JP2021061444A - Light-emitting device - Google Patents

Abstract

To provide a light-emitting device capable of improving light-coupling efficiency from a light-emitting element to a light transmission member, having high luminous efficiency, and achieving high-luminance light emission.SOLUTION: A light-emitting device 100 is equipped with a light transmission member 20 that has a light-emitting surface and a light-receiving surface, a light-emitting element 10 that is equipped with an emission surface opposite to the light-receiving surface and is joined with the light transmission member, and a light-guiding member 30 that is provided so as to extend from a light-emitting element surface to a light transmission member surface, and guides emission light from the light-emitting element to the light transmission member. The light-guiding member has a joint area where the emission surface of the light-emitting element and a light-receiving surface of the light transmission member are opposed and joined with each other, and a first coating area where a surface of one of the light-emitting element and the light transmission member extended from the joint area and projected out from the joint area is coated. A first reflection surface reflecting the emission light to the light transmission member side is provided on an outer surface of the first coating area.SELECTED DRAWING: Figure 1

Description

The present invention relates to a light emitting device, and more particularly to a light emitting device including a light guide member for increasing luminous efficiency.

In recent years, light emitting devices equipped with semiconductor light emitting elements such as light emitting diodes (LEDs) and laser diodes (LDs) as light sources have been used in various lighting and display devices. In particular, since these semiconductor light emitting elements have low power consumption and long life, they are attracting attention as a light source for next-generation lighting that can replace fluorescent lamps, and further improvement in light emission output and light emission efficiency is required. In addition, a light source having good light distribution characteristics and high brightness, such as floodlights such as car headlights, is also required.

For example, in Patent Document 1, an LED chip assembly in which a phosphor chip is fixed to an LED chip with a light-transmitting adhesive is mounted on a cup portion of a lead frame or an insulating substrate, and is protected by mixing a light scatterer. A light emitting device in which the LED chip assembly is sealed with a layer or a sealing resin has been proposed.

JP-A-2002-141559 Japanese Unexamined Patent Publication No. 2007-019096 JP-A-2002-305328 Japanese Unexamined Patent Publication No. 10-151794 Japanese Unexamined Patent Publication No. 2009-043764 Japanese Unexamined Patent Publication No. 2008-300621 Japanese Unexamined Patent Publication No. 2008-277592

However, in the light emitting device described in Reference 1, the light-transmitting adhesive that adheres the phosphor chip to the LED chip directly from the phosphor chip or travels along the side surface of the light emitting element to the cup portion of the lead frame. And there is a risk of dripping to the insulating substrate, and the light emitted from the LED chip or phosphor chip is guided by the adhesive and absorbed by the surface of the insulating substrate or the electrodes or lead frames provided on it. As a result, there is a problem that the light output of the light emitting device is lowered, and there is a similar problem in the translucent resin that covers the light emitting element or the phosphor chip and the surface of the substrate, the electrode, or the like. Further, the optical path by such a translucent member is small, and even if it is narrow, it has a great influence on the characteristics of the light emitting device. Further, the LED chip and the phosphor chip of Reference 1 have only their facing surfaces fixed to each other by an adhesive, and the bonding efficiency of the light emitted from the LED chip to the phosphor chip is low. If the outer shape of the LED is poorly matched, there is a concern that the brightness unevenness, the color unevenness, and the directivity may deteriorate.

The present invention has been made in view of the above problems, and an object of the present invention is to reduce the loss of light emitted from a light emitting element to improve its utilization efficiency, and to improve the light coupling efficiency from the light emitting element to a light transmitting member. The purpose of the present invention is to provide a light emitting device capable of increasing light emission efficiency and brightness.

The light emitting device according to the present invention can achieve the above object by the following configurations (1) to (15).
(1) A light transmitting member having a light emitting surface and a light receiving surface of the light emitting device, a light emitting element provided with an emitting surface facing the light receiving surface and bonded to the light transmitting member, and the light transmitting from the surface of the light emitting element. The light guide member includes a light guide member extending to the surface of the member and guiding the light emitted from the light emitting element to the light transmitting member, and the light guide member includes the light emitting surface of the light emitting element and the light. A first that covers one surface of the light emitting element and the light transmitting member extending outward from the bonding region and extending from the bonding region to join the light receiving surfaces of the transmitting members so as to face each other. A light emitting device having a covering region of the above, and having a first reflecting surface for reflecting the emitted light toward the light transmitting member side on the outer surface of the first covering region.
(2) The light emitting device includes a coating member having a light reflecting material, and the coating member covers the surface of the light guide member and exposes the light emitting surface to cover the surfaces of the light emitting element and the light transmitting member. The light emitting device according to (1) above.
(3) The light emitting device according to (1) or (2) above, wherein the light transmitting member is a wavelength conversion member excited by the emitted light of the light emitting element.
(4) The first covering region covers the protruding surface of one of the light emitting element and the light transmitting member and the other side surface, and the first reflecting surface is provided so as to face the side surface. The light emitting device according to any one of (1) to (3) above.
(5) The covering member covers the other side surface of the other side surface via the light guide member of the first covering region, and covers the surface of the side surface of the light emitting element or the light transmitting member exposed from the light guide member. The light emitting device according to (4) above.
(6) A part of the light receiving surface of the light transmitting member projects outward from the emitting surface, and the first reflecting surface is an inclined surface inclined from the side surface of the light emitting element to the light receiving surface side. The light emitting device according to any one of (1) to (5).
(7) The light emitting device according to (6) above, wherein the light receiving surface of the light transmitting member is larger than the emitting surface of the light emitting element and includes the emitting surface.
(8) A part of the emitting surface of the light emitting element projects outward from the light receiving surface, and the first reflecting surface is an inclined surface inclined from the side surface of the light transmitting member toward the emitting surface side. The light emitting device according to any one of (1) to (5).
(9) The light emitting device according to (8) above, wherein the light emitting surface of the light emitting element is larger than the light receiving surface of the light transmitting member and includes the light receiving surface.
(10) The light emitting elements are separated from each other, and a plurality of the light emitting elements are joined to the light receiving surface side of the light transmitting member, and the light guide member is a part of the light receiving surface sandwiched between the separated light emitting elements. The second covering region has a second covering region extending from the bonding region and covering the light receiving surface side, and the second reflecting surface for reflecting the light emitted from the adjacent light emitting element toward the light receiving surface side is the second covering region. The light emitting device according to any one of (1) to (9) above, which is provided on the outer surface of the above.
(11) The light emitting device according to (10) above, wherein the second covering region covers the side surfaces of the separated light emitting elements facing each other.
(12) The light emitting device according to (10) or (11) above, wherein at least one set of the plurality of light emitting elements has different distances from the emitting surface to the light receiving surface of the light transmitting member.
(13) The light emitting element has a semiconductor layer and a substrate on the exit surface side of the semiconductor layer, and the light guide member extends to and covers the side surface of the substrate to expose the semiconductor side surface. The light emitting device according to any one of (1) to (12) above.
(14) The light emitting device includes the light reflecting material, exposes the light emitting surface, and includes the light emitting element and a covering member that covers a part of the light transmitting member, and the first reflecting surface or the first reflecting surface or The light emitting device according to any one of (1) to (13) above, wherein the second reflecting surface is provided at an interface between the light guide member and the covering member.
(15) The light emitting device according to any one of (1) to (14) above, wherein the first reflecting surface or the second reflecting surface is a convex curved surface that is convex toward the side surface.

According to the present invention, light is efficiently extracted from a light emitting element by joining a light transmitting member and a light emitting element arranged so as to face each other with a light guide member provided between the light transmitting member and a region extending from the light transmitting member. It is possible to provide a light emitting device that can guide light and lightly couple to a light transmitting member, has high luminous efficiency, and can emit light with high brightness. Further, the light transmitting member and the light emitting element joined by the light guide member are further covered with a light reflecting coating member to form a light emitting device having a light emitting surface as a part of the light transmitting member, thereby further improving efficiency. It is possible to provide a light emitting device capable of guiding light well, and when the light transmitting member is a wavelength conversion member, has light distribution characteristics with less color unevenness and high luminous efficiency, and is capable of high-luminance light emission. Further, with such a structure, the outer shape, size, and arrangement of the light emitting element and the light transmitting member can be made different, so that a light source having a desired shape and outer size can be obtained. It can be a light emitting device whose light emitting characteristics such as brightness can be adjusted.

It is a schematic top view (b) of the light emitting device which concerns on one Embodiment of this invention, and the schematic sectional view (a) in the AA cross section. It is schematic cross-sectional view explaining the periphery of the light source part of the light emitting device which concerns on one Embodiment of this invention. It is schematic cross-sectional view explaining the periphery of the light source part of the light emitting device of the comparative example which concerns on this invention. It is the schematic sectional drawing of the light emitting element which concerns on one Embodiment of this invention. It is a schematic sectional view (a) of the light emitting device which concerns on one Embodiment of this invention, and is a schematic sectional view (b) explaining the periphery of the light source part. It is schematic cross-sectional view explaining the periphery of the light source part of the light emitting device which concerns on one Embodiment of this invention. It is schematic cross-sectional view for demonstrating the periphery of the light source part of the light emitting device which concerns on one Embodiment of this invention. It is schematic cross-sectional view explaining the light emitting device which concerns on one Embodiment of this invention. It is schematic cross-sectional view explaining the light emitting device which concerns on one Embodiment of this invention.

Hereinafter, embodiments of the invention will be described with reference to the drawings as appropriate. However, the light emitting elements / devices described below are for embodying the technical idea of the present invention, and do not specify the present invention as the following. In particular, the dimensions, materials, shapes, relative arrangements, etc. of the components described below are not intended to limit the scope of the present invention to that alone, but are merely explanatory examples unless otherwise specified. Only. The size and positional relationship of the members shown in each drawing may be exaggerated to clarify the explanation. Further, each element constituting the present invention may be configured such that a plurality of elements are composed of the same member and the plurality of elements are combined with one member, or conversely, the function of one member is performed by the plurality of members. It can also be shared and realized. Similarly, with respect to each of the embodiments described below, each configuration and the like can be appropriately combined and applied unless otherwise specified.

As shown in FIGS. 1 and 2, the light emitting device of the present invention is mainly composed of a light emitting element 10, a light transmitting member 20, and a light guide member 30. The light emitting element 10 has an emitting surface, and the light transmitting member 20 has a surface 21 (light emitting surface 90) exposed to the outside, a light receiving surface 22 facing the surface 21, and a side surface, respectively. The light emitting element 10 is arranged so that its emitting surface faces the light receiving surface 22 of the light transmitting member, and one member of the light emitting element 10 and the light transmitting member 20 is projected outward from the other member. An adhesive that fixes the light emitting element 10 and the light transmitting member 20 can be applied to the light guide member 30, and the light transmitting member 30 has light transmittance and transmits light from the surface of the light emitting element and the light transmitting member, specifically, the surface of the light transmitting element. It is provided so as to extend to the surface of the member and has a function of guiding the emitted light of the light emitting element 10 to the light transmitting member 20. The light guide member 30 has a joint region 31 that joins an exit surface of a light emitting element facing each other and a light receiving surface 22 of a light transmitting member, and a protruding surface (emission of the light emitting element) extending from the joint region. It has a covering region (32, 37) that covers a surface or a part of a light receiving surface 22 of the light transmitting member. The light guide member is separated from the mounting surface of the substrate, recedes from the mounting side surface of the light emitting element 10, and is located on the light transmitting member 20 side. Therefore, it is possible to prevent the light emitted from the light emitting element 10 from propagating through the light guide member 30 and being guided to the substrate 50 and being absorbed. The outer surface of the covering region is provided with a reflecting surface that reflects the light emitted from the light emitting element 10 toward the light transmitting member 20 side. In this way, the reflection of the outer surface of the light guide member 30 suppresses the diffusion of light, and the light can be focused in the light guide member 30 to guide the light to the light transmitting member 20, and the light loss due to absorption. The light emitted from the light emitting element 10 can be efficiently combined with the light transmitting member 20, and the brightness distribution of the light emitting surface can be improved. Further, by joining the light emitting element and the light conversion member, the brightness and chromaticity in the light emitting surface can be made a good distribution.

Further, as shown in FIGS. 1, 2, 5 and 6, this covering region is covered so as to connect the surface of the protrusion and the other side surface, and the light guide member faces the covered side surface. It is preferable that the reflective surface is provided on the outer surface of the above. By using the inclined surface connecting the surface of one protruding portion and the other side surface as the outer surface, the bulge to the outside of the covering region is suppressed, and up to the light transmitting member 20 of the light reflected by the outer surface. By shortening the optical path length of the light path and making the outer surface a concave curved surface, it becomes a reflecting surface of a convex curved surface, and the light guiding function of the light guide member 30 can be enhanced.

Further, as shown in FIGS. 1 and 2, the light emitting device of the present invention further includes a light-reflecting coating member 40, and a part of the light emitting element 10 and the light transmitting member 20 is covered with the coating member 40. The exposed surface 21 of the light transmitting member can be used as the light emitting surface 90 of the device, and can also be a surface light emitting device. The covering member 40 also functions as a filler and a sealing material containing the light-reflecting material 45, and the light emitting device can be miniaturized. Further, by covering the surface of the light guide member 30 with its light reflectivity, the light guide action can be assisted and the light coupling efficiency of the light emitted from the light emitting element 10 to the light transmitting member can be further enhanced. it can. Further, on the surface of the light emitting element and the light transmitting member, a region covered with the light guide member and a region exposed from the region are provided, and the region is covered with the covering member, that is, the exposed region is directly formed. It is preferable that the covering region is covered with the covering member via the light guide member. Specifically, the covering member covers one side surface in the covering region via the light guide member 30, and covers the other side surface exposed from the light guide member 30. As a result, the light reflection function of the covering member enhances the light confinement action in the light guide member 30 in the covering region, and limits the light propagation region from the light emitting element 10 to the light transmitting member 20 in the exposed region. Therefore, the light guide member 30 can efficiently guide the light to the light transmitting member 20. Further, it is preferable that the reflective surface of the covering region is provided at the interface between the light guide member and the covering member, so that its function can be further enhanced. With such a configuration, it is possible to improve the utilization efficiency of the light emitted from the light emitting element 10 and realize high-luminance light emission with less color unevenness and excellent light distribution characteristics.

(Embodiment 1)
1 and 2 are a light emitting device 100 according to the first embodiment of the present invention, and the cross section of FIG. 1 (a) is a schematic cross-sectional view taken along the line AA of FIG. 1 (b) on the schematic upper surface. 2 is a schematic cross-sectional view around the light source portion. The light emitting device 100 of the example shown in FIG. 1 is a surface light emitting device having a light emitting surface 90. The light emitting device 100 mainly has a plate-shaped light having a light emitting element 10 having a semiconductor element structure 11 on a growth substrate 1 and a surface 21 to be a light emitting surface 90 exposed and having a light receiving surface 22 facing the surface 21. It is composed of a transmitting member 20, a light guide member 30 that guides the emitted light of the light emitting element 10 to the light transmitting member 20, and a coating member 40 containing a light reflecting material 45. The light emitting element 10 is flip-chip mounted on the wiring layer 51 of the substrate 50 with the emission surface, which is the back surface of the growth substrate 1, facing the light receiving surface 22 of the light transmitting member, and is mounted on the wiring layer 51 of the substrate 50 by the intervening light guide member 30. It is optically coupled to the light transmitting member 20. A frame 55 surrounding the light emitting element 10 and the light transmitting member 20 is provided on the substrate 50, and a covering member 40 is filled inside the frame body 55, and the light emitting element 10 and a part of the light transmitting member 20 are covered. It is covered with a member 40. The light emitting region of the light emitting device 100, that is, the window portion for emitting light is substantially limited to the surface 21 of the light transmitting member 20, and the surface emitting device is a surface emitting type light emitting device having the surface 21 as the light emitting surface 90. Further, the light emitting device 100 can control the brightness of the light emitted from the surface 21, that is, the light emitting surface 90, and the distribution of the light distribution, depending on the shape and size of the surface 21 of the light transmitting member 20. Further, the light emitting device has a relatively uniform brightness and chromaticity in the light emitting surface. Here, the planar shapes of the light transmitting member and the light emitting element are rectangular as shown in the drawing, and the light emitting element is included in the light transmitting member in a plane.

When the light source portion thereof is described in detail with reference to FIG. 2, the light guide member 30 has a bonding region 31 for joining the light emitting element 10 and the light transmitting member 20 so as to face each other, and more specifically, the light transmitting member 30 has a bonding region 31. The light receiving surface 22 of the member is provided in a region facing the exit surface of the light emitting element 10. In a specific example, for example, an example described later, the thickness of this bonding region is about 0.01 μm to 100 μm. By interposing the light guide member 30 at the junction region, the light emitting element and the light transmitting member are separated from each other, and the difference in refractive index on the emission surface of the light emitting element 10 is relaxed as compared with the case where a gas such as atmosphere is present. , Light can be efficiently extracted from the light emitting element 10. Therefore, the light from the light emitting surface of the light emitting element 10 is transmitted into the bonding region 31 and is directly photocoupled to the light receiving surface 22 of the light transmitting member.

In the present embodiment, the light receiving surface 22 of the light transmitting member is larger than the emitting surface of the light emitting element 10, and includes the light receiving surface 22 so that a part of the light receiving surface 22 projects outward from the emitting surface of the light emitting element 10. In other words, the side surface of the light transmitting member 20 is located outside the side surface of the light emitting element 10, and a protrusion is provided on the entire peripheral edge thereof. In such a light emitting device 100, the luminous flux of the emitted light can be increased by using the light emitting surface 90 of the light emitting device as a window portion for emitting light that is relatively larger than the emitting surface of the element. Then, the light guide member 30 extends from the above-mentioned joining region 31 and covers the protruding surface of the light transmitting member and the side surface hanging on a part of the side surface of the light emitting element 10. Specifically, this region is provided in a region protruding outward from the joint region. Here, since the light emitted from the light emitting element 10 is usually emitted not only from the emitting surface but also from the side surface and the bottom surface side (mounting surface side), a part of the light is mainly from the side surface of the light emitting element. It is incident on the covering region 32 of the above and is guided. That is, as in the case of the above-mentioned bonding region, the difference in the refractive index of the radiation surface of the light emitting element can be alleviated and the light extraction efficiency can be increased in the first covering region 32 as well. Here, the outer surface of the first covering region 32 facing the covering member 40 side, that is, the outer surface facing the side surface of the light emitting element 10 of the first covering region 32 transmits the emitted light of the light emitting element 10. It has a first reflecting surface 33 that is reflected to the member 20 side, and therefore the reflected light of the emitted light is reflected by the first reflecting surface 33 to the light receiving surface 22 side of the light transmitting member 20 and guided. It is lightly coupled to the light transmitting member 20. In this way, the light emitted from the light emitting element 10 to the side is once taken out into the light guide member 30 and then reflected by the first reflecting surface 33, so that the light is exposed from the light guide member and the light emitting element 10 is light-reflected. Compared with the form of directly covering with the property covering member 40, the loss of light due to absorption in the light emitting element 10 can be reduced, and the light once propagates and spreads in the light guide member, so that the light coupling efficiency and the light coupling efficiency can be improved. The light emission characteristics can be improved.

As described above, as shown in FIGS. 1 and 2 as in the present embodiment, the reflection function can be enhanced by providing the first reflection surface 33 of the light guide member 30 at the interface with the covering member 40. Further, since the interface is composed of the translucent light guide member 30 and the coating member 40 containing a light-reflecting material in the translucent base material, the interface is a gentle reflective interface that seeps into the coating member. Become. Such a configuration can be easily formed by forming the first covering region 32 in the light guide member 30 and then filling the covering member 40, and is a structure excellent in mass productivity. The first reflecting surface 33 does not necessarily have to be provided at the interface with the covering member 40. For example, the outer surface of the first covering region 32 facing the covering member 40 side and the covering member 40 are separated from each other, a gap is provided between them, and the first reflecting surface 33 is the interface between the light guide member 30 and air. It may be in the form provided in. According to this form, the light guide member 30 side has a high refractive index at this interface, and a large amount of light can be reflected in the first covering region 32. Further, the light component transmitted from the first covering region 32 into the void can also be reflected again on the surface of the covering member 40. In addition to this form, for example, a highly reflective metal film such as silver (Ag) or aluminum (Al), a dielectric multilayer film, or a layer made of translucent particles is provided on the outer surface of the first covering region 32. The first reflecting surface 33 may be formed.

Further, in the light emitting device 100, the surface of the first covering region 32 facing the side surface of the light emitting element 10 is preferably an inclined surface inclined from the side surface toward the light receiving surface 22 side of the light transmitting member. As a result, the light emitted laterally from the light emitting element 10 can be satisfactorily reflected toward the light receiving surface 22 side of the light transmitting member, and the cross-sectional width widens toward the protruding surface, so that good optical coupling is achieved. it can. Further, although the inclined surface may be a flat surface, the surface area of the first reflecting surface 33 can be increased as compared with the case where the inclined surface is a flat surface by having a convex curved surface convex toward the joint region 31, and the light can be increased. It is preferable because the reflection efficiency of the light can be increased.

The method for forming the first covering region 32 is not particularly limited, but is formed by, for example, applying an appropriate amount of the resin material constituting the light guide member 30 on the exit surface of the light emitting element 10 and then mounting the light transmitting member 20. can do. At this time, the light transmitting member 20 may be pressed appropriately. The resin is applied by a dispensing method, a stamping method, or the like, and the light transmitting member 20 can be mass-produced by a die bonding apparatus equipped with a collet capable of adsorbing, transporting, and pressing the light transmitting member 20.

The resin material constituting the light guide member 30 may drip directly from the projecting portion of the light emitting element 10 or the light transmitting member 20 or along the side surface of the light emitting element 10 and reach the mounting substrate 50. FIG. 3 is a schematic cross-sectional view for explaining a mode in which a hanging portion is provided on such a light guide member 36. In this embodiment compared with the present invention, as shown in FIG. 3, when the adhesive resin of the light guide member 36 continuously hangs down on the mounting substrate 50 along the side surface of the light emitting element 10, light is emitted at the hanging portion thereof. A route is formed. Therefore, the light emitted laterally or downward from the light emitting element 10 is guided to the mounting substrate 50 side by the hanging portion and reaches the surface of the mounting substrate 50 or the wiring 51, resulting in light loss due to absorption. Occurs. Further, the formation of the hanging portion may block the formation of the underfill 70 or the like in the region between the light emitting element 10 and the substrate 50 and the infiltration of the covering member 40, and when the hollowing thereof causes light to leak. Light loss occurs. In particular, if the amount of the resin material applied is too large, the light guide member 36 may hang directly on the substrate 50 from the protruding portion of the light transmitting member 20, or may be separated from the bonding region and crosslinked with the light emitting element 10 and the substrate 50. Even so, an optical path is formed in the same manner as described above, which may lead to optical loss. Further, in the third embodiment described later, as compared with the case where the light transmitting member protrudes as in the present embodiment, the hanging portion which covers the side surface and reaches the mounting substrate in the same manner as the structure which is difficult to form. Can be provided. Therefore, the amount of the resin material applied is appropriately adjusted so as not to be excessive, and the area of the protruding surface and the position of the protruding portion are adjusted as described later.

Therefore, the outer surface of the first covering region 32 is preferably located on the light transmitting member 20 side of the bottom surface and the mounting surface of the light emitting element 10, and the range covered by the first covering region 32 is light emitting. It is preferable that the element 10 is halfway on the side surface. That is, as shown in FIGS. 1 and 2, on the side surface of the light emitting element 10, the region (first coated region 32) covered on the exit surface (upper side) side with respect to the light guide member, the bottom surface, and the mounting surface. It is desirable that an exposed area is provided on the (lower) side. Further, it is preferable that this exposed region is covered with the covering member 40. More specifically, when the light emitting element 10 has a semiconductor layer 11 having an element structure and a substrate 1 on the exit surface side of the semiconductor layer, the light guide member 30 extends to the side surface of the substrate and covers it. It is preferable that the side surface of the semiconductor layer 11 is exposed. As a result, the light reflectivity on the semiconductor layer 11 side including the light emitting layer can be enhanced, while the light transmissivity on the substrate side can be enhanced. Further, the first covering region 32 may be formed so as to extend uniformly from the junction region 31 to the side surface of the light emitting element 10, but discretely or partially from the junction region 31 to the side surface of the light emitting element 10. It may be formed by hanging down.

Such a form can be easily achieved by subjecting a region to be exposed from the light guide member 30 to a surface treatment such as applying a mold release agent in advance to make it difficult for the region to be covered with the light guide member 30 or the like. As the release agent, a commercially available one can be used, and for example, a fluorine-based release agent such as a spray type die-free or a chemical solution type optool manufactured by Daikin Corporation can be used. In particular, it is preferable that the surface facing the exit surface and the mounting surface of the light emitting element 10 are surface-treated, and further, a part of the side surface continuous from the surface, particularly the side surface of the semiconductor layer 11, that is, the exposure of the semiconductor layer 11. It is preferable that the surface is surface-treated. Further, the surface treatment and the covering member 40 do not have to be in agreement with each other, and may partially overlap or be separated from each other.

On the other hand, in the light emitting device 100 of the example shown in FIGS. 1 and 2, it is preferable that the side surface of the light transmitting member 20 is exposed from the light guide member 30 and further covered with the light reflecting covering member 40. In this way, as compared with the case where the light guide member 30 also covers the side surface of the light transmitting member 20, the outward bulge of the outer surface of the light guide member 30 can be suppressed, and therefore the optical path length to the light transmitting member 20 is shortened. It can improve the optical coupling efficiency. Further, as described above, it is preferable to easily form the first reflecting surface 33 having a shape and an inclination angle suitable for light reflection toward the light receiving surface 22 side.

Next, each component and structure of the light emitting device of the present invention will be described in detail below.

(Light emitting element)
As the light emitting element 10, a known one, specifically, a semiconductor light emitting element can be used, and in particular, a GaN-based compound semiconductor is preferable because it can emit short-wavelength visible light or ultraviolet light capable of efficiently exciting a fluorescent substance. .. The specific emission peak wavelength is 240 nm or more and 560 nm or less, preferably 380 nm or more and 470 nm or less. In addition, a ZnSe-based, InGaAs-based, or AlInGaP-based semiconductor light-emitting element may be used.

(Light emitting element structure)
As illustrated in FIG. 4, the light emitting device structure 11 made of a semiconductor layer is composed of at least a first conductive type (n type) layer 2 and a second conductive type (p type) layer 3, and an active layer 3 is further formed between them. The structure having is preferable. Further, the electrode structure is preferably the same surface side electrode structure in which both the first conductive type (negative) and the second conductive type (positive) electrodes 6 and 7 are provided on one main surface side, but each main surface of the semiconductor layer. A counter electrode structure in which electrodes are provided so as to face each other may be used. As for the mounting form of the light emitting element 10, for example, in the same surface side electrode structure, the flip chip mounting in which the electrode forming surface is the mounting surface and the substrate 1 side facing the electrode forming surface is the main emitting surface is the emitting surface and the light transmitting member. It is preferable in terms of optical connection with 20. In addition, mounting with the electrode forming surface side as the main emission surface and connecting a light transmitting member on it, face-up mounting, flip chip mounting on a light transmitting member having a wiring structure, and light transmission by the counter electrode structure. It is possible to connect the member to the mounting substrate, and it is preferable to mount the embodiment in which the light emitting element and the light transmitting member are not provided with wiring or electrodes. The growth substrate 1 of the semiconductor layer 11 may be removed when the light emitting element structure is not formed, and a support substrate, for example, a conductive substrate or another translucent member may be removed from the semiconductor layer from which the growth substrate has been removed. -It is also possible to have a structure in which a substrate is bonded. A light transmitting member 20 can be used for this support substrate, and an element having a structure in which a semiconductor layer is adhered and coated with a light transmitting member such as glass or resin may be used. Removal of the growth substrate can be carried out, for example, by mounting or holding on a support, device or submount, peeling, polishing, or LLO (Laser Lift Off). Further, the light emitting element 10 can have a light reflection structure, and specifically, of the two main surfaces of the semiconductor layer 11 facing each other, the other main surface facing the light extraction side (emission surface side) is used. A light-reflecting structure can be provided in the semiconductor layer or electrodes on the light-reflecting side on the light-reflecting side (lower side in FIG. 1). As an example of the light-reflecting structure, a structure in which a multilayer reflective layer is provided in the semiconductor layer, or an electrode or a reflective layer having a metal film having high light reflectivity such as Ag or Al or a dielectric multilayer film is provided on the semiconductor layer. There is a structure.

(Nitride semiconductor light emitting device)
As an example of the light emitting element 10, in the nitride semiconductor light emitting element 10 of FIG. 4, the n-type semiconductor layer and the active layer 3 which are the first nitride semiconductor layers 2 are placed on the C-plane sapphire substrate which is the growth substrate 1. The light emitting layer and the p-type semiconductor layer, which is the second nitride semiconductor layer 4, are epitaxially grown in this order. Then, a part of the n-type layer 2 is exposed to form the n-type pad electrode which is the first electrode 7, and the translucent conductive layer 5 such as ITO and the second electrode cover almost the entire surface of the p-type layer 4. A p-type pad electrode of No. 6 is formed. Further, the protective film 8 is provided by exposing the surfaces of the n-type and p-type pad electrodes 6 and 7 and covering the semiconductor layer. The n-type pad electrode 7 may be formed via a translucent conductive layer as in the p-type. The growth substrate 1 includes C-plane sapphire, R-plane and A-plane, _{an insulating substrate such as spinel (MgAl 2} O ₄ ), silicon carbide (6H, 4H, 3C), Si, ZnS, ZnO, and GaAs. , GaN, AlN and other semiconductor conductive substrates. As an example of the nitride semiconductor, in addition to the general formula In _x Al _y Ga _1-x-y N (0 ≦ x, 0 ≦ y, x + y ≦ 1), B, P, and As may be mixed. .. The n-type and p-type semiconductor layers 2 and 4 are not particularly limited to a single layer or a multilayer, and the active layer 3 is preferably a single layer (SQW) or a multiple quantum well structure (MQW). As an example of the element structure 11 that emits blue light, an n-type semiconductor layer, for example, Si-doped GaN, is formed on a sapphire substrate via a base layer of a nitride semiconductor such as a buffer layer, for example, a low-temperature growth thin film GaN and a GaN layer. The n-type contact layer and the n-type multilayer film layer of GaN / InGaN are laminated, followed by the MQW active layer of InGaN / GaN, and further, as the p-type semiconductor layer, for example, the p-type multilayer film layer of Mg-doped InGaN / AlGaN. There is a structure in which a p-type contact layer of Mg-doped GaN is laminated.

(Light transmitting member)
Further, the light emitting device 100 of FIG. 1 includes a light transmitting member 20 that transmits light from the light emitting element 10. The light transmitting member 20 is preferably a light conversion member having a wavelength conversion material capable of wavelength-converting at least a part of the passing light. For example, as in the embodiment, the primary light from the light source excites the phosphor as the wavelength conversion material in the light transmitting member 20, so that the secondary light having a wavelength different from that of the primary light is obtained, and further, the primary light is obtained. By mixing the color with light, it is possible to realize an emitted light having a desired hue.

As described above, the light transmitting member 20 of the first embodiment includes the light emitting element 10 in a plan view from the surface 21 (light emitting surface 90), and the side surface thereof is outward from the side surface (end surface) of the light emitting element 10. The light receiving surface 22 is wider than the emitting surface of the light emitting element 10 and is optically connected via the light guide member, so that the loss is small. The protruding length of the side surface of the light transmitting member with respect to the side surface of the light emitting element is, for example, 0.25 times or more and 5 times or less, specifically 0.5 times or more and 2 times, as compared with the thickness of the light emitting element. It is less than double. As an example, in the light emitting device of the first embodiment, the light emitting device has a width of about 50 μm protruding from the end of the light transmitting member 20. In addition, as shown in the third embodiment described later, the side surface of the light transmitting member may be located inside the side surface of the light emitting element, that is, the emitting surface of the light emitting element may protrude, as in this example. The light receiving surface 22 of the light transmitting member may be smaller than the emitting surface of the light emitting element 10. In this form, the protruding length is, for example, 0.25 times or more and 5 times or less, specifically 0.5 times or more and 2 times or less, as compared with the thickness of the light transmitting member. By narrowing the light emitting region with respect to the light emitting element, the brightness is relatively increased, the color mixing can be made uniform, and the color unevenness is reduced. Further, if the side surface of the light transmitting member 20 is located on substantially the same surface as the side surface of the light emitting element 10, the amount of light from the light emitting element 10 is insufficient at the outer edge of the light transmitting member 10 and color unevenness occurs. It can be suppressed from becoming easy.

Here, as the translucent material serving as the base material of the light transmitting member 20, the same material as the following covering member 40 can be used, and for example, an inorganic substance such as resin or glass can be used. Even when the conversion function is not provided, it is preferable to use the same material as the light transmitting member for light conversion by removing or substituting the phosphor. Further, when the light transmitting member is plate-shaped as in the embodiment, the surface 21 and the light receiving surface 22 are both substantially flat surfaces, and the opposing surfaces are substantially parallel to each other. It is preferable that the efficiency of optical coupling via the light guide member of the present invention is increased and the bonding is facilitated. On the other hand, it is not limited to a plate shape, but various shapes or forms such as a shape having a curved surface in whole or a part, a planar shape such as an uneven surface, for example, a shape for condensing and dispersing, for example, a lens shape, etc. It can also have an optical shape such as. Further, as a wavelength conversion function, in addition to emitting mixed color light of the primary light of the light emitting element and its converted light (secondary light), for example, conversion light by ultraviolet light of the light emitting element or mixed color light by a plurality of converted lights. In addition, it can also be a light emitting device that mainly emits secondary light converted from primary light.

The light transmitting member 20 having a wavelength conversion function is specifically a glass plate, a member provided with the light conversion member, or a phosphor crystal of the light conversion member or a monocrystal, a polycrystal, or an amorphous body having a phase thereof. , Ceramic body, or a sintered body of a translucent material added appropriately by a ceramic body or a fluorescent material, an aggregate, a porous material, and a translucent material, for example, a translucent resin, mixed and impregnated therein. It is composed of a light-transmitting member or a light-transmitting member containing phosphor particles, for example, a molded body of a light-transmitting resin. From the viewpoint of heat resistance, it is preferable that the light transmitting member 20 is made of an inorganic material rather than an organic material such as a resin. Specifically, it is preferably made of a translucent inorganic material containing a fluorescent substance, and in particular, a sintered body of a fluorescent substance and an inorganic substance (binding material, a binder), or a sintered body or a crystal made of a fluorescent substance. This increases reliability. When the YAG phosphor of the example is used, in addition to a single crystal of YAG and a high-purity sintered body, _{a YAG / alumina sintered body using alumina (Al 2} O ₃ ) as a binder and glass are bonded. A sintered body used as a material is preferable from the viewpoint of reliability. Further, by making the light transmitting member 20 plate-shaped, the coupling efficiency with the emitting surface of the light emitting element 10 formed in a planar shape is good, and the position is easily positioned so as to be substantially parallel to the main surface of the light transmitting member 20. Can be matched. In addition, by making the thickness of the light transmitting member 20 substantially constant, the wavelength conversion amount of the passing light can be made substantially uniform, the mixing ratio can be stabilized, and color unevenness at the portion of the light emitting surface 90 can be suppressed. Therefore, when a plurality of light emitting elements 10 are mounted on one light transmitting member 20, the distribution of brightness and chromaticity in the light emitting surface 90 due to the arrangement of the individual light emitting elements 10 is not uneven and is substantially uniform and high. Luminance emission can be obtained. The thickness of the light transmitting member 20 having a wavelength conversion function is preferably 10 μm or more and 500 μm or less, and more preferably 50 μm or more and 300 μm or less in terms of luminous efficiency and chromaticity adjustment.

The wavelength conversion member can be preferably combined with a blue light emitting element to emit white light, and a typical phosphor used for the wavelength conversion member is a YAG-based phosphor (yttrium, aluminum, etc.) enclosed in cerium having a garnet structure. garnet) and LAG-based phosphor (lutetium aluminum garnet) can be mentioned, in particular, at the time of high luminance and long-term use _{(Re 1-x Sm x)} 3 (Al 1-y Ga y) 5 O 12 : Ce (0 ≦ x <1, 0 ≦ y ≦ 1, where Re is at least one element selected from the group consisting of Y, Gd, La, and Lu) and the like are preferable. Further, a phosphor containing at least one selected from the group consisting of YAG, LAG, BAM, BAM: Mn, (Zn, Cd) Zn: Cu, CCA, SCA, SCESN, SESN, CESN, CASBN and CaAlSiN _{3: Eu.} Can be used. In addition to the light transmitting member, the wavelength conversion member may be provided, for example, between the light transmitting member and the light emitting element, in the coupling member thereof, and between the light emitting element and the covering member. Similarly, the light transmitting member, the wavelength conversion member, and the sintered body can be arranged in the light emitting device. It is also possible to increase the reddish component by using a nitride-based phosphor or the like having yellow to red light emission, and to realize illumination having a high average color rendering index Ra, a light bulb color LED, or the like. Specifically, by adjusting and containing the amount of phosphors having different chromaticity points on the CIE chromaticity diagram according to the emission wavelength of the light emitting element, the phosphors and the chromaticity diagram connected by the light emitting element are connected. Any point of can be made to emit light. In addition, a nitride phosphor, an oxynitride phosphor, and a silicate phosphor that convert near-ultraviolet to visible light into a yellow to red region can be used. For example, L ₂ SiO ₄ : Eu (L is an alkaline earth metal), in particular (Sr _x Mae _1-x ) ₂ SiO ₄ : Eu (Mae is an alkaline earth metal such as Ca, Ba) and the like can be mentioned. Nitride-based phosphors and oxynitride (oxynitride) phosphors include Sr-Ca-Si-N: Eu, Ca-Si-N: Eu, Sr-Si-N: Eu, and Sr-Ca-Si. -O-N: Eu, Ca-Si-ON: Eu, Sr-Si-ON: Eu, etc. As an alkaline earth silicon nitride phosphor, the general formula LSi ₂ O ₂ N ₂ : Eu , General formula L _{x S y} N _{(2 / 3x + 4 / 3y)} : Eu or L _{x S y} O _z N _{(2 / 3x + 4 / 3y-2 / 3z)} : Eu (L is Sr, Ca, Sr and Ca It is represented by either).

(Coating member)
As shown in FIG. 1, the covering member 40 covers a part of the light transmitting member 20, specifically, at least a part of the side surface of the light transmitting member 20. In the present invention, the covering member is hung from the element or the like to prevent the formation of a light leakage path. Therefore, it is preferable that the covering member has a higher reflectance than the substrate and the wiring provided therein. The base material of the coating member 40 containing the light-reflecting material is preferably a translucent resin material, and a silicone resin composition, a modified silicone resin composition, or the like is preferably used. A translucent insulating resin composition such as a modified epoxy resin composition or an acrylic resin composition can be used. Further, a covering member having excellent weather resistance, such as a hybrid resin containing at least one of these resins, can also be used. Further, an inorganic substance having excellent light resistance such as glass and silica gel can also be used. Further, by molding the resin material, it can be molded into a desired shape and can cover a desired region. In the present invention, the surface of the light emitting element, the light guide member, and the light transmitting member of the light source portion, particularly the side surface thereof is coated. Can be formed. Further, the surface on the light emitting surface side can be similarly formed into a desired shape, and can be a concave or convex curved surface in addition to a flat surface as shown in the figure. In the first embodiment, a silicone resin is used as a coating member from the viewpoint of heat resistance and weather resistance.

Further, the covering member 40 contains at least one kind of light-reflecting material 45 in the base material. By containing the light-reflecting material 45, the reflectance of the covering member 40 is increased, and more preferably, when low-absorbing particles are used, light absorption and loss are reduced, and the covering member has light scattering property. it can. The light-reflecting material 45 contained in the coating member 40 is one kind of oxide selected from the group consisting of Ti, Zr, Nb, Al, and Si, or at least one kind of AlN and MgF, and is specifically. Is at least one selected from the group consisting of TiO ₂ , ZrO ₂ , Nb ₂ O ₅ , Al ₂ O ₃ , MgF, Al N, and SiO _2. Since the particles of the light-reflecting material are one kind of oxide selected from the group consisting of Ti, Zr, Nb, and Al, the material can have high reflectivity and low absorbency, and the base material, particularly light-transmitting material, can be obtained. It is preferable because the difference in refractive index from the sex resin can be increased. Further, the covering member 40 can be formed of a molded body made of the light-reflecting material, and specifically, can be made of a porous material such as an agglomerate or a sintered body in which the particles are aggregated. In addition, a molded product obtained by a sol-gel method may be used, which is preferable because the difference in refractive index between the light-reflecting material and the air in the porous material can be increased, the light reflectivity can be enhanced, and the material can be composed of an inorganic material. .. On the other hand, as compared with a covering member provided with a base material such as the above resin, it is possible to form a desired shape, have better controllability of the covering region, and improve sealing performance and airtightness. Then, it is preferable to use a covering member provided with the above base material. Further, in consideration of the characteristics of both covering members, a composite molded body of both can be obtained. For example, the outer surface side of the porous molded body is impregnated with resin, and the inner surface side of the light emitting element side is porous. The structure can be made. As described above, the covering member or the surrounding body formed by the covering member may be in a form in which the inner region and the outer region are communicated with each other or the outer region is gas-permeable, and at least the light does not leak out.

In the coating member 40 containing the light-reflecting material 45 in the base material described above, the depth at which light leaks differs depending on the concentration and density thereof. Therefore, the concentration and density are appropriately adjusted according to the shape and size of the light emitting device. You should adjust it. For example, when the wall thickness is reduced with a relatively small light emitting device, it is preferable to provide a high-concentration light-reflecting material 45. On the other hand, in the manufacturing process such as preparation of the raw material of the coating member 40 containing the light-reflecting material 45, coating of the raw material, and molding, the concentration is adjusted so as to be suitable for it. The same applies to the above-mentioned porous body. As an example, in the case of Examples, it is preferable that the content concentration of the light-reflecting material 45 is 20% by weight (wt%) or more, and the wall thickness thereof is 20 μm or more, and the light emitting surface 90 has high brightness. Emitted light with high directivity can be obtained, and underfill can be easily formed by the covering member with an appropriate viscosity. Further, if the concentration of the light-reflecting material is increased, the thermal diffusivity of the covering member can be enhanced.

In the forming region of the covering member, the covering member 40 is provided on at least the side surface of the light transmitting member 20, preferably the side surface of the light emitting element is also covered, and more preferably, the light emitting surface is exposed in the light source portion including the light transmitting member and the light emitting element. The same applies to the case where the light source member 30 is used to cover the other material. As a result, it is possible to prevent light from leaking from the side surface of the light transmitting member, and when a light conversion member is provided, light having a relatively high intensity from the side surface and having a color difference is suppressed to suppress synchrotron radiation. The directivity can be improved and uneven brightness and uneven color can be reduced. Further, by covering the side surfaces of each member and the element and limiting the light extraction direction side, the directivity and the brightness can be enhanced. Further, when the light transmitting member 20 contains a wavelength conversion material, the heat generation of the wavelength conversion material is particularly remarkable, which can be improved. As long as the side surface of the light transmitting member 20 is covered with the covering member 40 and the surface 21 is exposed, the outer surface shape thereof is not particularly limited, and as shown in FIG. 1, the exposed surface is larger than the surface 21 of the light transmitting member. It may have a recessed structure. By projecting the light emitting surface 90, it is possible to avoid shading by the covering member 40, and the surface may be substantially the same surface, and a desired surface can be obtained. In the first embodiment, the covering member 40 also covers a part of the light receiving surface 22, and as shown in the drawing, the periphery of the light emitting element 10 is specifically a region facing the light emitting element 10 on the light receiving surface 22 of the light transmitting member. Cover the area excluding. With this configuration, as seen in FIG. 2, the light receiving surface 22 is provided with an optical connection region (joining region 31) and a coating region covered via a light guide member (covering regions 32 and 33). .. Further, in the covering region, the light that has traveled to the light receiving surface 22 side of the light transmitting member is reflected to the light extraction side, and the light loss of the primary light due to the light absorption by the substrate 50 can be suppressed. As shown in FIGS. 5 and 8, when a plurality of light emitting elements 10 are joined to one light transmitting member 20, the covering member 40 is also filled between the light emitting elements (second covering region 34). , It is preferable to cover the separated region of the light receiving surface 22. With this configuration, it is possible to enhance the heat dissipation of the separated region with respect to the heat of the light conversion member in the bonded region, and it is also preferable in the protruding portion of the light transmitting member and the first covering region 32 as described above.

(Additional member)
Further, in addition to the light-reflecting material 45 and the light conversion member, a viscosity modifier or the like can be appropriately added to the covering member 40, whereby a desired emission color, a color of the member or the surface of the device, for example, high contrast can be added. A light emitting device having a desired directional characteristic such as black color for conversion can be obtained. Similarly, various colorants can be added as a filter material that cuts unnecessary wavelengths. The same applies to other members, as well as light-transmitting materials such as a light guide member, a sealing member, and a light-transmitting member.

(Light guide member)
The light guide member 30 is used as an adhesive that is interposed between the light emitting element 10 and the light transmitting member 20 to fix both members. The light guide member is preferably made of a material that has translucency, can guide the emitted light of the light emitting element 10 to the light transmitting member side, and can optically combine both members. Examples of the material include resin materials used for the above-mentioned members, and a translucent thermosetting resin such as a silicone resin or an epoxy resin is preferable, and the silicone resin is preferable because it has excellent heat resistance and light resistance. Further, it is preferable to use a silicone resin because the effect of the fluorine-based mold release agent is high. Further, the dimethyl silicone resin is excellent in reliability such as high temperature resistance, and the phenyl silicone resin can increase the refractive index to improve the efficiency of extracting light from the light emitting element 10.

(Mounting board 50)
On the other hand, in the light emitting device 100 of FIG. 1, as the substrate 50 on which the above light emitting element 10 is mounted, a wiring 51 having at least a surface formed of a wiring 51 connected to an electrode of the element can be used, and a wiring 52 for external connection is available. Etc. may be provided. The material of the substrate is made of aluminum nitride (AlN) as an example, and is composed of single crystal, polycrystalline, sintered substrate, ceramics such as alumina as other materials, semi-metals or metal substrates such as glass and Si, and laminates thereof. Body and composite can be used, and metallic and ceramic are preferable because they have high heat dissipation. The substrate 50 may not have wiring. For example, the element shown in FIG. 4 may be mounted on the growth substrate side and the electrode of the element may be connected to the electrode of the device by wire, or the light transmitting member may be connected by providing wiring. It may be. Further, as in the illustrated light emitting device, the covering member 40 may be provided on the mounting substrate 50, or may also cover the outer side surface of the mounting substrate 50. Further, it is preferable that at least the surface of the mounting substrate 50 is made of a highly reflective material. As shown in FIGS. 1 and 2, the light emitting element 10 is adhered on the wiring 51 by the conductive adhesive 60 and electrically connected to the outside. As the conductive adhesive 60, solder, Ag paste, Au bumps and the like can be used.

(Frame, laminated substrate, base material)
The light emitting device 100 shown in FIG. 1 has a frame body 55 and is a holding member for the covering member 40. The frame body 55 can be formed of ceramic, resin, or the like. Alumina having high light reflectivity is preferable, but the present invention is not limited to this as long as a reflective film is formed on the surface. If it is a resin, screen printing or the like may be used, or the molded product may be adhered to the mounting substrate. Further, it is preferable to increase the reflectance by using a light-reflecting material as in the covering member 40. Further, similarly to the above-mentioned additive member, the frame may be colored according to the purpose. The frame can also be removed after filling or molding the covering member. Further, the frame may be formed integrally with the mounting substrate of the light emitting element, such as a laminated substrate 56, a device substrate having a cavity structure with a substrate or the like.

(Manufacturing method of light emitting device)
An example of a method for manufacturing the light emitting device 100 of the example shown in FIG. 1 will be described below. First, bumps 60 are formed on the mounting substrate 50 or on the light emitting element 10 and mounted on a flip chip. In this example, one LED chip is mounted side by side in the area corresponding to one light emitting device on the substrate 50 before the individualization. Next, the light guide member 30 is applied to the light emitting surface side of the light emitting element 10 (the back surface of the sapphire substrate or the exposed surface of the nitride semiconductor when the substrate is removed by LLO), and the light transmitting member 20 is laminated. The resin 30 is thermoset and joined. Next, the resin constituting the covering member 40 is potted by a dispenser (liquid metering discharge device) or the like so as to cover the side surface of the light transmitting member 20 in the frame 55 erected around the light emitting element 10. To do. The dropped resin 40 crawls up and covers the side surfaces of the light emitting element 10 and the light transmitting member 20 due to surface tension, and forms an inclined surface that is lower than the surface 21 toward the frame 55. Further, the exposed surface of the resin 40 may be flattened so as to be substantially the same surface as the surface 21. Then, after the resin 40 is cured, dicing is performed at a predetermined position, and the resin 40 is cut out to a desired size to obtain a light emitting device 100.

(Embodiment 2)
FIG. 5A is a schematic cross-sectional view of the light emitting device 200 according to the second embodiment of the present invention, and FIG. 5B is a schematic cross-sectional view for explaining the periphery of the light source portion thereof. In the light emitting device 200, other configurations except for the number of light emitting elements 10 and the structure of the light guide member 30 are substantially the same as those in the first embodiment described above, and therefore the same reference numerals are given to the same configurations. The description will be omitted as appropriate.

In the light emitting device of the present invention, the number of light emitting elements 10 bonded to one light transmitting member 20 is not particularly limited. By using a plurality of light emitting elements 10 with respect to the singular number of the first embodiment, a plurality of light emitting elements can be used according to the size and shape of the light transmitting member and the light emitting surface and in order to obtain desired light emitting characteristics. It can be arranged as appropriate and can be driven individually, and a light emitting surface having a desired shape and light emitting characteristics can be obtained, which is preferable. When a plurality of light emitting elements 10 are mounted, they are provided at appropriate distances from each other, and the distance is appropriately determined in consideration of the light distribution characteristics and heat dissipation of the light emitting device and the mounting accuracy of the light emitting elements. For example, it should be within 10% of the size of the light emitting element. In addition, the plurality of light emitting elements 10 may be coupled to each other. Further, in the present embodiment, the two are arranged in a row, but the present invention is not limited to this, and various arrangements such as a grid arrangement and regular and irregular arrangements are possible, and each element is preferable. It is advisable to arrange the spaces at substantially equal intervals to reduce the intensity distribution.

In the light emitting device 200, a plurality of (two in the drawing) light emitting elements 10 are mounted on the mounting substrate 50 so as to be separated from each other, and the light emitting device 200 has a light receiving surface 22 having a size including the plurality of light emitting elements 10. The transmission member 20 is joined onto the transmission member 20 via a light guide member 30. In the light emitting device 200, the frame is laminated on the substrate 50 to form a substrate 56 having a cavity structure, and is electrically connected to the wiring layer 51 for the mounting element on the upper surface side to be externally connected. A wiring layer 52 for use is also provided on the lower surface side of the substrate 56.

In such a light emitting device 200, the bonding region 31 is provided in a region facing the light receiving surface 22 of the light transmitting member and the emitting surface of each light emitting element 10. Further, the above-mentioned first covering region 32 is a light emitting element 10 arranged on the outside in the light receiving surface among the plurality of light emitting elements, and is provided on the side surface facing the outside thereof, and the peripheral edge of the light receiving surface 22. The portion is covered as a protruding surface, and a first reflecting surface 33 is provided on the outer surface thereof, and the light emitted laterally from the light emitting element 10 is reflected to the light receiving surface 22 side of the light transmitting member to guide the light. be able to. Further, in this example, although not shown, a plurality of light emitting elements are arranged at one end of the light receiving surface, and a first covering region and a first reflecting surface are provided on the side surface on the end side thereof, respectively. May be separated for each element. It is preferable that they are joined to each other and that one first covering region and the first reflecting surface are common, and they are arranged so close to each other that they are formed. At this time, it may be a first covering region in which a recess is provided between the elements.

Further, when a plurality of light emitting elements 10 are joined to the light receiving surface 22 side of one light transmitting member 20, the light guide member 30 hangs down even in a separated region sandwiched between the adjacent light emitting elements, that is, the adjacent light emitting elements. It has a second covering region 34 that extends and covers a part of the side surfaces of the element 10 facing each other and a part of the light receiving surface 22 sandwiched between the elements 10 from the bonding region 31. The second covering region 34 is usually provided so as to connect the side surfaces of the adjacent light emitting elements 10 facing each other. Further, the outer surface of the second covering region 34 is also located on the light transmitting member 20 side of the mounting surface of the light emitting element 10, that is, the light guide member is separated from the mounting substrate, so that the substrate 50 It is possible to prevent light guides from leaking and being absorbed. And this second covering area 3
A second reflecting surface 35 that reflects the light emitted from the light emitting element 10 toward the light receiving surface 22 is provided on the outer surface of the fourth. As described above, in the light emitting device in which the plurality of light emitting elements 10 are mounted on the light receiving surface 22 of one light transmitting member 20, the second reflecting surface 35 of the light guide member 30 laterally displays the light emitting elements 10 from the plurality of light emitting elements 10. The light emitted to the separated region can be satisfactorily taken out, reflected on the light receiving surface 22 side of the light transmitting member, and lightly coupled to the light transmitting member 20. Further, it is preferable that the second reflecting surface 35 also has an inclined surface similar to the first reflecting surface in the light emitting device 100 of the first embodiment. In particular, as shown in the drawing, it is preferable that one convex curved surface is formed between the elements because the light emitted from each element can be preferably reflected in the separated region and mixed with each other.

It is preferable that the second reflecting surface 35 is provided so that the distance from the light receiving surface 22 of the light transmitting member is farther than each emitting surface of the light emitting element 10. As a result, as shown in FIG. 8 (Embodiment 5), when the reflecting surface 35 or the protruding end of the convex curved surface is provided closer to the light receiving surface than the emitting surface, or when it is provided between the emitting surface and the light receiving surface. In comparison, the emitted light of each light emitting element 10 can be widely diffused and guided, reducing the decrease of the luminous flux in the separated region, and therefore, the brightness unevenness due to the arrangement of each light emitting element 10 and its light distribution. , The unevenness of chromaticity can be reduced, and the brightness in the light emitting surface can be made uniform. On the other hand, in the former case as shown in FIG. 8, each light emitting element can be easily separated and the brightness unevenness becomes large, but the light extraction efficiency can be improved, which is preferable when it is used.

Further, at least one set of the plurality of light emitting elements 10 has a different height of the emitting surface due to mounting misalignment or the like, and the distance from the emitting surface of each light emitting element to the light receiving surface 22 of the light transmitting member is different from each other. It is advisable to interpose a light guide member. As a result, it is possible to reduce the light incident from one light emitting element 10 to the adjacent light emitting element 10 and suppress the loss of the luminous flux due to the light absorption in the light emitting element 10. Such a form can be adjusted by adjusting the thickness of the conductive adhesive 60 for adhering the light emitting element 10 onto the mounting substrate 50.

Like the first reflection surface, the second reflection surface 35 is preferably provided at the interface between the light guide member 30 and the covering member 40 sandwiched between the light emitting elements 10 adjacent to the light guide member 30. In the separated region sandwiched between the adjacent light emitting elements, the surface of the substrate is often exposed without forming a metal film such as wiring on the mounting substrate 50, and light absorption is likely to occur. Therefore, at least the surface of this substrate Is preferably covered with a covering member, and more preferably, the covering member 40 is filled and the second reflecting surface 35 is provided at the interface with the covering member 40. Further, as described above, a gap may be provided between the covering member 40 filled in the separated region and the second reflecting surface 35.

(Embodiment 3)
FIG. 6 is a schematic cross-sectional view illustrating the periphery of the light source portion of the light emitting device according to the third embodiment of the present invention. In this light emitting device, the relationship between the sizes of the light emitting element 10 and the light transmitting member 20 and other configurations except for the structure of the light guide member 30 are the same as those in the above-described first embodiment, and therefore, the same configuration. Have the same reference numerals and description thereof will be omitted as appropriate. In the light emitting device of the example shown in FIG. 6, the light receiving surface 22 of the light transmitting member is smaller than the light emitting surface of the light emitting element 10, and a part of the light emitting surface projects outward from the light receiving surface 22. In other words, the side surface of the light transmitting member 20 is located inside the side surface of the light emitting element 10. In such a light emitting device, the brightness of the emitted light can be increased by using the light emitting surface 90 of the light emitting device as a window portion for emitting relatively small light. That is, unlike the above-described first and second embodiments, the light guide member extends to the protruding surface of the light emitting element and the side surface of the light transmitting member provided inside the protruding end portion to extend the region. It is covered.

In the light emitting device of the present embodiment, the light guide member 30 has a joining region 31 for joining the light emitting surface of the light emitting element 10 facing the light transmitting member and the light receiving surface 22 of the light transmitting member. Further, the light guide member 30 has a first covering region 32 that extends from the joint region 31, crawls up to the side surface of the light transmitting member 20, and covers the side surface of the light transmitting member 20. The first covering region 32 that covers the side surface of the light transmitting member 20 reflects and collects the emitted light of the light emitting element 10, and particularly reflects the light at the end thereof and guides it to the light transmitting member 20 side. Can shine. Further, since the outer surface of the first covering region 32 is also located on the light transmitting member 20 side of the mounting surface of the light emitting element 10, it is possible to prevent light from leaking to the mounting substrate 50. Here, the outer surface of the first covering region 32 facing the covering member 40 side, that is, the outer surface facing the side surface of the light transmitting member of the first covering region 32, transmits the emitted light of the light emitting element 10 to the light transmitting member. It has a first reflecting surface 33 that reflects on the 20 side. Therefore, the light transmitted through the first covering region 32 is reflected to the light transmitting member 20 side by the first reflecting surface 33, the reflected light is photocoupled to the light transmitting member 20, and the device is transmitted from the light emitting surface 90. It is released to the outside. In this way, by efficiently coupling the light emitted from the light emitting element 10 to the light receiving surface 22 side of the light transmitting member to the light transmitting member, it is possible to improve the utilization efficiency of the light emitted from the light emitting element 10. it can.

The first reflecting surface 33 in the light emitting device of the present embodiment can also have the same interface configuration as the first reflecting surface 33 in the light emitting devices 100 of the first and second embodiments, and similarly, in particular. It is preferably provided at the interface with the covering member 40. Further, the outer surface of the first covering region 32 facing the side surface of the light transmitting member 20 is an inclined surface inclined from the side surface toward the emission surface side of the light emitting element 10, and the first reflecting surface 33 is also the same. It is preferable that the surface is inclined and can be reflected well to the light transmitting member 20 side. Further, although the inclined surface may be a flat surface, the surface area of the first reflecting surface 33 can be increased by having a convex curved surface convex toward the joining region 31 as described above, and the light reflection efficiency is enhanced. It is preferable because it can be used.

On the other hand, in the light emitting device of the example shown in FIG. 6, it is preferable that the side surface of the light emitting element 10 is exposed from the light guide member 30 and is covered with the light reflecting covering member 40. In this way, the outer surface of the light guide member 30 is provided so as to connect the exit surface of the light emitting element 10 and the side surface of the light transmitting member 20, so that the light guide member 30 also covers the side surface of the light emitting element 10. Compared with the case, the bulge of the outer surface of the light guide member 30 to the outside can be suppressed. Therefore, the optical path length of the light reflected on the outer surface of the light guide member 30 to the light transmitting member 20 can be shortened, the light absorption in the light guide member 30 is reduced, and the light to the light transmitting member 20 is reduced. The binding efficiency can be increased. Further, it becomes easy to form the first reflecting surface 33 having a shape and an inclination angle suitable for light reflection toward the light transmitting member 20, and the reflection efficiency by the first reflecting surface 33 can be improved.

(Embodiment 4)
FIG. 7 is a schematic cross-sectional view illustrating the periphery of the light source portion of the light emitting device according to the fourth embodiment of the present invention. In the example shown in FIG. 7, the form of the light guide member 30 and the other configurations except for the shape of the surface 21 of the light transmitting member are substantially the same as those of the above-described first embodiment, and therefore, the same configuration is used. The same reference numerals are given and the description thereof will be omitted as appropriate. In the light emitting device of the example shown in FIG. 7, the light receiving surface 22 of the light transmitting member is larger than the emitting surface of the light emitting element 10, and a part of the light receiving surface 22 projects outward from the emitting surface of the light emitting element 10. The light guide member 30 has a joining region 31 for joining the light receiving surface 22 of the light transmitting member facing the light emitting element and the emitting surface of the light emitting element 10, and extends from the joining region 31. Covers the light receiving surface 22 of the protruding portion of the light transmitting member 20.
It has a third covering region 37 having an outer surface on the light transmitting member 20 side of the mounting surface of the light emitting element 10. Further, the side surface of the light emitting element 10 and the side surface of the light transmitting member 20 are exposed from the light guide member 30. The outer surface of the third covering region 37 has a third reflecting surface 38 that reflects the light emitted from the light emitting element 10 toward the light receiving surface 22 side of the light transmitting member 20. Here, the third covering region and the third reflecting surface are one form of the above-mentioned first covering region and the first reflecting surface, respectively.

The outer surface of the third covering region 37 is preferably an inclined surface inclined from the end of the exit surface of the light emitting element 10 toward the light receiving surface 22 side of the protruding portion of the light transmitting member 20. As a result, the third reflecting surface 38 becomes an inclined surface inclined from the end of the emitting surface of the light emitting element 10 toward the light receiving surface 22 side of the protruding portion of the light transmitting member 20, and from the emitted light of the light emitting element 10 and the light transmitting member. The reflected light and light emission of the above can be satisfactorily reflected on the light receiving surface 22 side of the light transmitting member. Further, although the inclined surface may be a flat surface, the surface area of the third reflecting surface 38 can be increased as compared with the case where the inclined surface is a flat surface by having a convex curved surface convex toward the joint region 31, and the light can be increased. It is preferable because the reflection efficiency of the light can be increased. Further, it is preferable that the third reflecting surface 38 is provided at the interface with the covering member 40 as in the case of the first reflecting surface 33 of the first embodiment, but the covering member 40 is separated from the covering member 40 by a gap. Alternatively, it may be formed by providing a metal film or a dielectric multilayer film.

By joining the light emitting element 10 and the light transmitting member 20 with such a light guide member 30, the light emitting element is compared with the case where the light emitting element 10 and the light transmitting member 20 are joined only in the joining region 31. The emitted light of 10 can be suitably combined, and the brightness and chromaticity distribution in the light emitting surface can be made uniform. Since the light guide function of the light guide member 30 depends on the protruding length of the side surface of the light emitting element 10 with respect to the side surface of the light transmitting member 20, for example, it may be in the above range. Such a coating form of the light guide member 30 can be achieved by appropriately adjusting the amount, protrusion width, and surface area of the light guide member, and the light emitting element 10 is coated with a mold release agent over substantially the entire side surface of the light emitting element 10. This can be achieved by preventing the light guide member 30 from hanging down to the side surface of the light guide member 30. A mold release agent may be applied to the side surface of the light transmitting member 20, and the light transmitting member 20 can be manufactured with high accuracy. In this example, since the side surface of the light emitting element is exposed, the side surface is not covered as in the first and second embodiments, so that the return light and the converted light are suppressed from re-entering the element by the light guide member. That is, the contact area between the light guide member and the light emitting element can be minimized, and the coupling efficiency can be improved. Further, in the example shown in FIG. 7, the surface 23 of the light transmitting member is an uneven surface, and the light transmitted through the light transmitting member 20 is scattered by the unevenness to improve the efficiency of extracting light from the light transmitting member 20. In addition, uneven brightness and uneven color can be reduced, and uniform light distribution can be achieved. In particular, when a plurality of light emitting elements 10 are mounted, the brightness unevenness and the color unevenness caused by the mounting are reduced, which is preferable. Such irregularities can be processed by polishing, dry etching, wet etching, or the like on the surface of the light transmitting member, and can form irregular irregularities as well as irregular patterns. Further, such a concave-convex structure can be provided not only on the surface of the light transmitting member but also on the light receiving surface and the surface of each member on the optical path to obtain the same effect. It may be provided on the surface of a member in contact with the member, for example, on the surface of the substrate 1 on the semiconductor layer 11 side, and such a structure is used although not described in detail in the examples.

(Modification example)
In the above-described first to fourth embodiments, the case where one of the light emitting element and the light transmitting member is included in the other, that is, inside the other is described, but the light emitting device in the light emitting device of the present invention emits light. The relationship between the element and the light transmitting member is not limited to this form, and one of them may have at least a partially protruding portion protruding outward from the other. For example, one of the side surfaces constituting the light emitting element, or a part of one side surface protrudes outward from the side surface constituting the light transmitting member, and the other side surfaces are substantially the same surface as each other, or light transmission. The form may be such that the member protrudes, and vice versa. In such a form, a first covering region is provided on one of the protruding side surfaces or a part of the side surface thereof. Further, in the top view, protrusions may be provided on both sides of either the light emitting element or the light transmitting member. In the case of such a form, at least one of the first covering area 32 described in the first embodiment and the second embodiment is provided in the cross section of the region having the protruding portion. Further, when there are a plurality of light emitting elements, the light emitting element and the light transmitting member may be provided with a first covering region in each element and coexist. Preferably, it is preferable in terms of the function of the light guide member to have a form in which the first covering region is provided on one of them, that is, one of the first and third embodiments, and substantially the same surface on a part of the side surface thereof. May be mixed. More preferably, it is preferable that the first covering region is unified with the light emitting element over the entire outer circumference of the light transmitting member in any form. This is because unevenness in the brightness and chromaticity in the light emitting surface can be reduced, and it is most preferable that one side surface of the light emitting element and the light transmitting member is included inside the other.

As described above, the light guide member in the present invention is provided between the surfaces of the light emitting element and the light transmitting member and between them, and the two are photocoupled to form a composite light source, and the element and the member are formed. In between, the junction region to which they face and one protruding surface, or the other end face provided inside it and its end, extend from the junction region and are covered with the first covering region. Is provided. Specifically, since the light guide member uses a resin material and is also used as an adhesive, as described above, by providing a protruding surface, the light guide member wets and spreads from the joint region to the surface, and also from the protruding surface. Further, it may be wet and spread to the side surface which is the other end. As described above, since the light guide member utilizes the wetting of the resin on each surface at the time of its production, specifically before the resin is cured, first, the amount of the material, the coating method thereof, and the protruding surface are described. It can be controlled by the protrusion width and area of the resin, and in addition, the spread to other regions can be controlled by using a mold release agent. Therefore, as a specific form of the light guide member, it is preferable that the wall thickness of the light guide member is smaller than that of the light transmitting member and further smaller than that of the growth substrate in the joint region to reduce the composite light source and increase its coupling efficiency. Further, the protruding width at that time is set to about 0.25 to 5 times the wall thickness of the light emitting element or the light transmitting member so that it can be easily controlled at the time of manufacturing, and the diffusion of light from a suitable element can be achieved. Can collect light. As described above, when covering the other end from one protruding portion, it is preferable that the end on the protruding portion side is exposed, and when it is covered, as shown in the first and third embodiments. In comparison, it is preferable that the spread of the light source can be suppressed and each characteristic of the present invention can be improved. Further, in the case of coating, if the wall thickness is thinner than that of the other end portion, the influence thereof can be reduced, and the same effect as that of the coating member described later can be expected, which is preferable.

Further, as described above, it is preferable that the covering region of the protruding surface is thinner than the bonding region as shown in FIG. 7, but the effect of the present invention can be obtained even if the side surface of the element is exposed by mold release treatment to be thickened. You can expect it. As seen in the first and third embodiments, various characteristics are affected by the covering region on the side surface of the device, but when the translucent substrate 1 made of a different material from the semiconductor layer 11 is provided, the substrate is used. By covering the light guide member, the function of the light guide member can be assisted as a light propagation region between the light transmitting member and the element, which is preferable. In particular, in the case of an optical conversion member, since the component of the converted light is also included in the region, it is effective in chromaticity unevenness and orientation. Further, in the element from which the substrate 1 has been removed, the light component from the exit surface is much larger than that on the side surface, so that the side surface of the element may be exposed. As described above, the presence of the covering member can assist the function of the light guide member in confining light to the composite light source, emitting light from the light emitting surface, and coupling the light, but reflects like a metal film or a dielectric multilayer film. A membrane can also be used as a substitute. When the light-reflecting material is provided as in the embodiment, the light seeps into the base material, so that the light of the light source spreads more than the inside of the coating, thereby improving the efficiency of light diffusion and condensing. Further, it is preferable because it contributes synergistically to the function of the light guide member, and is preferable for light emission characteristics, brightness unevenness, and directivity. Further, also in the case of an optical conversion member, it is preferable to contribute to color unevenness and orientation, and further, by covering the side surface thereof, the color and wavelength component ratio are different from those of the surface 21, and the side surface is relatively high. It is preferable because the light emission can be suppressed.

Further, the member having the protruding portion of the light emitting element 10 and the light transmitting members 20 and 24 does not have to have a clear boundary between the surface on the side facing the other member and the side surface continuous from the surface. .. For example, in the light emitting device 100 of the first embodiment, the light receiving surface 22 and the side surface of the light transmitting member 20 may be integrated into one curved surface, for example, a spherical surface or a part thereof. Further, when the light receiving surface 22 of the light transmitting member and the emitting surface of the light emitting element 10 are directly bonded by crystal bonding or the like by thermocompression bonding, the protruding portion has a first coating region, and a plurality of light emitting elements are provided. Can also form a light guide member 30 having a second covering region between the elements.

(Embodiment 5)
FIG. 8 is a schematic cross-sectional view of the light emitting device 300 according to the fifth embodiment of the present invention, and the same reference numerals are given to the light emitting device 300 having substantially the same configurations as those of the above-described first to fourth embodiments. The description will be omitted as appropriate. In the example shown in FIG. 8, a surface emitting type light source in which the light emitting element 10 and the light transmitting member 20 are covered with a coating member 40 containing a light reflecting material 45 and the surface 21 of the light transmitting member 20 is used as a light emitting surface is used. A sealing member 80 which is formed, covers the light source, and further covers a part of the covering member to be a hemispherical optical lens is provided. In this light emitting device 300, a plurality of (two in the figure) light emitting elements 10 are flip-chip mounted on a wiring pattern 51 on the upper surface side of the mounting substrate 50, and one light transmitting member 20 guides the light emitting element 20 on the flip chip. It is joined by a member 30. In the frame body seen in the first embodiment, the covering member 40 is removed after molding in this example, and the side surface of the covering member 40 is exposed to the outside to form the outer surface of the light emitting device. The width of the cross section of the light receiving surface 22 of the light transmitting member is smaller than the distance between the outer side surfaces of the light emitting element 10 located on the outermost side, in other words, smaller than the width of the region where the plurality of light emitting elements are provided. Further, the side surface of the light emitting element 10 located at the outermost surface projects outward from the side surface of the light transmitting member 20. The light guide member 30 has a second covering region and a second reflecting surface 35 similar to those in the second embodiment in a separated region sandwiched between adjacent light emitting elements, and has a side surface of the light transmitting member 20. A first covering region and a first reflecting surface 33 similar to those in the third embodiment are provided in a region connecting the light emitting element 10 and the protruding portion of the emitting surface of the light emitting element 10 located at the outermost surface.

According to such a configuration of the light emitting device 300, the light emitted from the light emitting element 10 is transmitted by the first and second covering regions of the light guide member 30, the first and second reflecting surfaces 33 and 35. Light can be efficiently coupled to the member 20 and light can be efficiently taken out from the light transmitting member 20 to the sealing member 80, so that a light emitting device having a higher output can be obtained. Further, the optical lens 80 exaggerates or changes the emitted light due to the light distribution characteristics on the surface 21 of the light transmitting member, but the light guide member 30 of the present invention can make the brightness and chromaticity unevenness of the light uniform. Therefore, a light emitting device having excellent light distribution characteristics can be obtained. Further, the sealing member 80 continuously covers the surface 21 of the light transmitting member and a part of the surface of the covering member 40, and reflects the light of the sealing member 80 on the surface of the covering member 40 to the outside. By efficiently taking out the light and making the surface of the covering member 40 on the light emitting side a concave surface inclined from the side surface of the light transmitting member 20 toward the substrate 50, the light is diffused and the emitted light of the light emitting device can be oriented widely. As described above, in the light emitting device of the present invention, an optical member can be bonded to the surface of the light transmitting member on the light emitting surface to obtain desired light emitting characteristics.

(Sealing member)
Here, if the sealing member 80 has a lower refractive index than the light transmitting member, it can be joined to the surface 21 of the sealing member 80 to improve the light extraction efficiency. The surface of the sealing member 80 on the light emitting side can be formed into various shapes depending on the purpose. For example, as shown in FIG. 8, by forming the surface on the light emitting side into a spherical (hemispherical) lens shape and a convex curved surface, it is possible to efficiently take out the light emitted from the light transmitting member to the outside. Further, the present invention is not limited to this, and various optical elements and optical members having a desired shape can be formed, a concave lens shape, a radial curved surface, and a convex shape having a flat tip can be formed, and light may be scattered as a concave-convex surface.

The sealing member 80 is a resin such as an epoxy resin, a silicone resin, a modified silicone resin, a urea resin, a urethane resin, an acrylic resin, a polycarbonate resin, or a polyimide resin, similarly to the base material and the light guide member of the coating member 30 described above. It can be formed using a material. Further, since the sealing member 80 also serves as a sealing material for protecting the light emitting element 10 and the light transmitting member 20, a material having excellent weather resistance, heat resistance, and hardness is preferable, and among the above, epoxy resin or epoxy resin or A hard silicone resin is preferred. In addition, glass may be used. Further, the above-mentioned phosphor and / or _{light scattering particles such as TiO 2} and / or a filler such as quartz glass can be appropriately added to the sealing member 80. The sealing member 80 is formed by compression molding, transfer molding, or the like.

(Embodiment 6)
FIG. 9 is a schematic cross-sectional view of the light emitting device 400 according to the sixth embodiment of the present invention, and the same reference numerals are given to substantially the same configurations as those of the first and second embodiments described above, and the description thereof will be omitted as appropriate. To do. In the light emitting device 400 of the example shown in FIG. 9, the light emitting element 10 is flip-chip mounted at substantially the center of the bottom of the mounting base (package) 56 having a recess. The mounting portion is a part of the mounting base 56, but may be a submount. A light transmitting member 24 is placed and joined on the light emitting element 10 via a light guide member 30. Then, the recess is closed by the light conversion member 81 having a surface in which the recess is filled with the sealing member 84 and becomes the light emitting surface 82 of the light emitting device 400. The light transmitting member 24 and the light converting member 81 can have the same configuration as when the above-mentioned light transmitting member and the above-mentioned light transmitting member 20 contain a wavelength conversion material, respectively, and the sealing member is also the fifth embodiment. It can be composed of the same structure as that of the above, for example, a translucent resin. In particular, in this example, the light transmitting member 24 does not have to contain a wavelength conversion material, and in addition to the plate shape as shown in the figure, an optical element capable of condensing and diffusing may be used, and a light scattering material may be mixed. Further, a reflective film having a concave curved surface is provided so as to cover the convex side surface of the mounting portion from the inner surface of the concave portion, and reflection and light can be collected toward the respective members 24 and 84. Here, the reflective film is formed of the covering member 41 containing the light-reflecting material 46, and is formed as a concave reflective surface by the above-mentioned creeping up of the resin. The coating member 41 may have a highly reflective metal film such as Ag or Al formed on the surface thereof as a substitute for the coating member 41, or may be provided with a light conversion member containing a phosphor as described above. Alternatively, the inner surface of the mounting substrate may be a reflective surface as in the conventional case without providing a covering member. Further, in the recess, the sealing member 84 may contain a light conversion member, may be airtightly sealed, or may be in the atmosphere, and the member 81 may be a member that does not contain a light conversion member like the member 24. .. That is, an optical conversion member may be provided on any of the members 24, 41, 81, and 84 to form a light emitting device that includes the converted light, and a light emitting device that extracts the light emitted from the light emitting element without being included in any of the members may be used.

In such a light emitting device 400, similarly to the second embodiment, the light guide member 30 has the above-mentioned joining region 31, the first covering region, and the first reflecting surface 33, and the inside of the recess is sealed. Since it is filled with the member 84, the outer surface of the first covering region forms an interface with the translucent sealing member, and the first reflecting surface 33 is provided at the interface. That is, if a difference in refractive index is provided between the light guide member and the sealing member, the interfacial reflection can be utilized, and if the first covering region side has a high refractive index, the reflectance can be increased, which is preferable, and even in the case of airtight sealing. The same is true. Light is diffused and emitted from the light emitting element 10 in all directions, and a part of the light component is reflected by the inner surface of the first reflecting surface 33 toward the light receiving surface 26 side of the light transmitting member 24. It is emitted from the light emitting surface 25, and a part of it is reflected by the concave portion.
It can be taken out from the light transmitting member 81. Therefore, the light of the light emitting element 10 is collected by the light transmitting member 24 and emitted from the surface 25 to increase the brightness of the light emitting surface 82 in the front direction, suppress the diffusion of light in the recess, and reduce the light absorption. be able to. The same applies to the second reflecting surface 35 and its second covering region.

Further, in the case of the fourth embodiment in which the light emitting element 10 is not coated on the light reflecting covering member 40, the covering range of the first and second covering regions provided on the side surface of the light emitting element 10 is implemented. It is preferable that it is the same as that of the first embodiment or wider than the first embodiment. If the coverage range of the light guide member 30 on the side surface of the light emitting element 10 is wide, the efficiency of extracting light from the light emitting element 10 into the light guide member 30 can be improved, and the surface areas of the first and second reflecting surfaces 33 and 35 can be further increased. It can be increased, and the efficiency of binding light to the light transmitting member 20 can be increased. However, as described above, in order to avoid light loss due to light absorption by the mounting substrate 56, the light guide member 30 has an outer surface located on the light transmitting member 20 side of the mounting surface of the light emitting element 10. It is preferable that the mounting base 56 is separated from the surface of the mounting base 56.

Hereinafter, examples according to the present invention will be described in detail. Needless to say, the present invention is not limited to the examples shown below.

(Example 1)
As shown in FIG. 5, the light source portion of the light emitting device of the first embodiment is a substantially square LED chip (nitride on the sapphire substrate 10) of about 1 mm × 1 mm as the light emitting element 10 on the wiring 51 of the AlN ceramic substrate 50. Two light emitting wavelengths (455 nm) are mounted on a flip chip in a structure in which physical semiconductors 11 are laminated, and YAG and alumina (Al ₂ O ₃ ) are sintered as a light transmitting member 20 which is a plate-shaped light conversion member. The outer shape of the body, the surface 21 and the light receiving surface 22 is approximately 1.1 mm × 2.2 mm in a substantially rectangular shape, and one sheet having a thickness of about 150 μm is placed and joined to each other by a light guide member 30. At this time, an appropriate amount of the silicone resin to be the light guide member 30 is applied with tweezers on the emission surface (back surface of the substrate 1) of each LED, and the light transmitting member 20 is placed on the light transmitting member 20 with tweezers. The resin is thermoset for 60 minutes in an oven at 150 ° C., and the two LEDs are adhered so as to be included in the light receiving surface of the light transmitting member as shown in the figure. In this way, the light guide member 30 covers the joint region 31 between the LED and the light transmitting member, the first covering region 32 that covers the outer side surface of the light source of the LED, and the inner side surface between the LEDs. A second covering region 34 is formed, and at this time, a light guide member is formed on a substrate and a part or substantially all of the semiconductor layer 11 on the side surface of the LED. Then, as shown in FIG. 1, the LED is mounted on the wiring 51 of the substrate 50, the coating member 40 is filled in the recess inside the frame surrounding the light emitting element 10 and the light transmitting member 20, and the light transmitting member is filled. Light emitting element 10 in a state where the surface 21 of 20 is exposed as a light emitting surface.
The light transmitting member 20 is covered with the covering member 40, and the frame is removed as shown in FIG. 8 to obtain a light emitting device. Here, the coating member 40 is a silicone resin containing a light-reflecting material 45, which is a fine particle _{of TiO 2 having a particle size of about 270 nm, at a concentration of about 23 weight percent.} When the light emitting device of the first embodiment is driven by a current of 350 mA, it has a luminous flux of about 167 [lm] (chromaticity y value of about 0.339), a maximum brightness of 6086 [cd / cm ² ], and an average brightness of 3524 [cd / cm]. ^A high luminous flux and high brightness that emits light in 2] can be obtained.

(Example 2)
As shown in FIG. 6, the light emitting device of the second embodiment has a form in which a light receiving surface of one light transmitting member is included in the emitting surface of one light emitting element, and the light emitting element of the first embodiment is a sapphire. One LED chip 10 having a substantially rectangular shape of about 1 mm × 6.5 mm having six element structures provided on the substrate, and the light transmitting member 20 having a substantially rectangular shape of about 0.8 mm × 6.3 mm. A light emitting device is produced in the same manner as in Example 1. When the light transmitting member 20 is placed, the light transmitting member 30 is lightly pressed to crawl up on a part of the side surface of the light transmitting member 20 to form the first covering region 32. When the light emitting device of the second embodiment is driven by a current of 700 mA, it has a luminous flux of about 740 [lm] (chromaticity y value of about 0.280), a maximum brightness of 4629 [cd / cm ² ], and an average brightness of 4123 [cd / cm]. ^A high luminous flux and high brightness that emits light in 2] can be obtained.

The light emitting device of the present invention can be suitably used for a lighting light source, an LED display, a backlight light source such as a liquid crystal display device, a traffic light, an illuminated switch, various sensors, various indicators, and the like.

10 ... Light emitting element (1 ... Growth substrate, 2 ... First conductive type (n type) semiconductor layer, 3 ... Active layer, 4 ... Second conductive type (p type) semiconductor layer, 5 ... Translucent conductive layer, 6 ... 2nd electrode (p-side pad electrode), 7 ... 1st electrode (n-side pad electrode), 8 ... protective film, 11 ... element structure)
20, 24 ... Light transmitting member (21, 23, 25 ... Surface, 22, 26 ... Light receiving surface)
30 ... Light guide member (31 ... Joining region, 32 ... First covering region, 33 ... First reflecting surface, 34 ... Second covering region, 35 ... Second reflecting surface, 37 ... Third covering region , 38 ... 3rd reflective surface), 40, 41 ... Covering member, 45, 46 ... Light reflective material 50 ... Mounting substrate (51, 52 ... Wiring, 55 ... Frame, 56 ... Laminated substrate or base material), 60 ... Conductive adhesive

Claims (7)

A substrate with a recess having a mounting portion on the bottom,
The light emitting element mounted on the mounting portion and
A light transmitting member bonded onto the light emitting element via a light guide member,
A covering member that covers the mounting portion from the inner surface of the recess, and
An optical element that closes the recess,
A light emitting device equipped with. The light emitting device according to claim 1, wherein the light guide member is arranged apart from the surface of the substrate. The light emitting device according to claim 1 or 2, wherein the recess is filled with a translucent resin. The light emitting device according to claim 1 or 2, wherein the recess is hermetically sealed. The light emitting device according to any one of claims 1 to 4, wherein the light transmitting member contains a wavelength conversion material. The light emitting device according to any one of claims 1 to 5, wherein the mounting portion is a convex portion. The light emitting device according to any one of claims 1 to 5, wherein the mounting portion is a sub-mount.

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