting element 20 in top view from the width PS of the light converting member 22 in top view (i.e., PO=(PS-CS)/2). Note that the protrusion length PO is preferably 3% to 7% of the width CS of the light emitting element 20.
For example, if the width CS of the light-emitting element 20 is 1.00 mm and the protrusion length PO of the light conversion member 22 is 5% of the width CS of the light-emitting element 20, the width PS of the light conversion member 22 is 1.10 mm and the protrusion length PO of the light conversion member 22 is 0.05 mm.

If the protruding length PO of the light conversion member 22 is large, the light emitted from the light emitting element 20 may not reach the outer periphery of the light conversion member 22, resulting in a noticeable decrease in brightness. Also, if the protruding length PO of the light conversion member 22 is small, the light emitted from the light emitting element 20 becomes dominant, resulting in a large color shift. Also, it becomes impossible to provide an adhesive surface between the light conversion member 22 and the first covering member 23.

As described above, it is preferable that the protrusion amount PO of the light conversion member 22 is (PS-CS)/2, that is, the protrusion amount PO of the two opposing side surfaces of the light conversion member 22 is equal. Furthermore, it is preferable that the protrusion amount PO of the four side surfaces of the light conversion member 22 is equal. However, this is not limited, and the protrusion amount PO of each side surface may be different from each other. Specifically, the center misalignment between the light conversion member 22 and the light emitting element 20 is not a problem as long as the protrusion length PO is within the above-mentioned range.

The light conversion member 22 is rectangular when viewed from above, and both of its upper surface 22A and light receiving surface 22B (lower surface) are substantially flat, and the opposing surfaces are formed substantially parallel to each other, so that the light conversion member 22 is formed in a plate shape as a whole. In addition, when observed microscopically, the surfaces of the upper surface 22A and the light receiving surface 22B have fine irregularities resulting from the alumina base material and the particles of the YAG:Ce light conversion particles. The light conversion member 22 is not limited to a rectangular plate shape having a flat surface, but can also have an uneven structure obtained by processing or a smooth surface property obtained by polishing or the like. In addition, a translucent protective film may be formed on the upper surface 22A and/or the outer surface. For example, there are a fluororesin thin film that repels dirt, a weather-resistant glass thin film, a dielectric multilayer film that controls the directional characteristics, and the like.

The base material of the light conversion member 22 can be a translucent ceramic or glass inorganic material, a translucent resin material, or the like. In addition, the light conversion particles can be cerium-activated yttrium aluminum garnet (YAG:Ce) phosphor, cerium-activated lutetium aluminum garnet (LuAG:Ce) phosphor, europium and/or cerium-activated orthosilicate ((Ba, Sr, Ca) SiO4:Eu, Ce) phosphor, cerium-activated terbium aluminum garnet (TAG:Ce), europium-activated α-sialon phosphor (α-SiAlON:Eu), europium-activated β-sialon phosphor (β-SiAlON:Eu), manganese-activated potassium potassium fluorosilicate (KFS:Mn), or the like. Different types of light conversion particles can be appropriately selected and used depending on the wavelength of the excitation light, the desired color tone, and the like. In addition, when multiple light-emitting elements 20 are mounted on one light-emitting device 10, a light conversion member 22 containing the same and/or different light conversion particles can be used for each light-emitting element 20.

The light conversion member 22 may be formed from a ceramic sintered body, a glass molded body, or a resin molded body containing light conversion particles. For example, a ceramic sintered body in which alumina is mixed with a YAG:Ce phosphor, a glass molded body in which a β-sialon phosphor is mixed with glass such as soda glass, borosilicate glass, or night glass containing a nitrogen component, or a resin molded body in which an orthosilicate phosphor is mixed with a silicone resin can be used.

If the light scattering property of the light conversion member 22 is insufficient, the light scattering property can _be improved by adding light scattering particles such as titanium oxide (TiO2), silicon oxide ( _SiO2 ), zinc oxide (ZnO), alumina ( _Al2O3 ), etc. Alternatively, the light scattering property can be improved by including pores of a size that has a light scattering effect.

In the above embodiment, the case where the light conversion member 22 is provided has been described, but the present invention is not limited to this. For example, if it is desired that the emitted light of the light emitting device 10 is only the emitted light of the light emitting element 20 (if light conversion particles are not mixed into the light conversion member 22), it is also possible to add only light scattering particles to the light conversion member 22 as described above.

(First Covering Member)
1B, the first covering member 23 starts from the outer periphery of the surface 22B of the light converting member 22 facing the light emitting element 20, i.e., the side of the light receiving surface 22B (lower surface) of the light converting member 22, and extends outward from the light converting member 22 while exposing the side surface of the light converting member 22. The first covering member 23 also covers the upper surface (23D) of the substrate 11, the side surface (23C) of the light emitting element 20 and the adhesive member 21 mounted on the substrate 11, and also covers the light receiving surface 22B (lower surface) of the light converting member 22. In other words, the light emitting element 20 is embedded and sealed by the first covering member 23.

In addition, the exposed surface of the first covering member 23 consists of an extending surface 23A (upper surface) that extends outwardly at a downward incline from the outer peripheral edge of the lower surface of the light conversion member 22, and an outer surface 23B that extends vertically from the outer peripheral edge of the extending surface 23A toward the outer peripheral edge of the upper surface of the substrate 11.
In this embodiment, the extending surface 23A and the outer surface 23B are the surfaces of the light emitting device 10 .

In this embodiment, the extending surface 23A is a curved surface that curves concavely outward and downward from the lower end of the outer periphery of the light conversion member 22 in a side view, but the extending surface 23A may be a curved surface that curves convexly outward and downward, or may have a flat shape. In addition, the extending surface 23A and the outer surface 23B may be continuously connected.

In addition, it is preferable that the outward protrusion length TW from the outer peripheral edge of the lower surface 22B of the light converting member 22 satisfies PT≦TW≦PS. If the minimum value of the protrusion length TW is less than the thickness PT of the light converting member 22, the reflection efficiency of the light emitted from the side surface of the light converting member 22 decreases. In addition, if the protrusion length TW exceeds the width PS of the light converting member 22, the size of the light emitting device 10 becomes unnecessarily large compared to the light converting member 22.

The base material of the first covering member 23 is a translucent silicone resin. Translucent resin materials such as epoxy resin, acrylic resin, polycarbonate resin, and polystyrene resin can also be used.

The first covering member 23 contains titanium oxide (TiO ₂ ) particles having light reflectivity as a light reflecting material. Since the outer surface of the light converting member 22 is not covered by the first covering member 23, the emitted light from the outer surface of the light converting member 22 is reflected by the extending surface 23A of the first covering member 23, thereby improving the light output in the on-axis direction.

For example, when the outer surface of the light converting member is covered with the first covering member, light loss occurs at the contact portion of the first covering member with the light converting member (for example, about 0.2 mm from the contact surface with the light converting member). Specifically, light bleeding occurs in the contact portion.
According to this embodiment, since the outer surface of the light converting member 22 is not covered with the first covering member 23, light can be extracted from the outer surface of the light converting member 22, preventing light loss and providing high light output. At the same time, the directional characteristics can be broadened.

More specifically, a comparison sample was created with the only difference being that the outer surface of the light conversion member was covered with a covering member up to the upper end, but with all other configurations being the same. The comparison sample and this embodiment were compared under the same conditions for light output (total luminous flux: lm) and half-value angle (directional angle at which light output is half of its maximum value). As a result, the light output of the comparison sample was 400 lm, and the half-value angle of the directional characteristics was 120°. In contrast, the light output of this embodiment was 420 lm, and the half-value angle of the directional characteristics was 125°. In other words, the light output of this embodiment was improved by 5% compared to the comparison sample. In addition, the half-value angle of the directional characteristics was expanded by 5°.

It is preferable that the TiO2 particles contained in the first coating member 23 have a particle size of 200 nm to 300 nm and a content of 8 to 60 wt %, for example. This is because the TiO2 particles having a particle size of 200 nm to 300 nm cause Mie scattering, resulting in excellent diffuse reflectivity.
In this embodiment, TiO2 particles are used as the light reflecting material, but zinc oxide (ZnO) particles, etc., can also be used in addition to TiO2 particles.

In addition, in the above, the extending surface 23A is described as extending outwardly from the outer peripheral edge of the lower surface 22B of the light converting member 22 at a downward incline, but this is not limited thereto. The extending surface 23A may extend outwardly from the outer peripheral edge of the lower surface 22B of the light converting member 22 at an upward incline. The extending surface 23A may also extend outwardly from the outer peripheral edge of the lower surface 22B of the light converting member 22 in parallel with the lower surface 22B of the light converting member 22. In other words, the extending surface 23A does not have to be inclined with respect to the lower surface 22B of the light converting member 22.

(Method of manufacturing a light-emitting device)
The method for manufacturing the light emitting device 10 of the first embodiment will be described in detail below with reference to a flowchart and the drawings. Fig. 3 is a flowchart showing the method for manufacturing the light emitting device 10. Figs. 4A to 4F are cross-sectional views showing each step. In each figure, the cutting lines for dividing the light emitting device 10 are indicated by dashed lines.

(S1) Preparation A glass epoxy substrate 11 having first and second wiring electrodes 12A, 12B, first and second through electrodes 28A, 28B, and first and second mounting electrodes 13A and 13B is prepared (FIG. 4A).
First and second wiring electrodes 12A and 12B are provided on the upper surface of the glass epoxy substrate 11. The glass epoxy substrate 11 also has first and second through electrodes 28A and 28B electrically connected to the first and second wiring electrodes 12A and 12B, respectively. A first mounting electrode 13A and a second mounting electrode 13B are provided on the rear surface of the glass epoxy substrate 11, electrically connected to the first and second through electrodes 28A and 28B, respectively.

(S2) Element Mounting Step: Gold-tin (Au-Sn) solder paste is applied onto the first and second wiring electrodes 12A, 12B on which the light-emitting element 20 and the protective element are to be mounted as the bonding material 14. Next, the light-emitting element 20 and the protective element are placed on the gold-tin solder paste.
The gold-tin cream solder is heated to 300° C. in a reflow furnace to melt and solidify, and the light emitting element 20 and the protective element are mounted on the first and second wiring electrodes 12A, 12B (FIG. 4B).

(S3) Light conversion member bonding step Silicone resin, which is a light-transmitting adhesive that is the adhesive member 21, is applied to the light-emitting surface (upper surface) of the light-emitting element 20. Next, the light conversion member 22 is placed on the light-emitting element 20. The silicone resin is temporarily cured by heating at 180° C. for 30 minutes to bond the light conversion member 22 ( FIG. 4C ).

(S4) Frame Forming Process A frame 80 is formed from a low-temperature curing resin on the outermost periphery of the glass epoxy substrate 11. The resin is cured by heating at 150° C. for 10 minutes. The resin may be a photocurable resin (FIG. 4D).

(S5) First covering member formation process The inside of the frame 80 is filled with the first covering member 23 made of silicone resin mixed with titanium oxide particles up to a height where it contacts the lower end of the outer edge of the light conversion member 22. The silicone resin is then cured by heating at 150°C for 120 minutes. At this time, the adhesive member 21 is also fully cured. The volume of the silicone resin is reduced, and the portion that becomes the extension surface 23A is formed into a concave curved shape (FIG. 4E).

(S6) Singulation Step The light emitting device 10 is cut into individual pieces using a dicer. Through the above steps, the light emitting device 10 is manufactured (FIG. 4F).

According to the present invention, by forming a resin frame in the manufacturing process (S4), a separate member such as a case for filling the first covering member 23 is not required. Therefore, the manufacturing process can be simplified to manufacture the light emitting device 10.

As described above, according to the present invention, it is possible to provide the light emitting device 10 that can reduce the loss of light emitted from the light emitting element 20 and obtain high light output. In addition, the directional characteristics can be made wider.
In this embodiment, a flip chip with a light-transmitting substrate is used as the light-emitting element 20, but the light-emitting element to be used is not limited to this. For example, the light-emitting elements exemplified below can also be used.

2B shows a light-emitting element 30 which is a single-sided electrode chip with a support substrate. The light-emitting element 30 has first and second element electrodes 34A and 34B, a support substrate 33 provided on the first and second element electrodes 34A and 34B, a bonding layer 32 provided on the support substrate 33, and a semiconductor light-emitting functional layer 31 provided on the bonding layer 32, the semiconductor light-emitting functional layer 31 including a p-type semiconductor, an n-type semiconductor, and a light-emitting layer.
The support substrate 33 is mainly made of silicon (Si) or ceramic.
The first element electrode 34 A is connected to a p-type semiconductor of the semiconductor light emitting functional layer 31 , and the second element electrode 34 B is connected to an n-type semiconductor of the semiconductor light emitting functional layer 31 .

2C shows a light-emitting element 40, which is a double-sided electrode chip with a support substrate. The light-emitting element 40 has a support substrate 43, a bonding layer 42 provided on the support substrate 43, and a semiconductor light-emitting functional layer 41 provided on the bonding layer 42, the semiconductor light-emitting layer including a p-type semiconductor, an n-type semiconductor, and a light-emitting layer.
A first element electrode 44A is provided on the upper surface of the support substrate 43, and a second element electrode 44B is provided on the lower surface of the support substrate 43.

The support substrate 43 is mainly made of silicon or ceramic.
The first element electrode 44A is connected to a p-type semiconductor of the semiconductor light-emitting functional layer 41, and the second element electrode 44B is connected to an n-type semiconductor of the semiconductor light-emitting functional layer 41. As shown in Fig. 2D, the first element electrode 44A is wire-bonded by a wire 46 to a first wiring electrode 12A (not shown) on the upper surface of the substrate 11 via a gold bump. The element electrode 44B is joined to a second wiring electrode 12B (not shown) via a connection member 14.

Therefore, the adhesive member 21 contains a spacer 45 so that the wire 46 does not come into contact with the light conversion member 22. This allows the lower surface 22B of the light conversion member 22 to be spaced apart from the wire 46 connected to the first element electrode 44A of the light emitting element 40.

Specifically, the spacer 45 with a particle size of 70 μm ensures a separation distance of 70 μm between the lower surface 22B of the light conversion member 22 and the upper surface of the light emitting element 40, and even at the point where the wire 46 with a wire diameter of 30 μm is connected to the gold bump with a height of 20 μm, there is no interference with the lower surface 22B of the light conversion member 22. Note that the spacer 45 can be made of soft glass or resin.

[Modification 1 of the first embodiment]
Modification 1 of the first embodiment will be described below. Note that the description of the same configuration as that of the light emitting device 10 according to the first embodiment of the present invention will be omitted as appropriate.
As shown in FIG. 5A, the light emitting device 50 according to the first modified example of the first embodiment has a substrate 11 having an upper surface and a lower surface, a light emitting element 20 mounted on the upper surface of the substrate 11, a light conversion member 22 provided on the emission surface (upper surface) of the light emitting element 20, a first covering member 23, and a second covering member 24.

The second covering member 24 covers the outer side surface of the light conversion member 22 and the extending surface 23A of the first covering member 23. In detail, the second covering member 24 has an upper surface that extends outwardly from the outer periphery of the upper surface 22A of the light conversion member 22 at an inclination downward, an inner circumferential surface that covers the outer side surface of the light conversion member 22, an outer side surface that extends vertically from the upper surface of the second covering member 24 toward the outer periphery of the upper surface of the substrate 11, and a lower surface that covers the entire extending surface 23A of the first covering member 23.
In this case, the light conversion member 22 can be fixed by the second covering member 24, and the sealing thickness between the outer surface of the light emitting device 50 and the light emitting element 20 can be increased, improving weather resistance.

The second covering member 24 can be made of a translucent resin material such as translucent silicone resin, epoxy resin, acrylic resin, polycarbonate, polystyrene resin, etc., which has a refractive index (average refractive index) smaller than that of the light conversion member 22 and larger than the refractive index of the air layer.
Therefore, by changing the refractive index stepwise in the order of the light conversion member 22, the second covering member 24, and the air layer, the light extraction efficiency of the light emitted from the light conversion member 22 can be improved.

[Modification 2 of the first embodiment]
A second modification of the first embodiment will be described. In the second modification, as shown in Fig. 5B, the second covering member 24 is configured to cover the entire upper surface 22A of the light converting member 22. In this case, it is possible to improve the light extraction efficiency of the emitted light from the upper surface 22A of the light converting member 22, and to protect the upper surface 22A of the light converting member 22 and the outer side surface of the light converting member 22.

A diffusing material can be mixed into the second coating member 24. The inclusion of a diffusing material can improve the angle dependency of chromaticity (color separation). As the diffusing material, for example, alumina particles, titanium oxide particles, zinc oxide particles, etc., with a particle size larger than the particles in the Mie scattering region can be used. In addition, the particle size is preferably 3 to 50 μm.

Second Embodiment
A second embodiment will be described below, and a description of the same configuration as that of the light emitting device 10 according to the first embodiment of the present invention will be omitted as appropriate.
The light-emitting device 60 of the second embodiment has a substrate 11 having an upper surface and a lower surface, a plurality of light-emitting elements 20 mounted on the upper surface of the substrate 11, a light conversion member 22 provided on the emission surface (upper surface) of the light-emitting element 20, and a first covering member 23.

As shown in FIG. 6B, the light emitting device 60 has four light emitting elements 20, which are arranged in a matrix of two rows and two columns at a distance from each other.
The overall virtual outer periphery of the four light-emitting elements 20 (a virtual line connecting the outer sides of the light-emitting elements 20) is rectangular, and the outer periphery of the light converting member 22 is also rectangular and equidistant from the virtual outer periphery of the four light-emitting elements 20. Therefore, efficient and uniform light conversion can be performed.

The distance between the light emitting elements 20 is preferably 1 to 2 times the protrusion length PO of the light converting member 22 .
If the separation distance between the light emitting elements 20 is more than twice as long, the light output of the light converting member 22 at the portions not reached by the light emitted from the light emitting elements 20 is attenuated, causing uneven brightness.

The four light emitting elements 20 are connected in series by the first and second wiring electrodes 12A and 12B and the first relay wiring electrode 12C, the second relay wiring electrode 12D, and the third relay wiring electrode 12E. Therefore, the same current can be passed through the four light emitting elements 20.
Moreover, the protective element 90 is located at the center of the arrangement of the four light-emitting elements 20 when viewed from above. Moreover, the protective element 90 is connected to the first wiring electrode 12A and the second wiring electrode 12B that extend to the positions of the four light-emitting elements 20. This arrangement can prevent loss of optical output.

In this embodiment, the plurality of light emitting elements 20 are connected in series by the first and second wiring electrodes 12A, 12B, but may be connected in parallel.
In addition, in the present embodiment, the number of the light-emitting elements 20 is four, but the number may be two, three, or five or more. That is, the light-emitting elements 20 can be arranged in one row and two columns, one row and three columns, one row and four columns, ..., m rows and n columns (m and n are integers) so that the light conversion member 22 is rectangular.

As shown in Figures 6A, 6B, and 6C, in top view, the light conversion member 22 is sized and positioned to include the four light emitting elements 20 that are placed at a predetermined distance apart. In other words, the light conversion member 22 protrudes outward by a protrusion length PO beyond the virtual outer periphery of the entire plurality of light emitting elements 20. The plurality of light emitting elements 20 are also placed at a distance of 1 to 2 times the protrusion length PO.

Therefore, the light conversion member 22 has a light receiving surface 22B (lower surface) that is wider than the emission surfaces (upper surfaces) of all the light emitting elements 20, and the periphery of the optical path from the emission surfaces of the light emitting elements 20 to the light receiving surface 22B of the light conversion member 22 is covered by the first covering member 23, thereby preventing leakage of the emitted light from the light emitting elements 20.
In other words, the light emitted from the light emitting element 20 can be easily taken into the light converting member 22, and high light output can be obtained. In addition, the light distribution characteristic can be made wider.

It is preferable that the emission surfaces (top surfaces) of the multiple light-emitting elements 20 are at the same height from the substrate 11. However, even if there is variation in the height of the emission surfaces of the multiple light-emitting elements 20 from the substrate 11, the variation in the light output emitted from the light-emitting device 50 can be suppressed by using the above-mentioned structure, in addition to the structure in which the translucent adhesive member 21 and the side surface of the adhesive member 21 are covered with the first covering member 23.

As explained in detail above, it is possible to provide a semiconductor light-emitting device that reduces the loss of light emitted from the light-emitting element and provides high light output.

10 Light emitting device 11 Substrate 12 Wiring 12A First wiring electrode 12B Second wiring electrode 13 Mounting electrode 13A First mounting electrode 13B Second mounting electrode 14 Joint member 20 Light emitting element 21 Adhesive member 22 Light conversion member 23 First covering member 24 Second covering member 25 Translucent substrate 26 Semiconductor light emitting functional layer 27A First element electrode 27B Second element electrode 28A First through electrode 28B Second through electrode 30 Light emitting element 31 Semiconductor light emitting functional layer 32 Joint layer 33 Support substrate 34A First element electrode 34B Second element electrode 40 Light emitting element 41 Semiconductor light emitting functional layer 42 Joint layer 43 Support substrate 44A First element electrode 44B Second element electrode 45 Spacer 46 Wire 50 Light emitting device 60 Light emitting device 70 Light emitting device 80 Frame 90 Protective element

Claims (8)

A substrate having two opposing main surfaces;
a semiconductor light emitting element disposed on an upper surface, which is one of the main surfaces of the substrate;
a light conversion member disposed on the semiconductor light emitting element;
a first covering member that covers a surface of the light conversion member facing the semiconductor light emitting element and an upper surface of the substrate and embeds the semiconductor light emitting element;
the first covering member extends outward from an outer periphery of a surface of the light converting member facing the semiconductor light emitting element while exposing a side surface of the light converting member,
the substrate includes the light converting member and protrudes outward beyond an outer surface of the light converting member when viewed from above;
The light conversion member includes the semiconductor light emitting element and protrudes outward beyond an outer surface of the semiconductor light emitting element when viewed from above. The light conversion member has light conversion particles,
The semiconductor light emitting device according to claim 1 , wherein the light converting member has a light scattering property for scattering the light emitted from the semiconductor light emitting element and the light emitted from the light converting particles. The semiconductor light-emitting device according to claim 1, wherein the first covering member has optical reflectivity that reflects light emitted from the semiconductor light-emitting element and the light conversion member. The semiconductor light-emitting device according to claim 3, wherein the first covering member contains light-reflecting particles that reflect the light emitted from the semiconductor light-emitting element and the light emitted from the light conversion particles contained in the light conversion member. The semiconductor light-emitting device according to claim 1 or 4, further comprising an adhesive member between the semiconductor light-emitting element and the light conversion member, the adhesive member being arranged so that light emitted from the upper surface of the semiconductor light-emitting element is incident on the lower surface of the light conversion member. The semiconductor light-emitting device according to claim 5, wherein the side surface of the adhesive member is covered by the first covering member. a second light-transmitting covering member that covers at least a side surface of the light converting member and an upper surface of the first covering member;
The semiconductor light emitting device according to claim 1 , wherein the second covering member has a refractive index larger than that of an air layer and smaller than that of the light converting member. A plurality of the semiconductor light emitting elements are provided,
The semiconductor light emitting device according to claim 1 , wherein the light conversion member includes all of the semiconductor light emitting elements and protrudes outward beyond the outer edges of the semiconductor light emitting elements when viewed from above.

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