JP7594187B2 - Light emitting device and method for manufacturing the same - Google Patents

Description

This disclosure relates to a light-emitting device and a method for manufacturing the same.

Light-emitting devices that use light-emitting elements such as light-emitting diodes (LEDs) and laser diodes (LDs) are light sources with high conversion efficiency, and are used in a wide range of fields, such as light-emitting devices for general lighting such as vehicle-mounted lighting in automobiles and interior lighting, backlight light sources for image display devices that use liquid crystal, illumination, traffic signal lights, and light source devices for projectors.

Light-emitting devices using LEDs are known to use light-emitting elements mounted on a substrate with wiring. In addition, development is underway on packages that are roughly the same size as the light-emitting elements, known as CSPs (chip scale packages), and surface-type light-emitting devices that mount multiple light-emitting elements at high density.

The light emitting device includes a light emitting element arranged on a substrate, a wavelength conversion member that converts the wavelength of the light emitted from the light emitting element, and a reflective member for reflecting the light emitted from the light emitting element. The reflective member is a resin composition containing a resin and an additive such as titanium oxide that reflects light. For example, Patent Document 1 discloses a light emitting device in which a wavelength conversion member is arranged at a distance from an LED. Patent Document 1 discloses a reflective member composition that contains a heat-resistant fluororesin and titanium oxide that has been surface-treated with a silicone oil compound as a reflective member that is arranged near the light emitting element to allow the light emitted from the light emitting element to reach the wavelength conversion member arranged at a distance from the light emitting element.

JP 2014-185294 A

One aspect of the present invention aims to provide a light-emitting device and a manufacturing method thereof that can suppress the occurrence of breakage or cracks in the resin member.

The light emitting device according to the first aspect of the present invention comprises a substrate, a light emitting element disposed on the substrate and having an upper surface as a light extraction surface, a wavelength conversion member containing a phosphor disposed on the upper surface of the light emitting element, and an outer resin member disposed on the side of the wavelength conversion member, the outer resin member containing a silicone resin and titanium oxide surface-treated with silicone oil.

The method for manufacturing a light-emitting device according to the second aspect of the present invention includes the steps of arranging a plurality of light-emitting elements, whose upper surfaces are light extraction surfaces, vertically and horizontally on an aggregate substrate, arranging a plurality of wavelength conversion members containing a phosphor on the upper surfaces of the light-emitting elements, arranging a composition for an outer resin member on each side of the plurality of wavelength conversion members, curing the composition for the outer resin member to form an outer resin member, and cutting the outer resin member and the aggregate substrate between adjacent light-emitting elements, where the composition for the outer resin member contains a silicone resin and titanium oxide surface-treated with silicone oil.

According to one aspect of the present invention, it is possible to provide a light emitting device and a manufacturing method thereof that can suppress the occurrence of breakage or cracks in the resin member.

1 is a schematic cross-sectional view of a light emitting device according to an embodiment. 1 is a schematic plan view of a light emitting device according to an embodiment. 1 is a flowchart showing an example of a method for manufacturing a light emitting device. 1 is a flowchart showing an example of a method for manufacturing a light emitting device. 5A to 5C are schematic cross-sectional views showing an example of a process for producing a light emitting device. 5A to 5C are schematic cross-sectional views showing an example of a process for producing a light emitting device. 5A to 5C are schematic cross-sectional views showing an example of a process for producing a light emitting device. 5A to 5C are schematic cross-sectional views showing an example of a process for producing a light emitting device. 1A to 1C are schematic plan views showing an example of a process for producing a light emitting device. 1 is a flowchart showing an example of a method for manufacturing a light emitting device. 5A to 5C are schematic cross-sectional views showing an example of a process for producing a light emitting device. 5A to 5C are schematic cross-sectional views showing an example of a process for producing a light emitting device. 5A to 5C are schematic cross-sectional views showing an example of a process for producing a light emitting device. 5A to 5C are schematic cross-sectional views showing an example of a process for producing a light emitting device. 5A to 5C are schematic cross-sectional views showing an example of a process for producing a light emitting device. 5A to 5C are schematic cross-sectional views showing an example of a process for producing a light emitting device. 1A to 1C are schematic plan views showing an example of a process for producing a light emitting device.

For example, since the CSP has a size almost equal to that of the light-emitting element, the amount of resin material molding the periphery of the light-emitting element and the wavelength conversion member is small, and therefore when the light-emitting element is energized, cracks may easily occur in the resin material formed around the light-emitting element and the wavelength conversion member due to the influence of heat generated when energized and moisture absorption due to the external environment. When the light-emitting element is energized, heat is emitted from the light-emitting element together with the light. In addition, heat is also emitted from the wavelength conversion member arranged on the light extraction surface on the upper surface of the light-emitting element together with the wavelength-converted light. The outer resin member arranged around the wavelength conversion member has a reduced adhesion between the wavelength conversion member and the outer resin member due to the repeated heat generated from the light-emitting element and the wavelength conversion member by energization and the cooling of the light-emitting element and the wavelength conversion member by stopping the energization. In addition, since the outer resin member is exposed to the external environment, it is also easily affected by humidity and the like. In particular, in the case of a small light-emitting device that is almost the same size as the light-emitting element, such as a CSP, the width of the outer resin member provided around the light-emitting element and the wavelength conversion member becomes narrow, and the amount of the outer resin member decreases according to the narrow width. As a result, the outer resin member is more likely to break or crack. In particular, when the adhesion between the wavelength conversion member and the outer resin member decreases and the outer resin member peels off from the wavelength conversion member, this peeled portion becomes the starting point for further breakage or cracks.
The resin composition for the reflective member disclosed in Patent Document 1 contains a fluororesin that is solid at room temperature, and therefore, in order to arrange it in a small area, it is necessary to heat the fluororesin to a melting point or higher to melt it. Therefore, by heating the fluororesin to a melting point or higher, gas containing fluorine as the main component is released, which makes the manufacturing equipment susceptible to corrosion, and the cost of countermeasures becomes high, which increases the cost of the light-emitting device.

On the other hand, in order to suppress the influence of repeated heating and cooling from the light emitting element and the wavelength conversion member, it is conceivable to make the outer resin member softer, for example. However, when the outer resin member is softened, its adhesiveness increases, which may make it difficult to transport or pack it, resulting in poor mass productivity.
In order to soften the outer resin member and suppress the effects of the external environment, it is conceivable to add, for example, a liquid light stabilizer of a hindered amine type to the outer resin member. However, since the hindered amine type light stabilizer is basic, there are cases in which the hardening of the outer resin member is inhibited.

It is also possible to form a softer outer resin member using a resin with a low Shore A hardness, for example, a Shore A hardness of less than 30. However, with such a resin, the outer resin member remains soft and sticky even after it is formed, which may make it difficult to transport and package, resulting in poor mass production.

Therefore, by using the outer resin member according to this embodiment, it is possible to improve the adhesion between the wavelength conversion member and the outer resin member without softening the outer resin member, thereby suppressing breakage or cracks in the outer resin member.

The light-emitting device and the manufacturing method thereof according to the present invention will be described below based on the embodiments. However, the embodiments shown below are merely examples for embodying the technical idea of the present invention, and the present invention is not limited to the light-emitting device and the manufacturing method thereof. The relationship between the color name and the chromaticity coordinate, and the relationship between the wavelength range of light and the color name of monochromatic light are in accordance with JIS Z8110. In addition, in this specification, the terms "sheet", "film", "layer", and the like are not distinguished from each other based only on the difference in the name. Therefore, for example, "film" is used to mean a member that can also be called a sheet, and "sheet" is used to mean a member that can also be called a film.
In this specification, the terms "upper" and "lower" are also used to refer to the side from which light is extracted and the opposite side in a light-emitting device. For example, "upper" means the direction in which light is extracted, and "lower" means the opposite direction. Furthermore, "upper surface" means the surface on the side from which light is extracted, and "lower surface" means the surface on the opposite side. Furthermore, "side surface" means the surface perpendicular to the upper or lower surface.

The light emitting device will be described with reference to the drawings. FIG. 1 is a schematic cross-sectional view of a light emitting device according to an embodiment. FIG. 2 is a schematic plan view of a light emitting device according to an embodiment. However, for convenience of explanation, the size, thickness, etc. of the light emitting device and each component are merely exemplary and are exaggerated. Also, for convenience of the explanation below, the semiconductor element and inner resin member are also illustrated, but it is also possible to adopt a form that does not use a semiconductor element and inner resin member, as shown in FIG. 4D.

Light-emitting device The light-emitting device 100 includes a substrate 20, a light-emitting element 10 arranged on the substrate 20 and having an upper surface 10a as a light extraction surface, a wavelength conversion member 50 containing a phosphor arranged on the upper surface 10a of the light-emitting element 10, and an outer resin member 40 arranged on the side of the wavelength conversion member 50. The outer resin member 40 includes a silicone resin and titanium oxide surface-treated with silicone oil. The light-emitting element 10 is flip-chip mounted on the substrate 20 via a conductive member 60 called a bump. The light-emitting device 100 includes a semiconductor element 70 on the substrate 20, which is separate from the light-emitting element 10. The semiconductor element 70 is also flip-chip mounted on the substrate 20 via the conductive member 60. The light-emitting device 100 includes an inner resin member 30 arranged around the light-emitting element 10. In a plan view, the area of the wavelength conversion member 50 is preferably larger than the area of the upper surface 10a of the light-emitting element 10. The upper surface 50a of the wavelength conversion member 50 becomes the light extraction surface of the light-emitting device 100. The wavelength conversion member 50 is preferably bonded to the upper surface 10a of the light emitting element 10 via the light guide member 80. The light guide member 80 continuously covers the side surface and the upper surface 10a of the light emitting element 10. The inner resin member 30 is disposed on the side of the light emitting element 10, contacts at least a part of the light guide member 80, and covers at least a part of the side surface 70b of the semiconductor element 70. The outer resin member 40 is disposed on the side of the wavelength conversion member 50, on the inner resin member 30, and on the semiconductor element 70, and embeds the semiconductor element 70. The thickness T of the outer resin member 40 refers to the thickness in the vertical direction relative to the substrate 20. When the inner resin member 30 is provided, the thickness T refers to the difference obtained by subtracting the height of the inner resin member 30 from the height of the outer resin member 40 in the vertical direction relative to the substrate 20. The substrate 20 may be a piece that has been individually cut in advance, or may be a piece that has been individually cut from the collective substrate 20a in a manufacturing method described later, and the same reference numerals are used.

In the light emitting device 100, the outer resin member 40 constitutes the outer shape of the light emitting device 100. When the upper surface 50a of the wavelength conversion member 50 is rectangular, if the size of the shortest side of the upper surface 50a of the wavelength conversion member 50 is 1, the narrowest width W from the end of the upper surface 50a of the wavelength conversion member 50 to the end of the outer shape of the light emitting device 100 constituted by the outer resin member 40 can be in the range of 0.10 mm to 0.30 mm.

Outer resin member The outer resin member is disposed to the side of the wavelength conversion member, and the upper surface of the outer resin member is preferably flush with the upper surface of the wavelength conversion member. In other words, it is preferable to dispose the outer resin member so that the height of at least a part of the upper surface of the outer resin member is the same as the light extraction surface of the wavelength conversion member. This makes it possible to provide a light emitting device having a substantially rectangular parallelepiped shape.
In addition, a part of the upper surface of the outer resin member may have a "sink". For example, the part of the outer resin member that is in contact with the side surface of the wavelength conversion member may be at the same height as the light extraction surface of the wavelength conversion member, and the part that is not in contact with the side surface of the wavelength conversion member may be at a lower height than the light extraction surface of the wavelength conversion member. This is because a depression called a "sink" may occur on the upper surface of the outer resin member as the resin constituting the outer resin member cures and shrinks.

The outer resin member includes a silicone resin and titanium oxide surface-treated with silicone oil. When moisture adheres to the surface of the titanium oxide contained in the outer resin member, the photocatalytic action of the titanium oxide increases, accelerating the photodegradation of the silicone resin contained in the outer resin member, causing some of the silicone resin components to decompose and volatilize or become brittle. When the silicone resin components contained in the outer resin member volatilize or become brittle, the outer resin member is more likely to crack or break. Titanium oxide surface-treated with silicone oil has less moisture present on the titanium oxide surface. Therefore, the outer resin member containing titanium oxide surface-treated with silicone oil and silicone resin is less susceptible to photodegradation and the decomposition of the resin components is suppressed, making it less likely to become brittle, and as a result, the occurrence of cracks or breaks in the outer resin member can be suppressed.

In order to prevent breakage or cracking of the outer resin member, for example, it is possible to make the outer resin member softer. In order to soften the outer resin member and prevent influences from the external environment, for example, it is possible to add a liquid light stabilizer to the outer resin member. An example of a liquid light stabilizer is a hindered amine light stabilizer. However, when a hindered amine light stabilizer is added to the outer resin member, the curing of the outer resin member may be inhibited due to the basic light stabilizer. If curing is inhibited, the outer resin becomes soft and sticky, which may make it difficult to transport and package, and may result in poor mass production.

In order to form a softer outer resin member, it is also possible to form the outer resin member using a resin with a low Shore A hardness. However, when the outer resin member is formed using a resin with a low hardness, for example, a Shore A hardness of less than 30, the outer resin member remains soft and sticky even after it is formed, which may make it difficult to transport or package, and may result in poor mass productivity.

The outer resin member contains silicone resin and titanium oxide that has been surface-treated with silicone oil, which helps prevent the outer resin member from breaking or cracking without making it softer.

The titanium oxide may be rutile type titanium oxide, anatase type titanium oxide, or brookite type titanium oxide, but rutile type titanium oxide is preferable because it has a stable crystal structure and high reflectance. The average particle size of the titanium oxide may be in the range of 0.1 μm to 1 μm, or in the range of 0.2 μm to 0.8 μm. The titanium oxide preferably contains titanium dioxide as the main component.

The silicone oil is preferably at least one selected from the group consisting of dimethyl silicone oil, methyl phenyl silicone oil, and methyl hydrogen silicone oil. Two or more types of silicone oil may be used in combination.

Titanium oxide is preferably surface-treated by dry-mixing titanium oxide with silicone oil and then heating. By dry-mixing titanium oxide with silicone oil and then heating, a strong coating is formed on the titanium oxide surface, and the moisture present on the titanium oxide surface can be reduced.

The titanium oxide surface-treated with silicone oil contained in the outer resin member is preferably in the range of 20 parts by mass to 80 parts by mass, or may be in the range of 25 parts by mass to 75 parts by mass, or may be in the range of 30 parts by mass to 70 parts by mass, relative to 100 parts by mass of silicone resin. By surface-treating the titanium oxide, the amount of moisture adhering to the surface of the titanium oxide, which is the main cause of photodegradation of resin, is reduced, thereby suppressing the occurrence of cracks or breakage in the outer resin member.

The outer resin member may contain an inorganic material other than surface-treated titanium oxide, and the inorganic material other than surface-treated titanium oxide may be at least one selected from the group consisting of silicon dioxide, zirconium dioxide, yttria-stabilized zirconia, and aluminum oxide. When the outer resin member contains an inorganic material other than surface-treated titanium oxide, the total amount of the surface-treated titanium oxide and the inorganic material other than titanium oxide is preferably in the range of 20 parts by mass to 80 parts by mass, may be in the range of 25 parts by mass to 75 parts by mass, or may be in the range of 30 parts by mass to 70 parts by mass, relative to 100 parts by mass of silicone resin.

The silicone resin is preferably an addition reaction type silicone resin obtained from dimethylpolysiloxane and/or modified dimethylpolysiloxane containing at least two alkenyl groups bonded to silicon atoms in one molecule, and organohydrogenpolysiloxane containing at least two hydrogen atoms bonded to silicon atoms in one molecule. Addition reaction type silicone resins are desirable because they have little cure shrinkage and are less likely to damage other components of the light emitting device after curing.

The Shore A hardness of the silicone resin contained in the outer resin member is preferably in the range of 30 to 80, more preferably in the range of 40 to 80, even more preferably in the range of 55 to 80, and even more preferably in the range of 60 to 75. The Shore A hardness of the silicone resin contained in the outer resin member can be measured using a durometer type A in accordance with JIS K6253. If the silicone resin contained in the outer resin member has a Shore A hardness in the range of 30 to 80, the adhesiveness of the resin member is suppressed and the rubber properties (toughness, elongation) are excellent, so that if peeling from the wavelength conversion member is suppressed, it can flexibly expand or contract in response to heat dissipation or cooling from the wavelength conversion member, and cracks and breakage can be suppressed.

The thickness of the outer resin member is preferably within the range of 50 μm to 600 μm. The thickness of the outer resin member refers to the thickness in the direction perpendicular to the substrate. If the thickness of the outer resin member is 50 μm to 600 μm, the occurrence of breakage and cracks can be suppressed. The thickness of the outer resin member in the direction perpendicular to the substrate varies depending on the thickness of the semiconductor element and the thickness of the inner resin member, and the thickness varies depending on the part. If the thickness of each part of the outer resin member is within the range of 50 μm to 600 μm, the occurrence of breakage and cracks can be suppressed.

Substrate The material of the substrate is preferably an insulating material that is difficult for light from the light emitting element or external light to pass through. For example, ceramics such as alumina and aluminum nitride, and resins such as phenol resin, epoxy resin, polyimide resin, bismaleimide triazine resin (BT resin), and polyphthalamide (PPA) resin can be mentioned. When using a resin, an inorganic filler made of glass fiber, silicon oxide, titanium oxide, aluminum oxide, etc. may be mixed into the resin as necessary. By including an inorganic filler in the substrate, it is possible to improve the mechanical strength, reduce the thermal expansion coefficient, and improve the light reflectance.

Light-emitting element The light-emitting element may be a semiconductor light-emitting element such as a light-emitting diode (LED) or a laser diode (LD). A light-emitting element that emits light of any wavelength may be selected depending on the application. For example, a nitride semiconductor (In _x Al _y Ga _1-X-Y N, 0≦X, 0≦Y, X+Y≦1) capable of emitting a short wavelength that can efficiently excite the phosphor contained in the wavelength conversion member may be mentioned. Various emission wavelengths may be selected depending on the material of the semiconductor layer and its mixed crystal degree. A light-emitting element may be used in which a pair of electrodes, a p-electrode and an n-electrode, is formed on the lower surface opposite to the upper surface that serves as the light extraction surface. The light-emitting element preferably has an emission peak wavelength in the range of 380 nm to 500 nm, more preferably has an emission peak wavelength in the range of 390 nm to 495 nm, and even more preferably has an emission peak wavelength in the range of 400 nm to 490 nm. The light-emitting element is electrically connected to the substrate via a conductive member.

Wavelength conversion member The wavelength conversion member contains a phosphor. The wavelength conversion member may contain an inorganic material. The wavelength conversion member preferably contains a ceramic composite containing a phosphor and an inorganic material. The wavelength conversion member may be a single layer of a phosphor layer made of a ceramic composite containing a phosphor and an inorganic material, or may be a laminate of a phosphor layer made of a ceramic composite containing a phosphor and an inorganic material and a translucent layer made of at least one material selected from the group consisting of resin, glass, and inorganic substances. The ceramic composite containing a phosphor and an inorganic material may contain one type of first phosphor, or may contain another type of second phosphor having a different composition from the first phosphor. The first ceramic composite containing one type of first phosphor and an inorganic material may be the first phosphor layer, the second ceramic composite containing another type of second phosphor having a different composition from the first phosphor and an inorganic material may be the second phosphor layer, and a translucent layer not containing a phosphor may be laminated. The light-transmitting layer may be a plate-like body made of an inorganic oxide similar to the inorganic oxide contained in the ceramic composite, which will be described later.

The phosphor contained in the wavelength conversion member preferably includes a rare earth aluminate phosphor, and the inorganic material preferably includes an inorganic oxide. The phosphor may be a rare earth aluminate phosphor as the first phosphor. An example of the rare earth aluminate phosphor is an yttrium aluminum garnet phosphor (YAG phosphor). The YAG phosphor refers to a phosphor that has a garnet structure and is activated with at least one element selected from the group consisting of rare earth elements. Examples of rare earth aluminate phosphors include phosphors having a composition represented by Y ₃ (Al, Ga) ₅ O ₁₂ : Ce, Lu ₃ (Al, Ga) ₅ O ₁₂ : Ce, (Re _1-x Sm _x ) ₃ (Al _1-y Ga _y ) ₅ O ₁₂ : Ce (Re is at least one element selected from the group consisting of Y, Gd and La, and x and y satisfy 0≦x<1, 0≦y≦1, respectively). In this specification, in the composition formula showing the composition of the phosphor, a plurality of elements described separated by a comma (,) means that at least one element of these plurality of elements is contained in the composition formula, and two or more elements may be combined. In addition, in the formula showing the composition of the phosphor, the part before the colon (:) represents the elements constituting the host crystal and their molar ratio, and the part after the colon (:) represents an activating element. "Molar ratio" refers to the molar amount of an element in one mole of the phosphor composition.

The phosphor may include a phosphor having a phosphor with a different composition in addition to the rare earth aluminate phosphor. The phosphor may be a phosphor with a different composition from the rare earth aluminate phosphor as the second phosphor. Examples of phosphors having a different composition from rare earth aluminate phosphors include nitrogen-containing calcium aluminosilicate phosphors activated with europium and/or chromium (e.g., CaO-Al ₂ O ₃ -SiO ₂ :Eu,Cl), silicate phosphors activated with europium (e.g., (Sr,Ba) ₂ SiO ₄ :Eu), β-sialon phosphors (e.g., Si _6-z Al _z O _z N _8-z :Eu (0<z<4.2)), nitride phosphors (e.g., CaAlSiN ₃ :Eu (CASN phosphor), (Sr,Ca)AlSiN ₃ :Eu (SCASN phosphor)), fluoride phosphors activated with manganese (e.g., K ₂ SiF ₆ :Mn), sulfide phosphors, etc. The nitride phosphor is L _u M _v N _{((2/3)u + (4/3)v)} :R or L _u M _v O _w N _{((2/3)u + (4/3)v - (2/3)w).} :R (L is at least one Group 2 or 12 element selected from the group consisting of Be, Mg, Ca, Sr, Ba, and Zn, M is at least one Group 4 or 14 element selected from the group consisting of C, Si, Ge, Sn, Ti, Zr, and Hf, R is at least one rare earth element selected from the group consisting of Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, and Lu, and u, v, and w satisfy 0.5≦u≦3, 1.5≦v≦8, and 0<w≦3).

The inorganic oxide contained in the wavelength conversion member is preferably an inorganic oxide having translucency that transmits light from the light emitting element and light wavelength-converted by the phosphor. Examples of inorganic oxides include at least one inorganic oxide selected from the group consisting of SiO ₂ , Al ₂ O ₃ , ZrO ₂ , MgO, TiO ₂ , CeO ₂ , ZnO, SnO ₂ and Y ₂ O _3. In this specification, translucency means that 60% or more of the light emitted from the light emitting element and the light wavelength-converted by the phosphor are transmitted through the inorganic oxide. For example, the translucency may be 70% or more, 80% or more, or 90% or more of the light emitted from the light emitting element. When the phosphor contained in the ceramic composite is a rare earth aluminate phosphor, the inorganic material preferably contains Al ₂ O ₃ .

Semiconductor element The light emitting device preferably includes a semiconductor element on the substrate other than the light emitting element. The semiconductor element is preferably disposed adjacent to the light emitting element on the substrate. Examples of the semiconductor element include a transistor for controlling the light emitting element, a capacitor, and a Zener diode protection element that becomes conductive when a voltage equal to or higher than a specified voltage is applied. The protection element is a semiconductor element having a pair of electrodes, a p-electrode and an n-electrode, on one of the two opposing surfaces on the substrate side, similar to the light emitting element. The protection element is electrically connected to the substrate via a conductive member, similar to the light emitting element. The height of the semiconductor element connected to the substrate via a conductive member is preferably lower than the combined height of the light emitting element and the wavelength conversion member connected to the substrate via the conductive member. By completely burying the semiconductor element in the outer resin member, the upper surface of the outer resin member can be raised, thereby suppressing a recess (sink mark) that occurs on the upper surface of the outer resin member.

Conductive Member As the conductive member, a bump can be used, and as the material of the bump, Au or its alloy, eutectic solder (Au-Sn), Pb-Sn, lead-free solder, etc. The conductive member is not limited to a bump, and may be, for example, a conductive paste.

An inner resin member may be provided between the light-emitting element and the conductive member, between the semiconductor element and the conductive member, or between the conductive member and the conductive member. The inner resin member is a member for protecting the light-emitting element, the semiconductor element, the conductive member, etc. arranged on the substrate from dust, moisture, external forces, etc. Examples of materials for the inner resin member include silicone resin, epoxy resin, urea resin, etc. Furthermore, these resins may contain colorants, light diffusing materials, fillers, etc. as necessary.

Light guide member A light guide member is interposed between the light emitting element and the wavelength conversion member, and the light emitting element and the wavelength conversion member are bonded by the light guide member. The light guide member is preferably made of a material that can optically connect the light emitting element and the wavelength conversion member. The material constituting the light guide member may be at least one resin selected from the group consisting of epoxy resin, silicone resin, phenolic resin, and polyimide resin.

Inner resin member The light emitting device preferably includes an inner resin member around the light emitting element, up to the height of the upper surface of the light emitting element or the lower surface of the wavelength conversion member. By arranging the inner resin member around the side surface of the light emitting element, the light extraction efficiency is improved, and it is possible to provide a light emitting device with high brightness. The resin material constituting the inner resin member may include a resin material containing at least one selected from the group consisting of silicone resin, modified silicone resin, epoxy resin, and modified epoxy resin, and may be a hybrid resin containing two or more resins. The resin material constituting the inner resin member may include a silicone resin similar to that of the outer resin member. The inner resin member preferably contains a filler similar to that of the outer resin member. Specifically, the filler may include at least one selected from the group consisting of titanium oxide surface-treated with the above-mentioned silicone oil, titanium oxide not surface-treated with silicone oil, silicon dioxide, zirconium dioxide, yttria-stabilized zirconia, and aluminum oxide.

3. Manufacturing method of light-emitting device The manufacturing method of the light-emitting device will be described with reference to the drawings. Fig. 3 and Fig. 4 show a flow chart showing an example of the manufacturing method of the light-emitting device. Fig. 5A to Fig. 5D are schematic cross-sectional views showing an example of the steps of the manufacturing method of the light-emitting device according to the embodiment. Fig. 5E is a schematic plan view showing an example of the steps of the manufacturing method of the light-emitting device according to the embodiment. Each member shown in Fig. 5A to Fig. 5E can be the same as each member used in the above-mentioned light-emitting device.

The method for manufacturing a light emitting device includes step S101 of arranging multiple light emitting elements vertically and horizontally, step S103 of arranging multiple wavelength conversion members, step S106 of arranging a composition for the outer resin member, step S107 of forming the outer resin member, and step S108 of cutting the outer resin member and the assembly substrate. It may also include step S105 of preparing a composition for the outer resin member before step S106 of arranging the composition for the outer resin member. This will be described in detail below.

The method for manufacturing a light emitting device includes a step (S101) of arranging a plurality of light emitting elements vertically and horizontally on an aggregate substrate, with the upper surfaces of the light being the light extraction surfaces.
FIG. 5A shows a process of arranging a plurality of light emitting elements vertically and horizontally on the collective substrate 20a, with the upper surface being the light extraction surface. Here, arranging a plurality of light emitting elements 10 vertically and horizontally on the collective substrate 20a includes arranging in a matrix in the horizontal and vertical directions, and arranging in various two-dimensional patterns such as a checkered pattern or a lattice pattern. Here, the light emitting elements 10 arranged in a matrix are used as an example, and the horizontal direction is sometimes called the row direction and the vertical direction is sometimes called the column direction. A conductive pattern insulated and separated into positive and negative electrodes is formed on the collective substrate 20a, and the light emitting elements 10 are flip-chip mounted on the conductive pattern of the collective substrate 20a via a conductive member 60 called a bump. By flip-chip mounting, the light emitting elements 10 are mechanically and electrically connected to the collective substrate 20a. When mounting, the conductive member 60 may be provided on the collective substrate 20a side, or on the light emitting elements 10 or semiconductor element 70 side described later. An inner resin member may be filled between the light emitting elements 10 and the collective substrate 20a. This includes not only the case where the light emitting elements 10 are directly mounted on the collective substrate 20a, but also the case where the light emitting elements 10 are mounted on the collective substrate 20a via a submount substrate or the like.

The method for manufacturing a light emitting device includes a step (S103) of arranging a plurality of wavelength conversion members on the upper surfaces of a plurality of light emitting elements.
5B shows a process of arranging a plurality of wavelength conversion members 50 on the upper surfaces 10a of a plurality of light emitting elements 10 via a light guiding member 80. The light guiding member 80 bonds the light emitting elements 10 and the wavelength conversion members 50 to optically connect them. The light guiding member 80 can be arranged on the light emitting elements 10 by a known method such as a printing method, a spraying method, a molding method, or a potting method using a composition for a light guiding member, and the light emitting elements 10 and the wavelength conversion members 50 can be bonded to each other by arranging the wavelength conversion members 50 on the composition for a light guiding member and curing the composition for a light guiding member.

The method for producing a light emitting device may include a step (S105) of preparing a composition for an outer resin member prior to the step (S106) of disposing the composition for an outer resin member.
The process for preparing a composition for an outer resin member includes dry-mixing titanium oxide and silicone oil and heat-treating the mixture within a temperature range of 200°C or higher and 360°C or lower to obtain a surface-treated titanium oxide, and mixing the surface-treated titanium oxide with a silicone resin to obtain a composition for an outer resin member.
A dry mixer or the like can be used to mix titanium oxide and silicone oil. The heat treatment after dry mixing may be performed at a temperature in the range of 220° C. to 350° C., or in the range of 240° C. to 320° C. The heat treatment time may be 5 minutes to 120 minutes, 10 minutes to 90 minutes, or 15 minutes to 60 minutes.

In the process of preparing the composition for the outer resin member, the silicone oil is preferably mixed in the range of 0.5 parts by mass to 15 parts by mass to 100 parts by mass of titanium oxide, and may be mixed in the range of 1 part by mass to 12 parts by mass, or may be mixed in the range of 2 parts by mass to 10 parts by mass. By mixing the silicone oil in the range of 0.5 parts by mass to 15 parts by mass to 100 parts by mass of titanium oxide, the silicone oil adheres approximately uniformly to the surface of the titanium oxide, and by performing a heat treatment, the moisture or hydroxyl groups present on the surface of the titanium oxide can be reduced.

In the process of preparing the composition for the outer resin member, the surface-treated titanium oxide is preferably mixed in a range of 20 parts by mass to 80 parts by mass, or may be mixed in a range of 25 parts by mass to 75 parts by mass, or may be mixed in a range of 30 parts by mass to 70 parts by mass, relative to 100 parts by mass of the silicone resin. The silicone resin and the surface-treated titanium oxide can be mixed using various dispersing machines, mixers, kneaders, stirrers, etc., such as a three-roll mill, a rotation-revolution type mixer, a Raikai mixer, a twin-shaft kneader, a planetary mixer, etc.

The method for manufacturing a light emitting device includes a step (S106) of disposing a composition for an outer resin member on each side of a plurality of wavelength conversion members, and a step (S107) of curing the composition for the outer resin member to form an outer resin member.
5C shows a process of disposing the composition 40a for the outer resin member on the side of the wavelength conversion member 50, and a process of curing the composition 40a for the outer resin member to form the outer resin member 40. In FIG. 5C, the outer resin member 40 and the composition 40a for the outer resin member have different names depending on the curing, so two reference symbols are attached to the same member. The composition 40a for the outer resin member contains a silicone resin and titanium oxide surface-treated with silicone oil. The composition 40a for the outer resin member can use the above-mentioned composition for the outer resin member. By containing titanium oxide surface-treated with silicone oil in which the moisture on the surface, which is a cause of photodegradation, in the composition 40a for the outer resin member, photodegradation of the outer resin member 40 is suppressed, and cracks or breakage can be suppressed.

In the process of disposing the composition for the outer resin member 40a, the composition for the outer resin member 40a can be disposed by, for example, an injection molding method, a dripping method, a printing method, a molding method, a compression molding method, or the like. In the process of disposing the composition for the outer resin member 40a, it is preferable to dispose the composition for the outer resin member 40a by dripping it between the multiple wavelength conversion members 50. By disposing the composition for the outer resin member 40a by dripping it between the adjacent wavelength conversion members 50, the composition for the outer resin member 40a is positioned by the side surface 50b of the wavelength conversion member 50. For the purpose of positioning, it is not necessary to dispose, for example, a dam or the like. When disposing the composition for the outer resin member 40a by dripping it between the multiple wavelength conversion members 50, for example, a resin discharge device can be used. The composition for the outer resin member 40a can be disposed between the multiple wavelength conversion members 50 by moving the nozzle while dripping the composition for the outer resin member 40a from the nozzle at the tip of the resin discharge device filled with the composition for the outer resin member 40a.

The composition for the outer resin member 40a can be cured by heating to form the outer resin member 40. The heating temperature and time vary depending on the curing temperature of the composition for the outer resin member 40a, but for example, it can be cured by heating at a temperature of 50°C or higher and 200°C or lower for 1 hour to 20 hours. The composition for the outer resin member 40a may be heated in two stages, for example, first heated at a temperature of 50°C or higher and lower than 100°C for 1 hour to 10 hours, and then second heated at a temperature of 100°C or higher and 200°C or lower for 1 hour to 10 hours.

The method for manufacturing the light emitting device includes a step (S108) of cutting the outer resin member between adjacent light emitting elements and the collective substrate.
5D or 5E shows cutting lines 12 in the process of cutting the outer resin member 40 and the collective substrate 20a. The outer resin member 40 and the collective substrate 20a are both cut along the cutting lines 12 in at least one of the row direction and column direction in a plan view so as to include at least one light emitting element 10. This allows individual light emitting devices to be separated from a group of multiple light emitting devices, and the light emitting devices can be manufactured.

The manufacturing method of the light emitting device according to the different embodiments will be described with reference to the drawings. FIG. 6 shows a flow chart showing an example of the manufacturing method of the light emitting device. Also, FIGS. 7A to 7F are schematic cross-sectional views showing an example of the steps of the manufacturing method of the light emitting device according to the embodiment. FIG. 7G is a schematic plan view showing an example of the steps of the manufacturing method of the light emitting device according to the embodiment. Each of the members shown in FIGS. 7A to 7G can be the same as each of the members used in the light emitting device described above.

In a different embodiment, the method for manufacturing a light-emitting device includes step S201 of arranging a plurality of light-emitting elements vertically and horizontally, step S202 of arranging a plurality of semiconductor elements, step S203 of arranging a plurality of wavelength conversion members, step S204 of arranging a composition for an inner resin member, step S205 of preparing a composition for an outer resin member, step S206 of arranging a composition for an outer resin member, step S207 of forming an inner resin member and an outer resin member, and step S208 of cutting the outer resin member, the inner resin member, and the assembly substrate. However, since the method for manufacturing a light-emitting device according to a different embodiment is almost the same as the method for manufacturing a light-emitting device according to the above-mentioned embodiment except that a semiconductor element 70 and a composition 30a for an inner resin member are used, the description of steps S201, S203, S205, and S206 may be omitted.

The manufacturing method for the light-emitting device includes a step (S202) of arranging a plurality of light-emitting elements other than the light-emitting elements between adjacent light-emitting elements in either the horizontal or vertical direction of the light-emitting elements arranged vertically and horizontally, during the step of arranging the light-emitting elements, or before or after the step of arranging the plurality of light-emitting elements.
FIG. 7A shows a process of arranging a plurality of light emitting elements 10 vertically and horizontally on the collective substrate 20a. FIG. 7B shows a process of arranging a plurality of semiconductor elements 70 vertically and horizontally on the collective substrate 20a. FIG. 7C shows a process of arranging a plurality of wavelength conversion members 50 via a light guide member 80 on the upper surface 10a of a plurality of light emitting elements 10. In the process of arranging a plurality of light emitting elements 10 vertically and horizontally on the collective substrate 20a, or before and after the process of arranging a plurality of light emitting elements 10 vertically and horizontally, a plurality of semiconductor elements 70 other than the light emitting elements 10 are arranged between adjacent light emitting elements 10 in either the row direction or the row direction of the light emitting elements arranged vertically and horizontally. The semiconductor element 70 is flip-chip mounted on the conductive pattern of the collective substrate 20a via a conductive member 60 called a bump, similar to the light emitting element 10. An inner resin member may be filled between the semiconductor element 70 and the conductive member 60.

The method for manufacturing a light emitting device includes a step (S204) of arranging an inner resin member composition around the light emitting elements after the step of arranging a plurality of light emitting elements and before the step of arranging an outer resin member composition.
7D shows a process of arranging the inner resin member composition 30a around the light emitting element 10 after the process of arranging a plurality of light emitting elements 10 vertically and horizontally and before the process of arranging the outer resin member composition. In FIG. 7D and FIG. 7E, the inner resin member 30 and the inner resin member composition 30a have different names depending on the curing, so two reference symbols are given to the same member. In the process of arranging the inner resin member composition 30a, it is preferable to cover at least a part of the side surface of the semiconductor element 70 with the inner resin member composition 30a. The semiconductor element 70 may be arranged so that not only the side surface but also at least a part of the upper surface of the semiconductor element 70 is covered with the inner resin member composition 30a. By arranging the inner resin member 30 around the light emitting element 10 and the semiconductor element 70, the amount of light emitted from the light emitting element 10 that is absorbed by the semiconductor element 70 and the adjacent light emitting element 10 is reduced, and a high-output light emitting device can be provided. The composition for the inner resin member 30a can be arranged by, for example, an injection molding method, a dropping method, a printing method, a molding method, a compression molding method, or the like. In order to arrange the composition for the inner resin member 30a around the light emitting element 10 and the semiconductor element 70, it is preferable to arrange the composition for the inner resin member 30a by a dropping method. The composition for the inner resin member 30a is arranged around the light emitting element 10 and the semiconductor element 70, and then heated and cured. In addition, the composition for the inner resin member 30a may be arranged around the light emitting element 10 and the semiconductor element 70, heated to perform provisional curing, and further arranged on the outer resin member composition 40a, and then heated together with the composition for the outer resin member 40a to perform main curing. In addition, the composition for the inner resin member 30a may be arranged around the light emitting element 10 and the semiconductor element 70 ... curing.

The method for manufacturing the light emitting device includes a step of preparing a composition for an outer resin member (S205), a step of arranging the composition for the outer resin member on each side of a plurality of wavelength conversion members (S206), and a step of curing the composition for the inner resin member and the composition for the outer resin member to form the inner resin member and the outer resin member (S207).
7E shows a process of disposing the outer resin member composition 40a on each side of the plurality of wavelength conversion members 50, and curing the outer resin member composition 40a to form the outer resin member 40. In the process of disposing the outer resin member composition 40a, it is preferable to dispose the outer resin member composition 40a so as to cover the side surface 50b of the wavelength conversion member 50 and to cover the upper surface 70a of the plurality of semiconductor elements 70. The outer resin member composition 40a may be disposed so as to bury the semiconductor element 70. By disposing the outer resin member composition 40a so as to cover the upper surface 70a of the semiconductor element 70, the upper surface of the outer resin member composition 40a is raised, and a recess (sink mark) that occurs on the upper surface of the outer resin member 40 due to the cure shrinkage of the outer resin member composition 40a can be suppressed.

In the step of disposing the composition for the outer resin member 40a, it is preferable to dispose the composition for the outer resin member 40a on the surface of the composition for the inner resin member 30a. By disposing the composition for the outer resin member 40a on the surface of the composition for the inner resin member 30a, the inner resin member 30 after curing is protected by the outer resin member 40, and the inner resin member 30 can be protected from the influence of the external environment such as heat and humidity.
The inner resin member composition 30a and the outer resin member composition 40a can be cured by heating to form the inner resin member 30 and the outer resin member 40. The heating temperature and time vary depending on the curing temperature of the inner resin member composition 30a and the outer resin member composition 40a, but can be cured by heating for example at a temperature of 50°C or more and 200°C or less for 1 hour to 20 hours. The inner resin member composition 30a and the outer resin member composition 40a may be heated in two stages, for example, first heating at a temperature of 50°C or more and less than 100°C for 1 hour to 10 hours, and then second heating at a temperature of 100°C or more and 200°C or less for 1 hour to 10 hours.

The method for manufacturing the light emitting device includes a step (S208) of cutting the inner resin member, the outer resin member, and the collective substrate between adjacent light emitting elements.
7F or 7G shows a cutting line 12 in a process of cutting the outer resin member 40, the inner resin member 30, and the collective substrate 20a between adjacent light emitting elements 10. As shown in FIG. 7F or 7G, the outer resin member 40 and the inner resin member 30 arranged between the light emitting elements 10 in one of the row direction and the column direction and between the light emitting elements 10 and the semiconductor element 70 in the other of the row direction and the column direction are cut along the cutting line 12 so as to include at least one light emitting element 10 and one semiconductor element 70, together with the collective substrate 20a. By the process of cutting the outer resin member 40 and the collective substrate 20a, or the inner resin member 30, the outer resin member 40, and the collective substrate 20a, individual light emitting devices can be separated from a group of a plurality of light emitting devices, and light emitting devices can be manufactured.
Here, the embodiment including the semiconductor element 70 and the inner resin member 30 has been described, but either one of them may be omitted.

The present invention will be described in detail below with reference to examples. The present invention is not limited to these examples.

Example 1
As described in the above embodiment, the light emitting device according to Example 1 was manufactured by the same steps as in the manufacturing method of the light emitting device shown in Figures 1 and 2 and the light emitting device shown in Figures 7A to 7G. Descriptions of the same parts as in the above embodiment may be omitted.
A substrate having a conductive pattern formed on its surface was prepared. A flat aluminum nitride substrate was used as the substrate. The substrate was formed by firing an aluminum nitride plate having a thermal conductivity of 170 W/m·K. A conductive pattern was formed on the substrate using a metal material such as Cu, Ni, or Au to electrically connect to the light-emitting element. The substrate of one light-emitting device has a length and width of about 1.8 mm and about 1.45 mm, respectively, and a thickness of about 0.4 mm. The thickness of the conductive pattern is about 2 μm.

A plurality of light-emitting elements were arranged vertically and horizontally on the assembly substrate. A semiconductor element was arranged between the light-emitting element and the adjacent light-emitting element in either the row direction or the column direction of the multiple light-emitting elements arranged vertically and horizontally. The light-emitting element has a planar shape of approximately 1.0 mm square with a semiconductor layer stacked on a sapphire substrate, and a thickness of approximately 0.11 mm. The light-emitting element was flip-chip mounted on the conductive pattern using a conductive member made of Au, with the sapphire substrate being the light extraction surface (top surface). The semiconductor element had a planar shape of 0.4 mm x 0.3 mm rectangular and a thickness of approximately 0.14 mm. The semiconductor element was provided with bumps made of Au in advance and flip-chip mounted on the conductive pattern. The distance between the light-emitting element and the adjacent light-emitting element in the row direction was 0.75 mm, and the distance between the light-emitting element and the adjacent light-emitting element in the column direction was 0.38 mm, and the semiconductor element was arranged between the light-emitting element in the row direction with the larger distance and the adjacent light-emitting element.

Next, multiple wavelength conversion members were placed on multiple light emitting elements, and the wavelength conversion members were bonded to the sapphire substrate surface, which is the light extraction surface (upper surface) of the light emitting elements, using a light guide _{member. The wavelength conversion members were made of a ceramic composite containing a YAG phosphor having a composition represented by Y3(Al,Ga)5O12 : Ce} , which is a rare earth aluminate phosphor, and aluminum oxide. The wavelength conversion member had a planar shape of approximately 0.95 mm square and a thickness of approximately 0.2 mm.

Next, the composition for the inner resin member was arranged so as to cover the periphery of the light-emitting element and at least a part of the side surface of the semiconductor element. The composition for the inner resin member includes polydimethylsiloxane having at least two alkenyl groups bonded to silicon atoms in one molecule, organohydrogenpolysiloxane having at least two hydrogen atoms bonded to silicon atoms in one molecule, dimethylsilicone resin containing a hydrosilylation catalyst, and titanium oxide particles. The composition for the inner resin member was blended with 30 parts by mass of titanium oxide particles per 100 parts by mass of dimethylsilicone resin. The composition for the inner resin member was dripped and arranged around the plurality of light-emitting elements and the plurality of semiconductor elements.

Next, a composition for an outer resin member was prepared.
As the titanium oxide, 3 parts by mass of methyl hydrogen silicone oil was added to 100 parts by mass of rutile titanium dioxide (average particle size: 0.28 μm, see the description in the catalog), mixed for 2 minutes in a dry mixer, and heat-treated at 260° C. for 30 minutes to obtain titanium oxide surface-treated with silicone oil.
To 100 parts by mass of dimethyl silicone resin having a Shore A hardness of 60, 60 parts by mass of titanium oxide that had been surface-treated with silicone oil was added, and the mixture was mixed in a triple roll mill to prepare a composition for an outer resin member.

Next, the composition for the outer resin member was placed on the side of the wavelength conversion member. The composition for the outer resin member was dropped and placed between the multiple wavelength conversion members so as to cover the surface of the composition for the inner resin member, the upper surface of the semiconductor element, and the side surface of the wavelength conversion member.

Next, the substrate and other members that had undergone the above steps were placed in a heating furnace and first heated at 80°C for 2 hours, and then second heated at 150°C for 3 hours to cure the composition for the inner resin member and the composition for the outer resin member, forming the inner resin member and the outer resin member. The thickness T of the outer resin member was 350 μm.

Next, as shown in Figures 7F and 7G, the outer resin member, inner resin member, and assembly substrate arranged between the light-emitting elements in one of the row direction and column direction, and between the light-emitting elements and the semiconductor elements in the other of the row direction and column direction, were cut along the cutting lines so as to include at least one light-emitting element and one semiconductor element, and individual light-emitting devices were separated from the plurality of light-emitting device groups, thereby manufacturing the light-emitting device of Example 1. The narrowest width W from the end of the wavelength conversion member to the end of the outer shape of the light-emitting device constituted by the outer resin member of the obtained light-emitting device was in the range of 0.10 mm to 0.30 mm.

Comparative Example 1
The light-emitting device of Comparative Example 1 was manufactured in the same manner as in Example 1 using the same outer resin member composition as in Example 1, except that, as the composition for the outer resin member, 60 parts by mass of rutile-type titanium oxide (average particle size: 0.28 μm, see the description in the catalog) that had not been surface-treated with silicone oil was added to 100 parts by mass of the same dimethyl silicone resin as the dimethyl silicone resin used in Example 1.

Comparative Example 2
The light emitting device of Comparative Example 2 was manufactured in the same manner as in Example 1 using the same outer resin member composition as in Comparative Example 1, except that 0.6 parts by mass of 4-(3[(triethoxy)silyl]propoxy)-1,2,2,6,6-pentamethylpiperidine (CaS. No. 105918-62-5), a silane coupling agent containing a hindered amine-based light-stabilizing group, was further added as the outer resin member composition.

Comparative Example 3
The light emitting device of Comparative Example 3 was manufactured in the same manner as in Example 1 using the same outer resin member composition as in Comparative Example 1, except that a dimethyl silicone resin having a Shore A hardness of 28 measured by the method described below was used as the outer resin member composition.

The following evaluations were carried out for the Examples and Comparative Examples. The results are shown in Table 1.

Shore A Hardness The Shore A hardness of the silicone resin contained in the outer resin member was measured in accordance with JIS K6253 using a durometer type A (product name: GS-709G, manufactured by TECLOCK Corporation).

The elastic modulus of the outer resin member was measured under the following conditions using a dynamic microhardness tester (product name: DUH, manufactured by Shimadzu Corporation). The elastic modulus of the outer resin member of Comparative Example 1 was set as 100%, and the elastic modulus of each of the outer resin members of the Examples and Comparative Examples was expressed as a relative elastic modulus to the elastic modulus of the outer resin member of Comparative Example 1.
Measurement location: outer resin member of light-emitting device Indenter: 6 μm
Test force: 3 mN

Crack occurrence time of outer resin member Each light emitting device of the examples and comparative examples was continuously energized at 1.5 A in an atmosphere of 85°C and 85% relative humidity, and the time until a crack occurred from the light extraction surface (upper surface) of the wavelength conversion member to the end of the outer resin member was measured by visual observation. The time until the crack occurred in the outer resin member of Comparative Example 1 was set as 0 hours, and the time until the crack occurred in each outer resin member of the examples and comparative examples minus the time until the crack occurred in the outer resin member of Comparative Example 1 was expressed as the crack occurrence time.

It was confirmed that the outer resin member used in the light emitting device of Example 1 had a high relative elastic modulus of 146%, and that its hardness was not reduced compared to the outer resin member of Comparative Example 1. In addition, it was confirmed that the outer resin member used in the light emitting device of Example 1 took 500 hours longer for cracks to occur compared to the outer resin member of Comparative Example 1, and thus the occurrence of cracks was suppressed.

The outer resin member used in the light emitting device of Comparative Example 2 had a relative modulus of elasticity of 84%, which was lower than that of the outer resin member of Comparative Example 1. The time until cracks occurred was also 100 hours, which was shorter than that of the outer resin member used in the light emitting device of Example 1. It was presumed that the outer resin member used in the light emitting device of Comparative Example 2 had a lower relative modulus of elasticity because the added light stabilizer was basic, and the curing of the composition for the outer resin member was inhibited by the light stabilizer.

The outer resin member used in the light emitting device of Comparative Example 3 had a low Shore A hardness of 28, and because a soft silicone resin was used, the time to cracking was long at 500 hours, but the relative elasticity was low at 55%. The outer resin member of Comparative Example 3 was presumed to be soft and sticky, making it difficult to transport and package, and therefore poor for mass production.

Embodiments of the present disclosure can be used in CSPs and surface light-emitting devices. Light-emitting devices according to embodiments of the present disclosure can be used as light-emitting devices for general lighting, light-emitting devices for vehicles, and backlights for display devices of mobile devices, etc.

10: Light emitting element, 20: Substrate, 20a: Substrate assembly, 30: Inner resin member, 30a: Composition for inner resin member, 40: Outer resin member, 40a: Composition for outer resin member, 50: Wavelength conversion member, 60: Conductive member, 70: Semiconductor element, 80: Light guiding member, 100: Light emitting device.

Claims (18)

A substrate;
a light emitting element disposed on the substrate, the light emitting element having an upper surface as a light extraction surface;
A wavelength conversion member containing a phosphor and disposed on the upper surface of the light emitting element;
an outer resin member disposed on a side of the wavelength conversion member;
The light emitting device, wherein the outer resin member includes a silicone resin and titanium oxide that has been surface-treated with silicone oil. The light emitting device according to claim 1, further comprising an inner resin member arranged around the light emitting element. The light-emitting device according to claim 1 or 2, wherein the outer resin member contains 20 to 80 parts by mass of titanium oxide per 100 parts by mass of the silicone resin. The light-emitting device according to any one of claims 1 to 3, wherein the silicone oil is at least one selected from the group consisting of dimethyl silicone oil, methyl phenyl silicone oil, and methyl hydrogen silicone oil. The light-emitting device according to any one of claims 1 to 4, wherein the Shore A hardness of the silicone resin contained in the outer resin member is in the range of 30 to 80. The light-emitting device according to any one of claims 1 to 5, wherein the silicone resin is an addition reaction type silicone resin obtained from dimethylpolysiloxane and/or modified dimethylpolysiloxane containing at least two alkenyl groups bonded to silicon atoms in one molecule, and organohydrogenpolysiloxane containing at least two hydrogen atoms bonded to silicon atoms in one molecule. The light-emitting device according to any one of claims 1 to 6, further comprising a semiconductor element on the substrate, separate from the light-emitting element. The light emitting device according to any one of claims 1 to 7, wherein the wavelength conversion member includes a ceramic composite containing the phosphor and an inorganic material. The light emitting device according to claim 8, wherein the phosphor includes a rare earth aluminate phosphor, and the inorganic material is an inorganic oxide. The light-emitting device according to any one of claims 1 to 9, wherein the thickness of the outer resin member is in the range of 50 μm to 600 μm. A step of arranging a plurality of light emitting elements vertically and horizontally on an aggregate substrate, with the upper surface being a light extraction surface;
A step of disposing a plurality of wavelength conversion members containing a phosphor on an upper surface of the plurality of light emitting elements;
placing a composition for an outer resin member on each side of the plurality of wavelength conversion members;
curing the composition for the outer resin member to form an outer resin member;
cutting the outer resin member between adjacent light emitting elements and the assembly substrate;
The method for producing a light emitting device, wherein the composition for the outer resin member contains a silicone resin and titanium oxide that has been surface-treated with silicone oil. In the step of arranging the plurality of light-emitting elements vertically and horizontally, or before or after the step of arranging the plurality of light-emitting elements vertically and horizontally, a step of arranging a plurality of semiconductor elements other than the light-emitting elements between adjacent light-emitting elements in either the horizontal or vertical direction of the light-emitting elements arranged vertically and horizontally,
The method for manufacturing a light emitting device according to claim 11 , wherein in the step of arranging the composition for the outer resin member, the composition for the outer resin member is arranged so as to cover the side surfaces of the wavelength conversion member and to cover the upper surfaces of the plurality of semiconductor elements. The method for manufacturing a light-emitting device according to claim 11 or 12, further comprising the step of arranging an inner resin member composition around the light-emitting elements after the step of arranging the plurality of light-emitting elements vertically and horizontally and before the step of arranging the outer resin member composition. The method for manufacturing a light-emitting device according to claim 13, which quotes claim 12, in which at least a portion of the side surface of the semiconductor element is covered with the composition for the inner resin member in the step of placing the composition for the inner resin member. The method for manufacturing a light-emitting device according to claim 13 or 14, wherein in the step of placing the composition for the outer resin member, the composition for the outer resin member is placed on a surface of the composition for the inner resin member. The method for manufacturing a light emitting device according to any one of claims 11 to 15, wherein in the step of disposing the composition for the outer resin member, the composition for the outer resin member is dispensed between the adjacent wavelength conversion members. The method includes a step of preparing a composition for an outer resin member before the step of disposing the composition for an outer resin member,
In the step of preparing a composition for an outer resin member, titanium oxide and silicone oil are dry-mixed and the mixture is heat-treated at a temperature of 200° C. or more and 360° C. or less to obtain a surface-treated titanium oxide;
The method for producing a light emitting device according to claim 11 , further comprising: mixing the surface-treated titanium oxide with a silicone resin to obtain the outer resin member composition. The method for manufacturing a light-emitting device according to claim 17, wherein in the step of preparing the composition for the outer resin member, silicone oil is mixed in a range of 0.5 parts by mass to 15 parts by mass to 100 parts by mass of titanium oxide.

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