JP7177359B2 - light emitting device - Google Patents

Description

The present invention relates to light emitting devices.

2. Description of the Related Art A light-emitting device is known in which a reflective resin is provided on the top surface of a transparent resin that seals a light-emitting element, and light from the light-emitting element is emitted to the outside from the side surface of the transparent resin (for example, Patent Document 1). Such a light-emitting device can spread light easily in the horizontal direction, and can be used, for example, as a light source for a backlight.

JP 2013-115280 A JP 2013-115088 A JP 2013-118244 A JP 2013-258175 A

In recent years, backlights have become thinner and thinner, and a local dimming method, which adopts a direct type method and controls the brightness of the backlight in accordance with an image, is spreading. Therefore, there is a demand for a light-emitting device that can spread light efficiently in the lateral direction.

An embodiment of the present invention includes the following configurations.
A light-emitting element comprising: a semiconductor laminate having an electrode-formed surface, a light-emitting surface opposite to the electrode-formed surface, and a side surface between the electrode-formed surface and the light-emitting surface; and a pair of electrodes provided on the electrode-formed surface. a light-reflective covering member covering the side surface of the light emitting element; and an optical member arranged over the light emitting surface of the light emitting element and the upper surface of the covering member, wherein the optical member is arranged above the light emitting element. and a translucent portion disposed between the light reflecting portion and the covering member and constituting a part of the outer surface of the light emitting device.

As described above, the light from the light emitting device can be spread in the horizontal direction more efficiently.

1 is a schematic perspective view showing an example of a light emitting device according to Embodiment 1; FIG. FIG. 1B is a schematic cross-sectional view along the IB-IB cross section of FIG. 1A; 1 is a schematic bottom view showing an example of a light emitting device according to Embodiment 1; FIG. 1 is a schematic perspective view of an optical member showing an example of a light emitting device according to Embodiment 1. FIG. FIG. 5 is a schematic cross-sectional view showing an example of a light emitting device according to Embodiment 2; FIG. 5 is a schematic bottom view showing an example of a light emitting device according to Embodiment 2; FIG. 11 is a schematic cross-sectional view showing an example of a light emitting device according to Embodiment 3; FIG. 11 is a schematic cross-sectional view showing a modified example of the light emitting device according to Embodiment 3; FIG. 4 is a schematic cross-sectional view showing a modified example of the light emitting device according to Embodiments 1 to 3; FIG. 4 is a schematic cross-sectional view showing a modified example of the light emitting device according to Embodiments 1 to 3; FIG. 4 is a schematic cross-sectional view showing a modified example of the light emitting device according to Embodiments 1 to 3; FIG. 4 is a schematic cross-sectional view showing a modified example of the light emitting device according to Embodiments 1 to 3; FIG. 4 is a schematic cross-sectional view showing a modified example of the light emitting device according to Embodiments 1 to 3; FIG. 4 is a diagram showing a method of manufacturing a light emitting device according to Embodiments 1 to 3; FIG. 4 is a diagram showing a method of manufacturing a light emitting device according to Embodiments 1 to 3; FIG. 4 is a diagram showing a method of manufacturing a light emitting device according to Embodiments 1 to 3; FIG. 4 is a diagram showing a method of manufacturing a light emitting device according to Embodiments 1 to 3; FIG. 4 is a diagram showing a method of manufacturing a light emitting device according to Embodiments 1 to 3; FIG. 4 is a diagram showing a method of manufacturing a light emitting device according to Embodiments 1 to 3; FIG. 4 is a diagram showing a method of manufacturing a light emitting device according to Embodiments 1 to 3; FIG. 4 is a diagram showing a method of manufacturing a light emitting device according to Embodiments 1 to 3; FIG. 11 is a schematic cross-sectional view showing an example of a light emitting device according to Embodiment 4; FIG. 10 is a diagram showing a method for manufacturing a light emitting device according to Embodiment 4; FIG. 10 is a diagram showing a method for manufacturing a light emitting device according to Embodiment 4; FIG. 10 is a diagram showing a method for manufacturing a light emitting device according to Embodiment 4; FIG. 10 is a diagram showing a method for manufacturing a light emitting device according to Embodiment 4; FIG. 11 is a schematic cross-sectional view showing an example of a light emitting device according to Embodiment 5; FIG. 10 is a diagram showing a method for manufacturing a light emitting device according to Embodiment 5; FIG. 10 is a diagram showing a method for manufacturing a light emitting device according to Embodiment 5; FIG. 10 is a diagram showing a method for manufacturing a light emitting device according to Embodiment 5; FIG. 10 is a diagram showing a method for manufacturing a light emitting device according to Embodiment 5; FIG. 12 is a diagram showing a modification of the method for manufacturing the light emitting device according to Embodiment 5; FIG. 12 is a diagram showing a modification of the method for manufacturing the light emitting device according to Embodiment 5; FIG. 12 is a diagram showing a modification of the method for manufacturing the light emitting device according to Embodiment 5; FIG. 12 is a diagram showing a modification of the method for manufacturing the light emitting device according to Embodiment 5; FIG. 11 is a cross-sectional view of an example of a light emitting device according to Embodiment 6; FIG. 12 is a cross-sectional view of another example of the light emitting device according to Embodiment 6; FIG. 4 is a cross-sectional view of a modification of the light emitting device according to Embodiments 1 to 6;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail based on the drawings. In the following description, terms indicating specific directions and positions (for example, "upper", "lower", and other terms including those terms) are used as necessary. These terms are used to facilitate understanding of the invention with reference to the drawings, and the technical scope of the present invention is not limited by the meaning of these terms. Parts with the same reference numerals appearing in multiple drawings indicate the same parts or members. Regardless of before and after molding, solidification, hardening, and singulation, the same names are used for explanation. In other words, the same name will be used to describe a member whose state changes depending on the stage of the process, such as when it is liquid before molding, becomes solid after molding, and then divides the solid after molding to change its shape. do.

A light-emitting device according to an embodiment includes a light-emitting element, a covering member, and an optical member. The covering member is light reflective and is arranged to directly or indirectly cover the side surface of the light emitting element.
The optical member is a member arranged over the light emitting element and the covering member. The optical member has at least a two-layer structure including a light reflecting portion and a light transmitting portion arranged therebelow.

A light reflecting portion of the optical member is arranged above the light emitting element. As a result, light from the light emitting element is less likely to be emitted to the outside from above (directly above) the light emitting element. The light transmitting portion of the optical member is arranged between the light reflecting portion and the covering member. In other words, the translucent portion of the optical member forms part of the side surface of the light emitting device. Light from the light-emitting element propagates through the light-transmitting portion of the optical member and is emitted to the outside mainly from the side surface of the light-transmitting portion.

In this way, the light from the light emitting device according to the embodiment is emitted to the outside mainly from the translucent portion which is part of the side surface of the light emitting device. Furthermore, by using a limited portion of the side surface of the light emitting device instead of the entire side surface as the light emitting surface, the light density of the light emitted to the outside can be improved. As a result, the light from the light emitting element can be efficiently emitted sideways. For example, when the light-emitting device is arranged directly under the light guide plate as a light source for backlight, it is possible to irradiate light over a wider range.
Each embodiment will be described in detail below.

<Embodiment 1>
A light emitting device 100 according to Embodiment 1 is shown in FIGS. 1A to 1C. The light emitting device 100 has a substantially rectangular parallelepiped external shape. The shape of the lower surface 101 and the upper surface 102 of the light emitting device 100 is a quadrangle such as a square or a rectangle. Moreover, the shape of the side surface 103 of the light emitting device 100 is also substantially rectangular.
Of the side surfaces 103, at least two opposite side surfaces 103 have the same size.
The shape of the light emitting device is not limited to the above shape, and may be polygonal such as hexagonal when viewed from above.

A light emitting device 100 includes a light emitting element 10 , a covering member 20 and an optical member 30 . The covering member 20 is arranged to cover the side surface 11 c of the light emitting element 10 . The optical member 30 is arranged over the light emitting surface 11 b of the light emitting element 10 and the upper surface 22 of the covering member 20 .

(light emitting element)
The light emitting device 10 includes a laminated structure 11 including semiconductor layers and an electrode 12 . The laminated structure 11 includes an electrode forming surface 11a and a light emitting surface 11b opposite to the electrode forming surface 11a. The electrode 12 includes a positive electrode 12p and a negative electrode 12n. The electrode formation surface 11 a of the laminated structure 11 is also the electrode formation surface of the light emitting element 10 . The light emitting surface 11 b of the laminated structure 11 is also the light emitting surface of the light emitting element 10 .

The laminated structure 11 includes a semiconductor layer including a light emitting layer. Furthermore, a translucent substrate such as sapphire may be provided. An example of a semiconductor laminate includes three semiconductor layers of a first conductivity type semiconductor layer (e.g., n-type semiconductor layer), a light emitting layer (active layer), and a second conductivity type semiconductor layer (e.g., p-type semiconductor layer). can be done. The semiconductor layer capable of emitting ultraviolet light and visible light ranging from blue light to green light can be formed of semiconductor materials such as III-V group compound semiconductors, for example. Specifically, a nitride-based semiconductor material such as In _X Al _Y Ga _1-XY N (0≦X, 0≦Y, X+Y≦1) can be used. GaAs, GaAlAs, GaP, InGaAs, InGaAsP, or the like can be used as a semiconductor laminate capable of emitting red light. The thickness of the laminated structure 11 can be, for example, 3 μm to 500 μm.

Electrode 12 can be formed of any thickness and of materials and configurations known in the art.
Moreover, as the electrode 12, an electrically good conductor can be used, for example, Cu, Ni, Sn, Fe, Ti, Au, Ag, Pt, etc. can be used. As the electrode 12, AuSn, SnAgCu, or SnPb solder may be used. The electrode 12 can be constructed by laminating a single layer or multiple layers of these metals or solders. The surface is covered with stable metals such as Au, Ag, and Pt. In this way, by constructing the main part made of an inexpensive metal and the stable metal film covering the outermost surface thereof, the electrode 12 can be made inexpensive, and deterioration of solder wettability due to oxidation can be suppressed. Also, an adhesion layer such as Ti, Ni, Mo, W, Ru, Pt, etc. may be formed between the surface layer made of Au, Ag, Pt and the main portion made of Cu, Ni, Fe, Sn. These adhesion layers act as bases for the surface layer to improve adhesion to the main part, control the diffusion of solder to reduce voids during solder bonding, and maintain stable strength over a long period of time.
The electrode 12 can have a thickness of, for example, 1 μm to 300 μm, preferably 5 μm to 100 μm, more preferably 10 μm to 50 μm. When forming the surface layer, for example, Au, Ag, Pt or the like is formed to a thickness of 0.001 μm to 1 μm, preferably 0.01 to 0.1 μm. By forming the surface layer within such a thickness range, oxidation of the electrode surface can be prevented and deterioration of solder wettability can be suppressed while suppressing an increase in cost. The adhesion layer of Ti, Ni, Mo, W, Ru, Pt, etc. formed between the surface layer and the main portion has a thickness in the range of, for example, 0.001 to 1 μm, preferably 0.001 to 0.05 μm. Form to thickness. Various shapes can be selected for the top view shape of the electrode 12 according to the purpose, application, and the like. In FIG. 1C, the electrodes 12n, 12p are each of the same shape and rectangular. Electrodes 12n, 12p may be shaped differently to indicate polarity. For example, it can be shaped like a rectangle with one side or corner notched. The lower surface of the electrode 12 is exposed from the covering member 20 and can function as an external connection terminal. Although only the lower surface of the electrode 12 is exposed from the covering member 20 here, part or all of the side surface of the electrode 12 may be exposed from the covering member 20 .

(coating member)
The covering member 20 is light reflective and covers the side surface 11c of the light emitting element 10 directly or indirectly. In other words, the inner side surface 24 of the covering member 20 contacts or faces the side surface 11 c of the light emitting element 10 . In the light emitting device 100 illustrated in FIG. 1B, the covering member 20 is in contact with the side surface 11c of the light emitting element 10. As shown in FIG.

The outer side surface 23 of the covering member 20 constitutes the side surface 103 of the light emitting device 100 together with the side surface 33 of the optical member 30 which will be described later. The outer side surface 23 of the covering member 20 and the side surface 33 of the optical member 30 are preferably flush with each other.

The covering member 20 covers the electrode formation surface 11a of the laminated structure 11 so that at least a portion of each of the pair of electrodes 12p and 12n of the light emitting element 10 is exposed. Specifically, the covering member 20 exposes the lower surface of the electrode 12p and the lower surface of the electrode 12n, and covers the side surface of the electrode 12p and the side surface of the electrode 12n. The lower surface 21 of the covering member 20 constitutes part of the lower surface 101 of the light emitting device 100 . In the light-emitting device 100 shown in FIG. 1B, the lower surface 21 of the covering member 20 and the lower surface of the electrode 12 are positioned on the same plane. The covering member that covers the lower surface of the laminated structure preferably has a thickness equal to the thickness of the electrode 12, for example, in the range of 5 to 100 μm, so that the lower surface 21 of the covering member 20 and the lower surface of the electrode 12 are positioned on the same plane. is formed to a thickness of 10-50 μm. When the lower surface of the laminated structure is covered with a coating member having a thickness within this range, the amount of light emitted from the lower surface of the laminated structure can be reduced (light leakage can be suppressed). The thickness of the covering member that covers the lower surface of the laminated structure can be appropriately set, for example, in consideration of the concentration of TiO2 contained in the covering member. As described above, for example, the lower surface 21 of the covering member 20 and the lower surface of the electrode 12 are positioned on the same plane. may have steps. In that case, the lower surface of the electrode 12 may protrude from the lower surface 21 of the covering member 20 or may be recessed. The step between the lower surface of the electrode 12 and the lower surface 21 of the covering member 20 is, for example, 0.1 to 30 μm, preferably 0.5 to 20 μm, in order to ensure stable connection with high connection strength and low connection resistance. More preferably, the range is 0.5 to 10 μm. For example, if the electrode 12 is formed so as to protrude from the lower surface 21 of the covering member 20, the solder can be joined to the side surface of the protruding portion, so that the joining strength can be increased. Further, by forming the electrode 12 with the lower surface of the electrode 12 recessed from the lower surface 21 of the covering member 20, tilting of the light emitting device during mounting can be suppressed, and variation in the alignment direction of the light emitting device after mounting can be reduced.

The upper surface 22 of the covering member 20 is in contact with the lower surface 31 of the optical member 30 . In the light-emitting device 100 shown in FIG. 1B, the upper surface 22 of the covering member 20 and the light-emitting surface 11b of the light-emitting element 10 are positioned on the same plane.

The covering member 20 is a member capable of reflecting light from the light emitting element 10, and can be made of, for example, a resin material containing a light reflecting substance. The coating member 20 preferably has a reflectance of 70% or more, more preferably 80% or more, and more preferably 90% or more with respect to the light from the light emitting element 10 .

The base material of the covering member 20 is preferably a resin material containing a thermosetting resin such as a silicone resin, a modified silicone resin, an epoxy resin, or a phenol resin as a main component. For example, a white substance can be used as the light-reflecting substance contained in the resin material. Specifically, for example, titanium oxide, silicon oxide, zirconium oxide, potassium titanate, aluminum oxide, aluminum nitride, boron nitride, mullite and the like are suitable.
The light-reflecting substance can be used in the form of granules, fibers, flakes, or the like.

(optical member)
The optical member 30 is a member for controlling light distribution characteristics of the light emitting device 100 . FIG. 1D is a schematic perspective view of the optical member 30 of the light emitting device 100 shown in FIG. 1A, viewed from the bottom side. The optical member 30 is a plate-shaped member arranged over the light emitting surface 11 b of the light emitting element 10 and the upper surface 22 of the covering member 20 . The optical member 30 has a two-layer structure at least in the vertical direction, with the light reflecting portion 50 on the upper side and the light transmitting portion 40 on the lower side. The upper surface 52 of the light reflecting portion 50 is the upper surface 32 of the optical member 30 and also the upper surface 102 of the light emitting device 100 . The side surface 53 of the light reflecting portion 50 is part of the side surface 33 of the optical member 30 and part of the side surface 103 of the light emitting device 100 . A side surface 43 of the translucent portion 40 is a part of the side surface 33 of the optical member 30 and a part of the side surface 103 of the light emitting device 100 . The lower surface 41 of the translucent portion 40 is part or all of the lower surface 31 of the optical member 30 , and faces at least the upper surface 22 of the covering member 20 .

In Embodiment 1, the translucent part 40 is arranged above the light emitting element 10 in addition to above the covering member 20 . In other words, the lower surface 41 of the translucent portion 40 faces the light emitting surface 11 b of the light emitting element 10 . As a result, the light emitting surface 11 b of the light emitting element 10 and the lower surface 51 of the light reflecting section 50 are arranged to face each other with the light transmitting section 40 interposed therebetween. The light can be efficiently reflected by using 51 so that the light can be easily extracted to the outside from the light emitting surface on the side.

The thickness T _{2 O} of the optical member 30 can be the same throughout. That is, the lower surface 31 and the upper surface 32 of the optical member 30 are both flat surfaces and can be made parallel to each other. By making the upper surface 32 of the optical member 30 flat as shown in FIG. 1B, for example, when the light emitting device is transferred by being sucked by a collet or the like, it can be sucked with high accuracy. However, the upper surface 32 and the lower surface 31 of the optical member 30 may have surfaces that are not parallel partially or entirely. The thickness _TO of the optical member 30 can be appropriately selected according to the size of the light emitting element 10, the size of the light emitting device 100, the light distribution characteristics of the light emitting device 100, and the like. For example, the thickness T 2 _O of the optical member 30 can be about 20% to 80% of the thickness of the light emitting device 100 .

(Translucent part of optical member)
The light transmitting portion 40 arranged on the lower surface 31 side of the optical member 30 is a member for propagating the light from the light emitting element 10 . Translucent resin material, glass, or the like can be used for the translucent portion 40 . For example, thermosetting resins such as silicone resins, silicone-modified resins, epoxy resins, and phenol resins can be used. Thermoplastic resins such as polycarbonate resins, acrylic resins, methylpentene resins, and polynorbornene resins can also be used. In particular, silicone resins, which are excellent in light resistance and heat resistance, are suitable. The translucent portion 40 preferably has a transmittance of 70% or more, more preferably 80% or more, and more preferably 90% or more with respect to the light from the light emitting element. The translucent portion 40 does not substantially contain a phosphor, which will be described later. Also, diffusion materials and the like are not included. It consists only of the above-mentioned resin material or glass. As a result, scattering of light inside the translucent portion 40 is suppressed, and the light reflected by the lower surface 51 of the light reflecting portion 50 and the upper surface 22 of the covering member 20 is efficiently transferred to the side surface 43 of the translucent portion 40 . can be emitted to the outside.

A side surface 43 of the translucent portion 40 is a surface through which light from the light emitting element 10 is emitted to the outside, and is a light emitting surface of the light emitting device 100 . As shown in FIGS. 1A and 1B, the side surfaces 43 of the translucent portion 40 are arranged on all four side surfaces 103 of the rectangular light emitting device 100 . That is, the light-emitting device 100 has light-emitting surfaces on the four side surfaces 103 . As a result, the light emitting device 100 has light emitting surfaces extending 360 degrees around the light emitting device 100 when viewed from above.

In this way, on the side surface 103 of the light-emitting device 100, the light-transmitting portion 40 sandwiched between the covering member 20 and the light-reflecting portion 50 is used as the light-emitting surface. The light is emitted to the outside from a light emitting surface having a smaller area than the thickness of the . Therefore, the light emitted to the side of the light emitting device 100 can be emitted farther.

In the plate-shaped optical member 30 having the same thickness as a whole, the thickness of the translucent portion 40 or the thickness of the light reflecting portion 50 can also be the same. In other words, it is possible to have a plate-like light transmitting portion 40 and a plate-like light reflecting portion 50 . Preferably, as shown in FIG. 1B, in cross-sectional view, the thickness _{TT1 of the side surface 43 of the translucent portion 40 is thicker than the thickness TT2 of} the central portion. The thickness T _{2 T1} of the side surface 43 of the translucent portion 40 can be 50% to 100% of the thickness T 2 _O of the optical member 30 . That is, the thickness T _T1 of the side surface 43 of the translucent portion 40 and the thickness T _O of the optical member may be the same. Further, the thickness T _{2 T2} at the central portion of the translucent portion 40 can be 0% to 90% of the thickness T 2 _O of the optical member 30. FIG. In other words, the thickness T _T2 of the light reflecting portion 50 and the thickness T _O of the optical member 30 may be the same at the central portion of the translucent portion 40 .

(Light reflecting portion of optical member)
The light reflecting portion 50 of the optical member 30 is a member for reflecting the light from the light emitting element 10 toward the side surface 43 of the translucent portion 40 which is the light emitting surface. For the light reflecting section 50, for example, a resin material containing a light reflecting substance or a metal material can be used. Alternatively, an inorganic material using a dielectric multilayer film can be used. The light reflecting portion 50 preferably has a reflectance of 70% or more, more preferably 80% or more, and more preferably 90% or more, with respect to the light from the light emitting element.

When a light-reflecting resin material in which a light-reflecting substance is dispersed is used as the light-reflecting part 50, for example, a white substance can be used as the light-reflecting substance. Specifically, for example, titanium oxide, silicon oxide, zirconium oxide, potassium titanate, aluminum oxide, aluminum nitride, boron nitride, mullite and the like are suitable. The light-reflecting substance can be used in the form of granules, fibers, flakes, or the like. Thermosetting resins such as silicone resins, silicone-modified resins, epoxy resins, and phenol resins can be used as the base material.

When a metal material having a high light reflectance is used as the light reflecting portion 50, examples thereof include silver, aluminum, rhodium, gold, copper, and alloys thereof, and one or more of them may be combined.

When a dielectric multilayer film is used as the light reflecting section 50, for example, those using titanium oxide, silicon oxide, zirconium oxide, potassium titanate, aluminum oxide, aluminum nitride, and the like can be used.

The light reflecting portion 50 has a lower surface 51 functioning as a reflecting surface for reflecting light incident on the light transmitting portion 40 . The lower surface 51 of the light reflecting portion 50 can be a surface parallel to the light emitting surface 11 b of the light emitting element 10 . Preferably, it can also be a convex surface that is convex toward the light emitting surface 11b side. Thereby, the light from the light emitting element 10 can be easily reflected toward the light emitting surface (the side surface 43 of the translucent portion 40) located on the side surface of the light emitting device.

Furthermore, when the lower surface 51 of the light reflecting portion 50 is a convex surface, the top portion R, which is the portion closest to the light emitting surface 11b of the light emitting element 10, is arranged so as to coincide with the center of the light emitting element 10 when viewed from above. preferably. As a result, the light from the light-emitting element 10 can be easily emitted evenly toward the outside from all the light-emitting surfaces on the sides of the light-emitting device.

The light reflecting portion 50 preferably has a thickness such that the transmittance of light from the light emitting element 10 is about 50% or less. As shown in FIG. 1B, when the light reflecting portion 50 is a member with a different thickness, the thickness is such that the light transmittance from the light emitting element 10 is less than about 50% at the thinnest portion. is preferred.

When the optical member 30 is flat, it is preferable that the thickness _TR1 at the side surface 53 of the light reflecting portion 50 is thinner than the thickness _TR2 at the top portion R located in the center.

When a resin material or the like containing a light reflecting substance is used as the light reflecting portion 50, the light transmittance changes depending on the composition, content, or the like of the light reflecting substance. Therefore, the thickness and the like are appropriately adjusted according to the material to be used. For example, in the case of the light reflecting portion 50 using a resin material containing about 70 wt % of titanium oxide and having a thick central portion and a thin side surface 53 as shown in _FIG. is preferably from 0 μm to 300 μm, more preferably from 20 μm to 100 μm.

The thickness T _R2 at the top R of the light reflecting portion 50 may be the same as the thickness T _O of the optical member 30 . In other words, in the thickness direction of the optical member 30, there may be a region where the translucent portion 40 does not exist.

The lower surface 51 of the light reflecting portion 50 can be conical. For example, as shown in FIG. 1B, it is preferable to form a conical shape, which is a slanted surface 53 from which the central portion is the apex R and which is slanted from the apex R to the side surface 53 . The inclined surface may be an inclined surface that is straight in a cross-sectional view, as shown in FIG. 1B. In that case, the angle θ of the inclined surface (the angle from the horizontal plane) is, for example, preferably 10 degrees to 80 degrees, and more preferably 20 degrees to 60 degrees.

Modified examples of the light reflecting portion 50 will be described later.

<Embodiment 2>
A light emitting device 200 according to Embodiment 2 is shown in FIGS. 2A and 2B. The light-emitting device 200 has the same external shape as the light-emitting device 100 shown in FIG. It is different in that it has In addition, the light guide member 60, the wavelength conversion member 70, and the metal layer 80 may be provided with all of these, or may be provided with any one or two. The light guide member 60, the wavelength conversion member 70, and the metal layer 80 will be mainly described below. Since other configurations can be the same as those of the first embodiment, description thereof will be omitted as appropriate.

(light guide member)
The light guide member 60 is a member arranged to cover the side surface 11 c of the light emitting element 10 and is a member for guiding the light emitted from the side surface 11 c of the light emitting element 10 to the optical member 30 . A translucent resin material can be used for the light guide member 60 . For example, resin materials containing thermosetting resins such as silicone resins, silicone-modified resins, epoxy resins, and phenol resins as main components are preferable. The light guide member 60 preferably has a transmittance of 70% or more, more preferably 80% or more, and more preferably 90% or more with respect to the light from the light emitting element.

The light guide member 60 preferably covers 50% or more of the side surface 11 c of the light emitting element 10 .
Moreover, the light guide member 60 may cover the light emitting surface 11 b of the light emitting element 10 . An outer surface 63 of the light guide member 60 is covered with the covering member 20 . Therefore, the light emitted from the side surface 11c of the light emitting element 10 enters the light guide member 60 and is reflected upward (toward the light emitting surface 11b of the light emitting element 10) by the outer surface 63 of the light guide member 60. The light enters the translucent portion 40 of the optical member 30 . By providing such a light guide member 60 , the light from the light emitting element 10 can efficiently enter the light transmitting portion 40 of the optical member 30 .

The upper surface 62 of the light guide member 60 is connected to the lower surface 31 of the optical member 30 so as to be optically continuous directly or indirectly. Specifically, it is optically directly or indirectly connected to the lower surface 41 of the translucent portion 40 of the optical member 30 . The light-emitting device 200 shown in FIG. 2A includes a wavelength conversion member 70 between the light-emitting surface 11b of the light-emitting element 10 and the lower surface 31 of the optical member 30, and the upper surface 62 of the light guide member 60 is the lower surface of the wavelength conversion member 70. It is in contact with 71. Since the wavelength conversion member 70 is a translucent member as will be described later, the light emitted from the side surface 11c of the light emitting element 10 enters the light guide member 60 and then enters the wavelength conversion member 70. , and then enter the translucent portion 40 of the optical member 30 . That is, the light guide member 60 and the optical member 30 are optically and indirectly connected via the wavelength conversion member 70 therebetween. When the wavelength conversion member 70 is provided, the light guide member 60 and the optical member 30 are preferably connected with the wavelength conversion member 70 interposed therebetween.

As shown in the bottom view of FIG. 2B, the light guide member 60 can have an upper surface 62 with a substantially circular outer shape. The light guide member 60 having such a shape can be formed by forming the liquid light guide member 60 on the flat plate-like optical member 30 by potting or the like in the manufacturing method of the light emitting device described later. .

(Wavelength conversion member)
The wavelength conversion member 70 contains a phosphor that absorbs light from the light emitting element 10 and converts it into light of different wavelengths. The wavelength converting member 70 is arranged between the light emitting surface 11 b of the light emitting element 10 and the lower surface 31 of the optical member 30 . Specifically, the wavelength conversion member 70 is arranged between the light emitting surface 11 b of the light emitting element 10 and the lower surface 41 of the light transmitting portion 40 of the optical member 30 . By arranging the wavelength converting member 70 between the light emitting element 10 and the light transmitting portion 40, mixed light of light from the light emitting element 10 and light from the wavelength converting member 70 is incident on the light transmitting portion 40. be done. A light guide member 60 may be arranged between the wavelength conversion member 70 and the light emitting element 10 .

The wavelength conversion member 70 preferably covers the entire light emitting surface 11b of the light emitting element 10, as shown in FIG. 2A and the like. In other words, the width (area) of the lower surface 71 and upper surface 72 of the wavelength conversion member 70 is preferably larger than the width (area) of the light emitting surface 11 b of the light emitting element 10 . When the light guide member 60 is provided on the side surface 11 c of the light emitting element 10 , the wavelength conversion member 70 preferably covers the entire light emitting surface 11 b of the light emitting element 10 and the entire upper surface 62 of the light guide member 60 . In other words, the width of the lower surface 71 and the upper surface 72 of the wavelength conversion member 70 is larger than the width (area) of the width (area) of the light emitting element 10 plus the width (area) of the upper surface 62 of the light guide member 60. is preferred. The bottom surface 71 and the top surface 72 of the wavelength converting member 70 can be the same size or different sizes. Also, the side surface 73 of the wavelength conversion member 70 can be a vertical surface, an inclined surface, a curved surface, or the like.
The outer shape of the wavelength conversion member 70 (the outer shape when viewed from above) is preferably similar to the outer shape of the light emitting surface of the light emitting element 10 . In this way, by arranging the central axis of the light emitting surface of the light emitting element 10 and the central axis of the wavelength conversion member 70 to substantially match, the wavelength converting member 70 positioned outside the light emitting surface of the light emitting element 10 The width of the outer peripheral portion can be made substantially constant, and color unevenness can be suppressed. That is, if the width of the outer peripheral portion of the wavelength conversion member 70 located outside the light emitting surface of the light emitting element 10 is not constant, the amount of light converted by the wavelength conversion member varies depending on the direction, resulting in color unevenness. Although there is a risk, color unevenness can be suppressed by making the width of the outer peripheral portion of the wavelength conversion member 70 constant.

Side surface 73 of wavelength conversion member 70 is preferably spaced apart from side surface 203 of light emitting device 200 . In other words, the width (area) of the first surface 71 and the second surface 72 of the wavelength conversion member 70 is preferably smaller than the width (area) of the light emitting surface 11 b of the light emitting device 200 . The top view shape of the wavelength conversion member 70 can be a quadrangle, a circle, a polygon, or the like. The thickness of the wavelength conversion member 70 can be appropriately selected according to the type and amount of phosphor to be used, the desired chromaticity, and the like. For example, the thickness of the wavelength conversion member 70 can be 20 μm to 200 μm, preferably 40 μm to 180 μm, more preferably 60 μm to 150 μm.
Also, the wavelength conversion member 70 may be composed of a plurality of layers containing different types of phosphors. By containing different types of phosphors in a plurality of layers, mutual absorption of the phosphors can be suppressed, wavelength conversion efficiency can be improved, and a light emitting device with high light output can be obtained. For example, when the wavelength conversion member 70 is composed of two layers, the thickness of each layer is set in the range of 10 to 100 μm, more preferably in the range of 40 to 80 μm.

The wavelength conversion member 70 includes a base material such as translucent resin material or glass, and a phosphor as a wavelength conversion material. Thermosetting resins such as silicone resins, silicone-modified resins, epoxy resins, and phenol resins can be used as the base material. Thermoplastic resins such as polycarbonate resins, acrylic resins, methylpentene resins, and polynorbornene resins can also be used. In particular, silicone resins, which are excellent in light resistance and heat resistance, are suitable. The base material preferably has a transmittance of 70% or more, more preferably 80% or more, and more preferably 90% or more, with respect to the light from the light emitting element.

A phosphor that absorbs light from the light emitting element 10 and converts it into light of a different wavelength is used. In other words, one that can be excited by light emitted from the light emitting element 10 is used. For example, phosphors that can be excited by a blue light emitting device or an ultraviolet light emitting device include a cerium-activated yttrium aluminum garnet phosphor (YAG:Ce); a cerium activated lutetium aluminum garnet phosphor (LAG:Ce); nitrogen-containing calcium aluminosilicate phosphor activated with europium and/or chromium (CaO—Al ₂ O ₃ —SiO ₂ ); silicate phosphor activated with europium ((Sr, Ba) ₂ SiO ₄ ); Nitride-based phosphors such as β-sialon phosphors, CASN-based phosphors, and SCASN-based phosphors; KSF-based phosphors (K ₂ SiF ₆ :Mn); Sulfide-based phosphors, quantum dot phosphors etc. By combining these phosphors with blue light emitting elements or ultraviolet light emitting elements, light emitting devices of various colors (for example, white light emitting devices) can be manufactured. One or a plurality of these phosphors can be used. When using a plurality of them, they may be mixed or laminated.
Further, the wavelength conversion member may contain various fillers for the purpose of adjusting the viscosity.

(metal layer)
The metal layer 80 is a conductive member and can function as an external connection terminal of the light emitting device 200 .

Metal layer 80 is electrically connected to electrodes 12n and 12p of light emitting element 10, respectively.
The metal layer 80 can be arranged to cover a portion of the lower surface 21 of the cover member 20 . In other words, on the bottom surface of the light emitting device 200 , the metal layer 80 can be arranged from the electrode 12 of the light emitting element 10 to the bottom surface 21 of the covering member 20 . As a result, the lower surface of the light emitting device 200 can be exposed to the outside as external connection terminals having a larger area than the electrodes 12 of the light emitting element 10 . By making the area of the metal layer 80 larger than the electrode 12 of the light emitting element 10, the light emitting device 200 can be mounted on a wiring board or the like using solder or the like with high positional accuracy. Also, the bonding strength between the wiring board and the light emitting device 200 can be improved.

For the metal layer 80 , it is preferable to select a material that is superior in corrosion resistance and oxidation resistance to the electrode 12 of the light emitting element 10 . The metal layer 80 may be composed of only one layer of a single material, or may be composed of laminated layers of different materials. In particular, it is preferable to use a metal material with a high melting point, such as Ru, Mo, Ta, and the like. In addition, by providing these high melting point metal materials between the electrode of the light emitting element and the outermost layer, Sn contained in the solder is prevented from diffusing into the electrode of the light emitting element and layers close to the electrode. can be a diffusion prevention layer capable of Ni/Ru/Au, Ti/Pt/Au and the like are given as examples of laminated structures having such a diffusion barrier layer. Also, the thickness of the diffusion prevention layer (eg, Ru) is preferably about 10 Å to 1000 Å.

Various thicknesses of the metal layer 80 can be selected. The thickness of the metal layer 80 can be, for example, 10 nm to 3 μm. Here, the thickness of the metal layer 80 means the total thickness of the plurality of layers when the metal layer 80 is configured by laminating a plurality of layers.

The metal layer 80 can be sized to reach the side surface 203 on the bottom surface of the light emitting device 200 . Also, the metal layer 80 can be sized to be spaced apart from the side surface 203 on the bottom surface of the light emitting device 200 . The metal layers 80 can have the same shape and size, or different shapes and sizes in bottom view. For example, either one of the metal layer 80 connected to the electrode 12n and the metal layer 80 connected to the electrode 12p may be provided with a notch or the like so as to function as a cathode mark or an anode mark.

<Embodiment 3>
A light-emitting device according to Embodiment 3 is shown in FIGS. 3A and 3B. The light emitting device 300A and the light emitting device 300B have the same external shape as the light emitting device 100 and the like shown in FIG. 1A. Further, while the light guide member 60 is arranged on the side surface 11c of the light emitting element 10 in the second embodiment described above, the light guide member 60A is arranged on the side surface 73 of the wavelength conversion member 70 in the third embodiment. There is a difference.

In the light emitting device 300B, the light guide member 60 is arranged on the side surface of the light emitting element 10, and the light guide member 60A is arranged on the side surface of the wavelength conversion member . In such a case, it is preferable to arrange the light guide member 60 and the light guide member 60B so as not to be optically continuous. If the light guide member 60 and the light guide member 60A are optically continuous, light that does not pass through the wavelength conversion member 70 enters the light transmitting portion 40, which causes color unevenness, which is not preferable.

60 A of light guide members arrange|positioned at the side surface 73 of the wavelength conversion member 70 are preferably arrange|positioned so that it may space apart from the side surface 303 of light-emitting devices 300A and 300B. In other words, the light guide member 60A is preferably embedded in the covering member 20. As shown in FIG. Also, although the example shown in FIGS. 3A and 3B includes a metal layer 80, this is not essential.

<Modified example of optical member>
The light emitting devices shown in FIGS. 4A to 4E are modifications of the optical members illustrated in the first to third embodiments. Here, as an example, a light-emitting device including a wavelength conversion member, a light guide member, a metal layer, etc. is illustrated, but these members are not essential.

The optics shown in FIGS. 4A to 4E have in common that the lower surface of the light reflecting portion is convex downward at the center.

In the light emitting device 400A shown in FIG. 4A, the light reflecting portion 50A of the optical member 30A has a curved lower surface 51A. That is, it can be hemispherical or parabolic of revolution. The lower surface 51A of the light reflecting portion 50A has a top portion R that is closest to the light emitting element 10 in the vicinity of the central portion thereof. The top portion R is a curved surface, and the lower surface 51B between the top portion R and the side surface 403 of the light emitting device 400A is a curved surface that protrudes toward the side surface.

In the light emitting device 400B shown in FIG. 4B, the lower surface 51B of the light reflecting portion 50B of the optical member 30B has a curved shape that is convex toward the upper surface with the apex R sandwiched therebetween. be. Specifically, the lower surface 51B of the light reflecting portion 50B is a curved surface that is concave with respect to the side surface 403 of the light emitting device 400B. As shown in FIG. 4B, by using a curved surface that is concave with respect to the side surface 403 as a reflecting surface, light can be spread farther than the light emitting device 400A shown in FIG. 4A.

In addition, by forming the lower surface of the light reflecting portion into a curved surface as shown in FIG. 4A and FIG. , the orientation can be controlled while reducing the loss of brightness. When the lower surface of the light reflecting portion is curved, the curvature of the curved surface is, for example, 1/(length of wavelength conversion member L×0.5) to 1/(length of wavelength conversion member L×20), preferably is in the range of 1/(length L of wavelength conversion member) to 1/(length L×10 of wavelength conversion member). By setting the curved surface within this range, light can be effectively reflected in the lateral direction, and a light emitting device with high light output can be obtained.
Here, the length L of the wavelength conversion member is the length of the diagonal line when the outer shape of the wavelength conversion member is rectangular, and the length L of the wavelength conversion member is the diameter when the outer shape of the wavelength conversion member is circular. Say.

In the light emitting device 400C shown in FIG. 4C, the light reflecting portion 50C of the optical member 30C has a convex portion 50Ca near the center portion on the lower surface 51C side thereof, and a planar portion 50Cb around the convex portion 50Ca. That is, the lower surface 51 of the light reflecting portion 50 of the optical member 30 illustrated in FIG. 1B and the like is entirely inclined or curved, whereas the lower surface 51C of the light reflecting portion 50C shown in FIG. 4C is partially inclined. is the lower surface 51Ca of the convex portion 50Ca, which is an inclined surface. Here, the lower surface 51Ca of the convex portion 50Ca shows an example in which the lower surface 51Ca of the convex portion 50Ca is an inclined surface that becomes a straight line in a cross-sectional view, but is not limited to this, and may be a convex curved surface as shown in FIGS. 4A and 4B, Alternatively, the lower surface 51Ca may have a concave curved surface.

The convex portion 50Ca of the light reflecting portion 50C is arranged above the light emitting element 10. As shown in FIG. The convex portion 50Ca is preferably arranged near the center of the optical member 30C. Furthermore, it is preferable that the apex R of the convex portion 50Ca and the center of the wavelength conversion member 70 match when viewed from above. However, since light propagates through the wavelength converting member 70, even if the center of the light emitting element 10 and the center of the convex portion 50Ca are slightly misaligned, the center of the wavelength converting member 70 and the center of the convex portion 50Ca are aligned. 4C shows an example in which the width W _R1 of the convex portion 50Ca of the light reflecting portion 50C, in which the light tends to spread uniformly, is smaller than the width W _D of the light emitting element 10. As shown in FIG. Not limited to this, the width W _R1 of the convex portion 50Ca may be the same as the width W _D of the light emitting element 10, or may be larger than the width W _D of the light emitting element 10 depending on the desired light distribution.

The plane portion 50Cb of the light reflecting portion 50C is a surface parallel to the lower surface 31C of the optical member 30C (the lower surface 41C of the transmitting portion 40C), and the thickness of the light reflecting portion 50C in this region is constant.

In the light emitting device 400D shown in FIG. 4D, the upper surface 32D of the optical member 30D (the upper surface 52D of the light reflecting section 50D) has a concave shape. The light transmitting portion 40D of the light emitting device 400D has the same shape as the light transmitting portion 40 of the light emitting device 100 shown in FIG. 1B, and the shape of the upper surface 52D of the light reflecting portion 50D is different. Furthermore, the light reflecting portion 50D is formed with the same thickness over its entirety. For example, when a metal film or an insulating reflecting film formed by sputtering or the like is used as the light reflecting portion 50D, it can be formed so as to have the same thickness as a whole. Also, the light reflecting portion 50D shown in FIG. 4D may have a lower surface with a convex curved surface or a concave curved surface as shown in FIGS. 4A and 4B.

In the case of a light reflecting portion having a concave upper surface as shown in FIG. 4D, a filling member such as a resin material may be further provided thereon. For example, in the light emitting device 400E shown in FIG. 4E, the light reflecting portion 50E has a concave upper surface 52E. A filling member 54 is arranged on the upper surface 52E of the concave light reflecting portion 50E. The upper surface of the filling member 54 becomes the upper surface 32E of the optical member 30E. In this manner, the upper surface 52E of the light reflecting portion 50E and the upper surface 32E of the optical member 30E may be different. By making the upper surface of the filling member 54 flat, for example, it can be easily sucked by a collet or the like. The light reflecting portion 50E shown in FIG. 4E may also have a lower surface with a convex curved surface or a concave curved surface as shown in FIGS. 4A and 4B.

<Manufacturing method>
A method for manufacturing the light emitting device according to Embodiments 1 to 3 will be described with reference to FIGS. 5A to 5H. Here, the light emitting device according to Embodiment 2 will be described as an example. That is, a method for manufacturing a light-emitting device including a light guide member, a wavelength conversion member, a metal layer, and the like will be described. To obtain a light-emitting device that does not include these members, the step of forming the members is omitted.

(Preparation of light reflecting part)
First, as shown in FIG. 5A, the light reflecting portion 50 is prepared. The light reflecting portion 50 is a plate-like member. The light reflecting portion 50 includes a flat second surface 52 and a first surface 51 having a convex portion. One light reflecting portion 50 can have one or more convex portions. Here, the light reflecting portion 50 having two convex portions will be described as an example. In FIG. 5A, the second surface 52 is arranged on the lower side and the first surface 51 is arranged on the upper side. The first surface 51 corresponds to the lower surface 41 of the light reflecting portion 50 of the light emitting device 100 , and the second surface 52 corresponds to the upper surface 52 of the light reflecting portion 50 of the light emitting device 100 . In the manufacturing process, the top and bottom may be reversed as shown in FIG. 5A and the like, so for convenience of explanation, the first surface and the second surface are used instead of the bottom surface and the top surface.

The light reflecting portion 50 may be prepared by purchasing the light reflecting portion 50 having the shape described above, or may be prepared using the following materials through processes such as molding.

A case in which the light reflecting portion 50 is formed using a light reflecting resin material in which a light reflecting substance is dispersed will be described. The light reflecting portion 50 made of a light reflecting resin material can be formed by injection molding, transfer molding, compression molding, or the like using a mold or the like. Alternatively, a plate-like member as shown in FIG. 5A is prepared with another resin material or the like, and injection molding, transfer molding, or compression molding is performed in the same manner as described above on the first surface 51 that serves as a reflecting surface for reflecting light from the light emitting element. The light reflecting portion 50 may be formed by forming a light reflecting layer by a method such as molding, or by printing, spraying, sputtering, or the like.

A case in which the light reflecting portion 50 is formed using a metal material will be described. When a metal member is used, the entire light reflecting section 50 may be made of a metal material with high light reflectance. In this case, the metal plate can be processed by grinding, bending, or the like to form a metal plate having a convex shape on one side as shown in FIG. 5A. In addition, a plate-shaped member made of the above-mentioned resin material or the like and having a shape shown in FIG. A plated film made of a metal material may be formed to form the light reflecting portion.

A case where a dielectric multilayer film is used as the light reflecting section 50 will be described. As described above, a plate-shaped member made of a resin material or the like and having a shape shown in FIG. 5A is prepared, and a dielectric multilayer film is formed by sputtering or the like on the first surface 51 that serves as a reflection surface for reflecting light from the light emitting element. may be used as the light reflecting portion 50 .

(Formation of translucent portion)
Next, as shown in FIG. 5B, the translucent portion 40 is formed on the first surface 51 of the light reflecting portion 50 . Thereby, the first surface 41 of the light transmitting portion 40 is the first surface 31 of the optical member 30, and the second surface 52 of the light reflecting portion 50 is the second surface 32 of the optical member 30. An optical member 30 can be obtained. The translucent part 40 can be formed, for example, by arranging the above-described light reflecting part 50 in a mold and then molding a translucent resin material by a method such as injection molding, transfer molding, or compression molding. can. Alternatively, a translucent resin material can be formed on the first surface 51 of the light reflecting portion 50 by printing, spraying, or the like. Since the first surface 41 of the translucent part 40 will be the surface on which the light-emitting element is placed in a later process, it is preferable that the first surface 41 be a flat surface.

(Preparation of optical members: modified example)
The optical member 30 can be prepared by forming the light-transmitting portion 40 after preparing the light-reflecting portion 50 as described above. may be formed. In particular, when a metal film or a dielectric multilayer film is used as the light reflecting portion 50, the light transmitting portion 40 is prepared first, and these light reflecting portions 50 are formed on the first surface of the light transmitting portion 40 by a film forming method or the like. It is preferable to form using Such a translucent part 40 may be purchased and prepared.

(Formation of wavelength conversion member)
Next, as shown in FIG. 5C, the wavelength conversion member 70 is arranged on the first surface 31 of the optical member 30 (on the first surface 41 of the light transmitting portion 40). Note that this step is omitted in the manufacturing steps of a light-emitting device that does not include a wavelength conversion member.

The wavelength converting member 70 is provided on the first surface 31 of the optical member 30 (on the first surface 31 of the light transmitting portion 40) and at a position facing the apex R of each convex portion of the light reflecting portion 50. place it. Adjacent wavelength conversion members 70 are spaced apart between the tops R. The center of the wavelength conversion member 70 is preferably arranged so that the apex R of the light reflecting portion 50 is aligned.

The wavelength conversion member 70 can be arranged on the first surface 31 of the optical member 30 by preparing a molded product and using an adhesive or the like. When an adhesive is used, the light guide member 60A can be formed by placing the adhesive on the side surface 73 of the wavelength conversion member 70, as shown in FIG. 3A.

Further, the wavelength conversion member 70 may be formed by printing, spraying, injection molding, compression molding, transfer molding, or the like, on the first surface 31 of the optical member 30 with a liquid resin material containing a phosphor in the resin material. can be done. For example, on the first surface 31 of the optical member 30, a mask or the like having an opening of a desired shape is provided in advance in a region facing the apex R of the light reflecting portion, and the wavelength conversion member 70 is formed in the opening. Then, by removing the mask, it is possible to form the wavelength conversion members 70 separated from each other. Alternatively, the wavelength conversion member 70 is formed on the entire surface of the first surface 31 of the optical member 30, and then other portions are formed so that the wavelength conversion member 70 having a desired shape remains in the region facing the apex R of the light reflecting portion. By removing, the wavelength conversion members 70 spaced apart from each other can be formed. Alternatively, the wavelength conversion member 70 may be formed by potting a liquid resin material on the first surface 31 of the optical member 30 using a dispensing nozzle or the like without using a mask.

The first surface 71 of the wavelength conversion member 70 is a surface on which a light emitting element is placed in a later process.
Therefore, the first surface 71 of the wavelength conversion member 70 preferably has at least a flat surface on which the light emitting element can be placed.

(Formation of light guide member)
Next, as shown in FIG. 5D , the light guide member 60 is arranged on the first surface 31 of the optical member 30 . When the wavelength conversion member 70 is arranged on the first surface 31 of the optical member 30 , the light guide member 60 is arranged on the first surface 71 of the wavelength conversion member 70 . The light guide member 60 arranged here is liquid, and functions as a bonding member for bonding a light emitting element (to be described later) to the optical member 30 or the wavelength conversion member 70. Therefore, it is preferable that the light guide member 60 has a deformable hardness. . Depending on the amount of the liquid light guide member 60, the size of the light guide member 60 arranged on the side surface of the light emitting element can be adjusted. Therefore, it is preferable to adjust the amount of the light guide member 60 according to the size of the light emitting element, the height of the light emitting element, and the like. When the liquid light guide member 60 is arranged on the first surface 71 of the wavelength conversion member 70 , the light guide member 60 is arranged so as to have a size smaller than the area of the first surface 71 of the wavelength conversion member 70 . It is preferable to adjust the amount. Moreover, in the step of forming the liquid wavelength conversion member 70 before this step, the light emitting element may be placed before the liquid wavelength conversion member 70 is cured. That is, the liquid wavelength conversion member 70 itself may be used as the joining member. In such a case, the step of forming the light guide member can be omitted. Also, when an adhesive is applied to the light emitting element side, or when the optical member and the light emitting element are directly bonded, this step of forming the light guide member can be omitted.

(Placement of light emitting element)
Next, as shown in FIG. 5E, the light emitting element 10 is arranged on the light guide member 60 . The light emitting element 10 is arranged so that the electrode 12 faces upward, that is, the laminated structure 11 side faces the light guide member 60 . When the light guide member 60 is liquid, it creeps up on the side surface of the light emitting element 10 to form a fillet-shaped light guide member 60 as shown in FIG. 5E. The light guide member 60 is cured in such a state.

(Formation of covering member)
Next, as shown in FIG. 5F, a covering member 20 is formed on the optical member 30 so as to cover the plurality of light emitting elements 10 integrally. The covering member 20 can be formed up to a height where the electrodes 12 of the light emitting element 10 are embedded. The covering member 20 is formed so as to also embed the first surface 31 of the optical member 30 between the adjacent light emitting elements 10 . The covering member 20 can be formed by, for example, injection molding, transfer molding, compression molding, printing, potting, spraying, or the like.

(Exposed electrode)
Next, as shown in FIG. 5G, the electrode 12 of the light emitting element 10 is exposed by removing part of the covering member 20 . This step is necessary after embedding the electrodes 12 when forming the covering member 20 as described above. That is, when forming the covering member 20, if the upper surface of the electrode 12 is not buried, this step is omitted. Polishing, grinding, blasting, and the like are examples of methods for removing a portion of the covering member 20 .

Next, as shown in FIG. 5H, a metal layer 80 is formed on the exposed pair of electrodes 12 . A metal layer 80 may be coated over the covering member 20 . The metal layer 80 is formed by sputtering, vapor deposition, atomic layer deposition (ALD), metal organic chemical vapor deposition (MOCVD), plasma-enhanced chemical vapor deposition (PECVD). ) method, atmospheric pressure plasma deposition method, plating, or the like.

The metal layer 80 can be formed by patterning, for example, laser light irradiation, etching, etc., after forming the metal layer 80 so as to cover the entire surface including the covering member 20 and the electrodes 12 . Alternatively, it can be formed by forming a patterned mask or the like in advance, then forming the metal layer 80 using the method described above, and then removing the mask. When the metal layer 80 is formed by laser ablation using laser light irradiation, the thickness of the metal layer 80 can be, for example, 10 nm to 3 μm, preferably 1 μm or less, and more preferably 1000 Å or less. Moreover, it is preferable that the thickness be such that corrosion of the electrode 12 can be reduced, for example, 5 nm or more.

(Step of singulating)
Finally, the covering member 20 and the optical member 30 are separated by cutting between adjacent light emitting elements (cutting lines indicated by dashed lines C in FIG. 5H) to obtain light emission as shown in FIG. 2A. A device 200 can be obtained.

<Embodiment 4>
A light emitting device 600 according to Embodiment 4 is shown in FIG. In Embodiment 4, the upper surface 72F and the side surface 73F of the wavelength conversion member 70F are covered with the translucent portion 40F of the optical member 30F. Therefore, the light from the light emitting element 10 enters the translucent portion 40F from the upper surface 72F and the side surface 73F of the wavelength conversion member 70F. Thereby, the light extraction efficiency can be improved.
Differences from Embodiments 1 to 3 will be mainly described below.

(coating member)
In Embodiment 4, the covering member 20F directly or indirectly covers the side surface 11c of the light emitting element 10 and does not cover the side surface 73F of the wavelength conversion member 70F. The upper surface 22F of the covering member 20F is flush with the lower surface 71F of the wavelength converting member 70F.

(optical member)
In Embodiment 4, the optical member 30F has a concave portion 41Fa instead of a flat lower surface 31F. Specifically, the lower surface 41F of the translucent portion 40F of the optical member 30F is not flush but has a concave portion 41Fa. A wavelength converting member 70F is arranged inside the concave portion 41Fa. The lower surface 41F of the translucent portion 40F and the lower surface 71F of the wavelength conversion member 70F are flush with each other. The width (area) of the recess 41Fa is preferably the same as the width (area) of the first surface 71F and the second surface 72F of the wavelength conversion member 70F. Depending on the method of forming the wavelength conversion member 70F, the width of the first surface 71F and the second surface 72F of the wavelength conversion member 70F may be smaller than the width of the recess 41Fa. It is preferable that the center of the concave portion 41Fa and the center of the wavelength conversion member 70F match when viewed from above. In addition, it is preferable that the center of the concave portion 41Fa and the top portion R of the light reflecting portion 50F match when viewed from above. Moreover, it is preferable that the width of the concave portion 41Fa is larger than the width (area) of the light emitting surface of the light emitting element 10 . When the light guide member 60F is provided, the width of the recess 41Fa should be larger than the sum of the width (area) of the light emitting element 10 and the width (area) of the upper surface 62F of the light guide member 60F. is preferred. It is preferable that the depth of the concave portion 41Fa be such that the desired wavelength conversion member 70F can be arranged.

7A to 7D are diagrams showing some steps of a method for manufacturing a light emitting device according to Embodiment 4. FIG. First, as shown in FIG. 7A, the translucent portion 40F is prepared. The translucent part 40F includes a concave portion 41Fa in which a wavelength conversion member can be arranged on the first surface 41F side. An inclined surface is provided on the second surface 42F side. The translucent part 40F may be purchased and prepared. 7A may be prepared in advance by molding or the like, or the light transmitting portion 40F may have a flat surface as the first surface 41F and an inclined surface as the second surface 42F. The concave portion 41Fa may be formed in a separate process, such as forming the concave portion 41Fa after preparing a light-transmitting portion having a surface. Note that the second surface 42F may have the shape shown in FIGS. 4A to 4C.

Next, as shown in FIG. 7B, a light reflecting portion 50F is formed on the second surface 42F side of the translucent portion 40F to obtain an optical member 30F.

Next, as shown in FIG. 7C, the wavelength converting member 70F is arranged in the concave portion 41Fa of the first surface 31F of the optical member 30F (the first surface 41F of the translucent portion 40F). The method of arranging the wavelength conversion member 70F can be the same as in the first to fourth embodiments. In particular, it is preferable to form the liquid wavelength conversion member 70F in the concave portion 41Fa by printing or potting. The first surface 41F of the light transmitting portion 40F and the first surface 71F of the wavelength converting member 70F are at the same height, or the first surface 71F of the wavelength converting member 70F is positioned higher than the first surface 41F of the light transmitting portion 40F. should be at a high position.

Next, as shown in FIG. 7D, a liquid light guide member 60F is arranged on the first surface 71F of the wavelength conversion member 70F. After that, the steps after the step of arranging the light-emitting element 10 are the same as those in Embodiments 1 to 3, and therefore are omitted.

<Embodiment 5>
A light emitting device 800 according to Embodiment 5 is shown in FIG. In Embodiment 5, the side surface 73G of the wavelength conversion member 70G is covered with the translucent portion 40G of the optical member 30G. The upper surface 72G of the wavelength converting member 70G is covered with the light reflecting portion 50G of the optical member 30G. Therefore, the light from the light emitting element 10 enters the translucent portion 40G of the optical member 30G only from the side surface 73F of the wavelength conversion member 70F. Thereby, the light can be spread more laterally. Differences from Embodiments 1 to 4 will be mainly described below.

(coating member)
In Embodiment 5, similarly to Embodiment 4, the covering member 20 directly or indirectly covers the side surface 11c of the light emitting element 10 and does not cover the side surface 73G of the wavelength conversion member 70G.

(optical member)
Embodiment 5 is the same as Embodiments 1 to 4 in that the light transmitting portion 40G and the light reflecting portion 50G of the optical member 30G constitute part of the side surface 803 of the light emitting device 800. FIG. Of the lower surface 51G of the light reflecting portion 50G, a part of the lower surface 51G continuous from the side surface 803 of the light emitting device 800 is in contact with the light transmitting portion 40G, and the lower surface 51G of the light reflecting portion 50G located above the light emitting element 10 is It differs from Embodiments 1 to 4 in that the wavelength converting member 70G is in contact with it. In other words, the translucent portion 40G is not arranged above the wavelength conversion member 70G. As a result, it is possible not only to spread the light more laterally, but also to improve the color unevenness of the emitted light.

Here, as the light reflecting portion 50G, the light reflecting portion 50G including the convex portion 50Ga and the flat portion 50Gb is exemplified, but the light reflecting portion 50G having a shape used in other embodiments is also applicable. be able to.

It is preferable that the width (area) of the lower surface 71G of the wavelength conversion member 70G is larger than the width (area) of the light emitting element 10 . Moreover, when the light guide member 60G is provided as shown in FIG. 8, it is preferable that the wavelength conversion member 70G is also arranged on the upper surface of the light guide member 60G. The width (area) of the upper surface 72G of the wavelength conversion member 70G may be the same as that of the lower surface 71G, or may be larger or smaller. That is, the side surface 73G of the wavelength converting member 70G can be a vertical or inclined surface. Also, the side surface 73G of the wavelength conversion member 70G can be a stepped surface, a curved surface, or the like.

As shown in FIG. 8, the second surface 72G of the wavelength conversion member 70G is entirely in contact with the light reflecting portion 50G. may be in contact with the light reflecting portion 50G. Further, the wavelength conversion member 70G may be in contact with the convex portion 50Ga and the flat portion 50Gb of the light reflecting portion 50G, or may be in contact with only the convex portion 50Ga.

9A to 9D are diagrams showing some steps of the method for manufacturing the light emitting device according to Embodiment 5. FIG. First, as shown in FIG. 9A, the light reflecting portion 50G is prepared. The light reflecting portion 50G includes a convex portion 51Ga and a flat portion 50Gb on the first surface 51G side. It should be noted that the first surface 51G of the light reflecting portion 50G can have the shapes illustrated in the other embodiments.

Next, as shown in FIG. 9B, a translucent portion 40G is formed on a portion of the first surface 51G of the light reflecting portion 50G. Since the translucent part 40G is arranged on the side surface 803 of the light emitting device 800, it is formed at a position where it will be cut later when singulating. Here, the translucent portion 40G is formed on the planar portion 50Gb at a position separated from the convex portion 50Ga of the light reflecting portion 50G. The translucent portion 40G is formed in a grid pattern when viewed from above, although not shown. Therefore, a plurality of recesses 34G having the first surface 51G of the light reflecting portion 50G as the bottom surface and the light transmitting portion 40G as the side walls are formed. The apex R of the projection 50Ga is arranged at the center of the bottom surface of the recess 34G.

Next, as shown in FIG. 9C, the wavelength conversion member 70G is placed inside the recess 34G.

Next, as shown in FIG. 9C, a liquid light guide member 60G is arranged on the first surface 71G of the wavelength conversion member 70G. After that, the steps after the step of arranging the light-emitting element on the light guide member 60G are the same as those in the first to fourth embodiments, so the description thereof will be omitted.

10A to 10D are modifications of the method for manufacturing the light emitting device 800 according to the fifth embodiment.
First, as shown in FIG. 10A, a light reflecting portion 50G is prepared. Next, as shown in FIG. 10B, a wavelength conversion member 70G is formed. After that, as shown in FIG. 10C, by removing the wavelength converting member 70G arranged at the position to be cut in the post-process, the flat portion 50Gb of the light reflecting portion 50G is exposed. Next, as shown in FIG. 10D, the translucent portion 40G is formed on the light reflecting portion 50G between the adjacent wavelength converting members 70G. In this way, even if the wavelength conversion member 70G is formed before the translucent portion 40G, the same optical member 30G as shown in FIG. 9C can be formed.

<Embodiment 6>
The light-emitting device of Embodiment 6 is configured in the same manner as the light-emitting device of Embodiment 1, except that the side surface of the optical member is inclined with respect to the direction perpendicular to the upper surface of the optical member.
Specifically, as shown in FIG. 11A, in a light emitting device of one aspect according to Embodiment 6, the side surface 33H of the optical member 30H is inclined inward at an inclination angle α with respect to the direction perpendicular to the upper surface of the optical member 30H. ing. Here, in this specification, inclining inward means inclining so as to approach the central axis of the optical member as it approaches the upper surface, and the inclination angle when inclining inward is called α.
In the light emitting device of this aspect, the optical member 30H includes the light reflecting portion 50H and the light transmitting portion 40H, as in the first embodiment. When the side surface 53H of the reflecting portion 50H is included, at least the side surface 43H of the translucent portion 40H should be inclined inward in the side surface 33H of the optical member 30H.

Moreover, as shown in FIG. 11B, in a light emitting device of another aspect according to Embodiment 6, the side surface 33I of the optical member 30I is inclined outward at an inclination angle β with respect to the direction perpendicular to the upper surface of the optical member 30I. . Here, in this specification, "tilting outward" means tilting away from the central axis of the optical member as it approaches the upper surface, and the tilt angle when tilting outward is called β.
In the light emitting device of this other aspect, the optical member 30I includes the light reflecting portion 50I and the light transmitting portion 40I, as in the first embodiment, and the side surface 33I of the optical member 30I is the side surface 43I of the light transmitting portion 40I. When the side surface 53I of the light reflecting portion 50I is included, at least the side surface 43I of the light transmitting portion 40I should be inclined outward in the side surface 33I of the optical member 30I.

The light emitting device of Embodiment 6 configured as described above can control the direction of light emitted from the side surfaces 33H and 33I by adjusting the inclination angles α and β of the side surfaces 33H and 33I of the optical members 30H and 30I. So it has the following advantages.
First, in addition to being able to spread light over a wide range in the lateral direction and emit the light, it is possible to more appropriately control the light distribution characteristics of the light emitted in the lateral direction.
Further, for example, by adjusting the inclination angles α and β of the side surfaces 33H and 33I of the optical members 30H and 30I at the final stage of the manufacturing process, various different light distribution characteristics can be realized, and the light emitting device having different light distribution characteristics. can be produced efficiently. As a result, it becomes possible to inexpensively provide a wide variety of light-emitting devices having different light distribution characteristics.

In the light emitting device of the sixth embodiment, the side surfaces 33H and 33I of the optical members 30H and 30I are inclined at the constant angles of inclination α and β. It may be configured by a curved surface, or may be configured by a side surface formed of a protruded or recessed curved surface instead of the side surfaces 33H and 33I. Even in this way, it is possible to control the light distribution characteristics of the light emitted in the horizontal direction.

The light emitting device of Embodiment 6 described above is configured in the same manner as the light emitting device of Embodiment 1 except that the side surfaces 33H and 33I of the optical members 30H and 30I are inclined at the constant angles of inclination α and β. However, in the light emitting device of Embodiment 6, the side surfaces 33H and 33I of the optical members 30H and 30I may be inclined at constant angles of inclination α and β in the light emitting devices of Embodiments 2 to 5, for example.

As can be understood from the above description, in the light emitting devices of Embodiments 1 to 6, by appropriately setting the angle or shape of the lower surface of the light reflecting portion and the surface direction of the side surface of the light transmitting portion, the light from the side surface of the light transmitting portion Light can be emitted in a desired direction. However, in the light-emitting devices of Embodiments 1 to 6, it is possible to further control the light distribution characteristics by controlling the surface roughness of the side surface of the light-transmitting portion. FIG. 12 schematically shows an example in which the surface roughness of the side surface 43 of the translucent portion 40 is increased in the light emitting device of the first embodiment. For example, if the surface roughness Ra of the side surface of the light transmitting portion is in the range of 0.1 to 50, and preferably in the range of 1 to 20, the scattering of light on the side surface of the light transmitting portion can be reduced. It can be made large, and the light distribution characteristic of the light emitted from the side surface of the light-transmitting portion can be made to have a spread. Here, the light distribution characteristic with a spread is realized by the angle of the lower surface of the light reflecting portion and the plane direction of the side surface of the light transmitting portion, and the light distribution when it is assumed that there is no scattering of light on the side surface of the light transmitting portion. It means that the attenuation rate of the intensity of light emitted in a direction different from the light distribution center is small compared to the light characteristics. In this way, if the light distribution characteristic of the light emitted from the side surface of the light-transmitting part is a spread light distribution characteristic, for example, when a plurality of light emitting devices are arranged in a matrix, the irradiation light is It becomes possible to uniformly irradiate light onto an object, and for example, a thinner backlight can be realized. Further, by increasing the surface roughness of the side surface of the light-transmitting portion, the total reflection on the side surface of the light-transmitting portion can be reduced, and the light extraction efficiency can be increased. Further, for example, if the surface roughness Ra of the side surface of the light-transmitting portion is set to a relatively small range of 0.001 to 0.1, preferably 0.005 to 0.05, the side surface of the light-transmitting portion light scattering can be reduced, and light is emitted based on the light distribution characteristics set by the angle or shape of the lower surface of the light reflecting portion and the surface direction of the side surface of the light transmitting portion. When the surface roughness Ra of the side surface of the light-transmitting portion is reduced, total reflection on the side surface of the light-transmitting portion tends to increase as the surface roughness Ra decreases. It is preferable to make it more than the lower limit of the said range.
As described above, in the light-emitting devices of Embodiments 1 to 6, by appropriately changing the surface roughness Ra of the side surface of the light-transmitting portion, the angle of the lower surface of the light-reflecting portion and the surface direction of the side surface of the light-transmitting portion It is possible to change the light distribution characteristics of the light emitted from the side surface of the translucent portion.
Therefore, for example, by appropriately changing the surface roughness Ra of the side surface of the light-transmitting portion at the final stage of the manufacturing process, various different light distribution characteristics can be realized, and light emitting devices having different light distribution characteristics can be efficiently manufactured. can do. As a result, it becomes possible to inexpensively provide a wide variety of light-emitting devices having different light distribution characteristics.
The surface roughness Ra of the side surface of the light-transmitting part is determined by polishing the side surface of the singulated light-emitting device to a desired surface roughness, or by the size and size of the abrasive grains of the cutting blade when singulating. / Or by appropriately selecting the rotation speed, the desired surface roughness can be easily adjusted.

100, 200, 300A, 300B, 400A, 400B, 400C, 400D, 400E, 600, 800 Light emitting device 101 Bottom surface of light emitting device 102 Top surface of light emitting device 103, 203, 303, 403, 803 Side surface of light emitting device DESCRIPTION OF SYMBOLS 10... Light emitting element 11... Laminated structure 11a... Electrode formation surface of laminated structure (light emitting element) 11b... Light emitting surface of laminated structure (light emitting element) 11c... Side surface of laminated structure (light emitting element) 12, 12p, 12n ... Electrode 20 ... Covering member 21 ... Lower surface (first surface) of covering member
22 ... Upper surface (second surface) of the covering member
23 Outer surface of coating member 24 Inner surface of coating member 30, 30A, 30B, 30C, 30D, 30E, 30F, 30G Optical member 31, 31C Lower surface of optical member (first surface)
32, 32D... Upper surface of optical member (second surface)
33 Side surface of optical member 34G Concave portion 40, 40A, 40B, 40C, 40D, 40E, 40F, 40G Translucent portion 41, 41F Lower surface of translucent portion (first surface)
41Fa... Recess on the lower surface of the translucent part 42... Upper surface of the translucent part (second surface)
43... Side surface of translucent part (light exit surface)
50, 50A, 50B, 50C, 50D, 50E, 50F, 50G... Light reflecting portion 50Ca, 50Ga... Convex portion of light reflecting portion 50Cb, 50Gb... Flat portion of light reflecting portion R... Top portion of light reflecting portion 51, 51A, 51B, 51C, 51G ... the lower surface (first surface) of the light reflecting portion
51Ca, 51Ga... Lower surface of convex portion of light reflecting portion 51Cb, 51Gb... Lower surface of flat portion of light reflecting portion 52, 52D... Upper surface of light reflecting portion (second surface)
53... Side surface of light reflecting part 54... Filling member 60, 60A, 60F, 60G... Light guide member 62, 62F, 62G... Upper surface of light guide member 63... Outer surface of light guide member 70, 70A, 70G... Wavelength conversion member 71, 71F, 71G... Lower surface (first surface) of wavelength conversion member
72, 72F, 72G... Upper surface (second surface) of wavelength conversion member
73, 73F, 73G... Side surface of wavelength conversion member 80... Metal layer _TO ... Thickness of optical member _TT1 ... Thickness at side surface of translucent part _TT2 ... Thickness at central part of translucent part _TR1 ... Side surface of reflecting part T _R2 : Thickness at the central portion of the reflective portion _WO : Width of the optical member _WD : Width of the light emitting element _WR1 : Width of the inclined portion of the reflective portion

Claims (10)

a semiconductor laminate including an electrode-formed surface, a light-emitting surface opposite to the electrode-formed surface, and a side surface between the electrode-formed surface and the light-emitting surface; and a pair of electrodes provided on the electrode-formed surface. a light emitting element provided;
a light-reflective covering member that covers the side surface of the light emitting element;
an optical member arranged over the light emitting surface of the light emitting element and the upper surface of the covering member;
a light guide member covering a side surface of the light emitting element and having an outer surface covered with the covering member;
a wavelength conversion member that covers the top surface of the light emitting element and the top surface of the light guide member and contains a phosphor;
with
The optical member includes a light reflecting portion disposed above the light emitting element, disposed between the light reflecting portion and the covering member, constitutes a part of an outer surface of the light emitting device, and contains a phosphor. and
The light reflecting portion includes a convex portion in the center and a planar portion around the convex portion,
the wavelength conversion member is in contact with the convex portion and the planar portion of the light reflecting portion;
The light-emitting device, wherein the side surface of the wavelength conversion member is covered with the translucent portion. 2. The light emitting device according to claim 1, wherein said light guide member covers 50% or more of the side surface of said light emitting element. 3. The light emitting device according to claim 1, wherein the light guide member covers the upper surface of the light emitting element. The light emitting device according to any one of claims 1 to 3, wherein the light guide member is directly or indirectly connected to the lower surface of the light transmitting portion. The light-emitting device according to any one of claims 1 to 4, wherein the translucent portion is not arranged above the wavelength conversion member. The light-emitting device according to any one of claims 1 to 5, wherein the entire upper surface of the wavelength conversion member is in contact with the light reflection section. 7. The method according to claim 5, wherein a plane area of the wavelength conversion member when viewed from above is larger than a plane area obtained by adding the plane area of the light emitting element and the plane area of the upper surface of the light guide member. luminous device. 7. The light-emitting device according to claim 5, wherein the side surface of said wavelength conversion member is a vertical surface. 7. The light-emitting device according to claim 5, wherein the side surface of said wavelength converting member is an inclined surface. 10. The light emitting device according to any one of claims 5 to 9, wherein a side surface of said wavelength converting member is spaced apart from a side surface of said light emitting device.

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