JP7071652B2 - Light emitting device and its manufacturing method - Google Patents

Description

The present disclosure relates to a light emitting device and a method for manufacturing the same.

For example, in Patent Document 1, a blue LED element having a − electrode and a + electrode formed on the lower surface, a phosphor layer formed on the upper surface of the LED element so as to emit total white light, and a surface surface of the LED element are formed. Described is a light emitting device including an inverted square cone-shaped transparent resin portion having a phosphor layer as a bottom surface, and a reflective wall covering an exposed surface other than the lower surface of the LED element and the upper surface of the phosphor layer. There is.

Japanese Unexamined Patent Publication No. 2015-115480

In the light emitting device described in Patent Document 1, the region of the phosphor layer located directly above the transparent resin portion has lower heat dissipation and is more likely to deteriorate than the region of the phosphor layer located directly above the LED element. .. However, if the phosphor in this region is simply eliminated, the light of the LED element may be emitted diagonally above the light emitting device without being mixed with the light of the phosphor, resulting in a large unevenness in the emission chromaticity distribution.

Therefore, one embodiment of the present invention aims to provide a light emitting device that easily draws heat from a fluorescent substance and has less unevenness in the emission chromaticity distribution. Another embodiment of the present invention is an object of the present invention to provide a method for manufacturing such a light emitting device with good productivity.

The light emitting device according to the embodiment of the present invention has a light emitting element, a first region arranged above the light emitting element and located directly above the upper surface of the light emitting element, and a first region located laterally from the first region. A light-transmitting member composed of a second region, a light guide member that covers the side surface of the light emitting element and the lower surface of the second region of the light-transmitting member, and light reflection that covers the outer surface of the light guide member. The translucent member includes a fluorescent substance and a light scattering material that is not a fluorescent substance, and the concentration of the fluorescent substance is higher in the first region than in the second region. It is high, and the concentration of the light scattering material is higher in the second region than in the first region.

The method for manufacturing a light emitting device according to an embodiment of the present invention includes a first region located directly above the upper surface of the light emitting element and a second region located laterally from the first region above the light emitting element. A step of covering the side surface of the light emitting element and the lower surface of the second region of the translucent member with a light guide member to provide the translucent member including The translucent member comprises a fluorescent substance and a light scattering material that is not a fluorescent substance, and the concentration of the fluorescent substance is the first from the second region. It is characterized in that it is high in the region and the concentration of the light scattering material is higher in the second region than in the first region.

According to one embodiment of the present invention, it is possible to obtain a light emitting device that easily draws heat from a fluorescent substance and has less unevenness in the emission chromaticity distribution. Further, according to another embodiment of the present invention, such a light emitting device can be manufactured with high productivity.

It is a schematic top view of the light emitting device which concerns on one Embodiment of this invention. FIG. 3 is a schematic cross-sectional view taken along the line AA of the light emitting device shown in FIG. 1A. FIG. 3 is a schematic cross-sectional view taken along the line BB of the light emitting device shown in FIG. 1A. It is a schematic sectional drawing which shows one step in the manufacturing method of the light emitting device which concerns on one Embodiment of this invention. It is a schematic sectional drawing which shows one step in the manufacturing method of the light emitting device which concerns on one Embodiment of this invention. It is a schematic sectional drawing which shows one step in the manufacturing method of the light emitting device which concerns on one Embodiment of this invention. It is a schematic sectional drawing which shows one step in the manufacturing method of the light emitting device which concerns on one Embodiment of this invention. It is a schematic top view of the light emitting device which concerns on another embodiment of this invention. FIG. 3 is a schematic cross-sectional view taken along the line CC of the light emitting device shown in FIG. 3A. FIG. 3 is a schematic cross-sectional view taken along the line DD of the light emitting device shown in FIG. 3A. It is schematic cross-sectional view which shows one step in the manufacturing method of the light emitting device which concerns on another Embodiment of this invention. It is schematic cross-sectional view which shows one step in the manufacturing method of the light emitting device which concerns on another Embodiment of this invention. It is schematic cross-sectional view which shows one step in the manufacturing method of the light emitting device which concerns on another Embodiment of this invention. It is schematic cross-sectional view which shows one step in the manufacturing method of the light emitting device which concerns on another Embodiment of this invention.

Hereinafter, embodiments of the invention will be described with reference to the drawings as appropriate. However, the light emitting device and the manufacturing method thereof described below are for embodying the technical idea of the present invention, and the present invention is not limited to the following unless otherwise specified. Further, the contents described in one embodiment can be applied to other embodiments. In addition, the size and positional relationship of the members shown in the drawings may be exaggerated for the sake of clarity.

In each figure, the width direction of the light emitting device is shown as the X direction, the depth direction is shown as the Y direction, and the vertical (thickness) direction is shown as the Z direction. The X, Y, and Z directions (axises) are directions (axises) perpendicular to the other two directions (axises), respectively. More specifically, the right direction is the X + direction, the left direction is the X− direction, the back direction is the Y + direction, the front direction is the Y− direction, the upward direction is the Z + direction, and the downward direction is the Z− direction. The main light emitting direction of the light emitting device is upward. The lateral direction is, for example, a direction parallel to a plane including the width direction and the depth direction, that is, the XY plane.

The visible wavelength range is a wavelength range of 380 nm or more and 780 nm or less, the blue range is a range of 420 nm or more and 480 nm or less, the green range is a range of 500 nm or more and 560 nm or less, and the yellow range is a wavelength longer than 560 nm and 590 nm or less. The wavelength range of 610 nm or more and 750 nm or less is defined as the range of red.

Further, "translucency" in the present specification means that the light transmittance at the emission peak wavelength of the light emitting element is 60% or more, preferably 70% or more, and preferably 80% or more. Is more preferable. The term "light reflectance" as used herein means that the light reflectance at the emission peak wavelength of the light emitting device is 60% or more, preferably 70% or more, and more preferably 80% or more. preferable.

<Embodiment 1>
FIG. 1A is a schematic top view of the light emitting device 100 according to the first embodiment. FIG. 1B is a schematic cross-sectional view taken along the line AA of the light emitting device 100 shown in FIG. 1A. FIG. 1C is a schematic cross-sectional view taken along the line BB of the light emitting device 100 shown in FIG. 1A.

As shown in FIGS. 1A to 1C, the light emitting device 100 of the first embodiment includes a light emitting element 10, a translucent member 20, a light guide member 30, and a light reflecting member 40. The translucent member 20 is arranged above the light emitting element 10. The translucent member 20 includes a first region 20a located directly above the upper surface of the light emitting element 10, and a second region 20b located laterally from the first region 20a. The light guide member 30 covers the side surface of the light emitting element 10 and the lower surface of the second region 20b of the translucent member. The light reflective member 40 covers the outer surface of the light guide member 30. The translucent member 20 contains a fluorescent substance 25 and a light scattering material 28 that is not a fluorescent substance. The concentration of the fluorescent substance 25 is higher in the first region 20a than in the second region 20b. Further, the concentration of the light scattering material 28 is higher in the second region 20b than in the first region 20a.

The light emitting device 100 having such a configuration conducts heat generated by the fluorescent substance 25 because the concentration of the fluorescent substance 25 in the translucent member 20 is higher in the first region 20a than in the second region 20b. It is easy to pull through the light emitting element 10 having a relatively high property, and heat generation and heat stagnation in the second region 20b can be suppressed. As a result, deterioration of the second region 20b due to heat can be suppressed. Further, deterioration of the light guide member 30 adjacent to the second region 20b can be suppressed. Therefore, the reliability of the light emitting device 100 can be improved. Further, in the light emitting device 100, the concentration of the light scattering material 28 in the translucent member 20 is higher in the second region 20b than in the first region 20a, so that the light of the light emitting element 10 is in the second region 20b. It becomes easy to be scattered, the directivity of the light of the light emitting element 10 in the diagonally upward direction of the light emitting device 100 is weakened, and the unevenness of the emission chromaticity distribution can be suppressed. Further, since the light scattering by the light scattering material 28 increases the chance of the light of the light emitting element 10 being incident on the fluorescent substance 25, the wavelength conversion rate becomes relatively high in the second region 20b where the concentration of the light scattering material 28 is high. This also contributes to the suppression of unevenness in the emission chromaticity distribution. Further, the light scattering material 28 may enhance the thermal conductivity of the second region 20b. Since the light scattering material 28 is not a fluorescent substance, it generates little heat, and even if it has a high concentration, it is unlikely to cause deterioration of the second region 20b due to heat. From the above, the light emitting device 100 can be a light emitting device that easily draws heat from the fluorescent substance 25 and has less unevenness in the emission chromaticity distribution.

The concentration of the fluorescent substance 25 and the light scattering material 28 is preferably a volume concentration from the viewpoint of its action. The same applies to the concentration of the second fluorescent substance 26 described later.

Further, as shown in FIG. 1A, in the first embodiment, the top view shape of the translucent member 20 is rectangular, and the top view shape of the light guide member 30 is circular. Therefore, the second region 20b has a region located directly above the light guide member 30 and a region lateral to the region and located directly above the light reflecting member 40. In the region located directly above the light guide member 30, the light of the light emitting element 10 having a high radiant flux is incident from the light guide member 30 and the fluorescent substance 25 is likely to emit light. Further, in general, the light reflective member 40 contains a large amount of a pigment or the like for imparting light reflectivity, and has higher thermal conductivity than the light guide member 30 which requires high translucency. For this reason, among the second regions 20b, the region located directly above the light guide member 30 is a region that tends to become hot and easily deteriorates. Therefore, the region in the second region 20b where the temperature tends to be high depends on the coverage range of the light guide member 30 on the lower surface of the second region 20b.

Further, from the viewpoint of heat dissipation and uniformity of emission chromaticity distribution, it is preferable that the center of the light emitting element 10 and the center of the translucent member 20 in the top view are substantially the same. When the center of the light emitting element 10 and the center of the translucent member 20 are separated from each other in the top view, the separation distance is ½ or less of the minimum width of the second region 20b when both centers are aligned. It is preferably present, and more preferably 1/4 or less. When a plurality of light emitting elements are connected to one translucent member, the center of the light emitting element is a virtual shape formed by connecting the outer contours of the plurality of light emitting elements located on the outermost side in the top view. Let's think at the center of.

Hereinafter, preferred embodiments of the light emitting device 100 will be described in detail.

Since the light scattering material 28 can exhibit Rayleigh scattering in which the scattering intensity of short wavelength light is dramatically increased, the light scattering of the light emitting element 10 in the second region 20b can be effectively obtained, and the light emitting device 100 can effectively obtain the light scattering. It is easy to reduce the unevenness of the emission chromaticity distribution. Therefore, the average particle size of the light scattering material 28 is preferably smaller than the emission peak wavelength of the light emitting element 10, more preferably 1/5 or less of the emission peak wavelength of the light emitting element 10, and the emission peak of the light emitting element 10. It is even more preferable that the wavelength is 1/10 or less. In concrete terms, the average particle size of the light scattering material 28 is preferably smaller than 500 nm, more preferably smaller than 100 nm, and even more preferably smaller than 50 nm. The lower limit of the average particle size of the light scattering material 28 is, for example, 1 nm. The average particle size is preferably the primary particle size, but in reality, the aggregation of particles cannot be ignored and the average particle size includes the secondary particle size. The average particle size can be defined by D50. The average particle size shall be measured by an image analysis method (scanning electron microscope (SEM), transmission electron microscope (TEM)), laser diffraction / scattering method, dynamic light scattering method, small-angle X-ray scattering method, or the like. Can be done. Among them, the image analysis method is preferable in consideration of measuring the particle size of the particles existing in the member. The image analysis method conforms to, for example, JIS Z 8827-1: 2008.

As shown in FIGS. 1B and 1C, in the light emitting device 100 of the first embodiment, the concentration of the fluorescent substance 25 is the lowest at the side end portion of the second region 20b and the highest at the central portion of the first region 20a. There is. As the translucent member 20 approaches its side end, that is, its side surface, the optical path length from the light emitting element 10 becomes longer, and the wavelength conversion rate of the light of the light emitting element 10 by the fluorescent substance 25 tends to increase, and the light emitting element 10 tends to have a higher wavelength conversion rate. Since the distance from is large, the heat dissipation tends to be low. Therefore, since the fluorescent substance 25 is distributed at a low concentration at the side end portion of the second region 20b and at a high concentration at the central portion of the first region 20a, it is easy to suppress the unevenness of the emission chromaticity distribution, and the fluorescent substance 25 can be easily suppressed. It becomes easier to draw heat from. In particular, in the example shown in FIGS. 1B and 1C, the fluorescent substance 25 is contained from the central portion of the first region 20a to the side end portion of the second region 20b. More specifically, the fluorescent substance 25 is continuously contained from the central portion of the first region 20a to the side end portion of the second region 20b. The concentration of the fluorescent substance 25 gradually increases as it approaches the center of the first region 20a from the side edge of the second region 20b. The "center portion" of the first region 20a includes a range within 5% of the maximum width of the translucent member 20 (diagonal width if the top view is rectangular) from the center of the first region 20a. .. Further, the "side end portion" of the second region 20b is a range within 5% of the maximum width of the translucent member 20 (diagonal width in the case of a rectangular shape in the top view) from the side end of the second region 20b. It shall include.

As shown in FIGS. 1B and 1C, in the light emitting device 100 of the first embodiment, the concentration of the light scattering material 28 is the lowest in the central portion of the first region 20a and the highest in the side end portion of the second region 20b. ing. In this way, the light scattering material 28 is distributed in the translucent member 20 in a concentration relationship opposite to that of the fluorescent substance 25, so that the light scattering and / or the wavelength conversion rate of the light emitting element 10 in the translucent member 20 is achieved. It is possible to improve the uniformity of the light emission and it is easy to suppress the unevenness of the emission chromaticity distribution. In particular, in the example shown in FIGS. 1B and 1C, the light scattering material 28 is contained in the central portion of the first region 20a and the side end portion of the second region 20b. More specifically, the light scattering material 28 is continuously contained from the central portion of the first region 20a to the side end portion of the second region 20b. The concentration of the light scattering material 28 gradually increases as it approaches the side edge of the second region 20b from the center of the first region 20a.

As shown in FIGS. 1B and 1C, in the light emitting device 100 of the first embodiment, the light guide member 30 does not contain a fluorescent substance. As a result, heat generation in the light guide member 30 is suppressed. Therefore, the heat generated by the fluorescent substance 25, particularly the heat of the second region 20b, can be easily drawn through the light guide member 30. Further, deterioration of the light guide member 30 can be expected to be suppressed.

As shown in FIGS. 1B and 1C, the light emitting element 10 includes a translucent substrate 11 and a semiconductor laminate 15. The upper surface of the light emitting element 10 is the surface of the substrate 11. The semiconductor laminate 15 is a light source and a heat source of the light emitting element 10, and is relatively thin, about several μm. Therefore, when the substrate 11 is interposed between the semiconductor laminate 15 and the translucent member 20, the light of the semiconductor laminate 15 propagates in the substrate 11 and appropriately spreads laterally to form the second region 20b. The light distribution is suitable for the translucent member 20 to have, and it becomes easy to suppress the unevenness of the emission chromaticity distribution. Further, by moving the translucent member 20 away from the semiconductor laminate 15, the influence of the strong light and heat emitted by the semiconductor laminate 15 is alleviated, and the deterioration of the translucent member 20 can be suppressed.

As shown in FIGS. 1B and 1C, an electrode 50 is provided on the lower surface of the light emitting element 10. The electrode 50 constitutes a part of the lower surface of the light emitting device 100. Such a light emitting device 100 is called, for example, a chip size package (CSP) type, and can be formed to be smaller than a PLCC (Plastic Leaded Chip Carrier) type. The electrode 50 is made of a metal material, is a terminal for supplying power to the light emitting element 10, and is also an important element from the viewpoint of the heat dissipation path of the light emitting device 100. If the light emitting device 100 is small, the distance from the heat generating portion to the electrode 50 tends to be small, and the heat dissipation through the electrode 50 can be improved.

(Manufacturing method of light emitting device 100)
In the method of manufacturing the light emitting device 100 of the first embodiment, a first region 20a located above the light emitting element 10 directly above the upper surface of the light emitting element 10 and a second region 20b located laterally from the first region 20a. A step (first step) of covering the side surface of the light emitting element 10 and the lower surface of the second region 20b of the translucent member with the light guide member 30 to provide the translucent member 20 including the light guide member 20 and the light guide member. A step (second step) of covering the outer surface of the 30 with the light reflecting member 40 is provided. Here, the translucent member 20 contains a fluorescent substance 25 and a light scattering material 28 that is not a fluorescent substance, and the concentration of the fluorescent substance 25 is higher in the first region 20a than in the second region 20b. The concentration of the light scattering material 28 is higher in the second region 20b than in the first region 20a.

In the method of manufacturing the light emitting device 100 having such a configuration, the translucent member 20 is prepared by controlling the distribution of the fluorescent substance 25 and the light scattering material 28 in a suitable form, and the translucent member 20 and the light emitting element are prepared. 10 and the light guide member 30 can be connected in a suitable relationship. Therefore, it is possible to manufacture the light emitting device 100 which easily draws heat from the fluorescent substance 25 and has less unevenness in the emission chromaticity distribution with good productivity.

2A, 2B, 2C, and 2D are schematic cross-sectional views showing the first stage, the second stage, the third stage, and the fourth stage in the manufacturing method of the light emitting device 100 according to the first embodiment, respectively. Here, the first step includes the first step and the second step, and the second step includes the third step. The light emitting device 100 of the first embodiment can be manufactured with higher productivity by producing the complex 150 of the light emitting device and dividing the complex 150 of the light emitting device as follows.

As shown in FIG. 2A, the first step is the step of preparing the translucent member 20. Specifically, the translucent member 20 is obtained by, for example, producing a sheet member 209 containing a fluorescent substance 25 and a light scattering material 28, and dividing the sheet member 209. That is, the sheet member 209 is a composite of the translucent member 20. In the first stage of the first embodiment, the translucent member 20 is prepared as a part of the sheet member 209. In order to produce the sheet member 209, it is preferable to prepare one or both of the first element sheet containing the fluorescent substance 25 and the second element sheet containing the light scattering material 28 in advance. As a result, it becomes easy to control the distribution of the fluorescent substance 25 and the light scattering material 28 in the sheet member 209 and thus in the translucent member 20 into a suitable form, and it becomes easy to prepare the translucent member 20 with good productivity. In particular, it is preferable to mold the element sheet using a mold. As a result, the distribution of the fluorescent substance 25 and the light scattering material 28 in the sheet member 209 and thus in the translucent member 20 can be easily controlled by a suitable form, and the translucent member 20 can be easily prepared with higher productivity. Further, when joining two element sheets, it is necessary that the main material of at least one (preferably both) of the two element sheets is not completely cured or solidified, that is, the joining strength of the element sheets and / or the sheet. It is preferable from the viewpoint of suppressing strain in the member 209. Further, the boundary, that is, the interface between the two joined element sheets in the sheet member 209 may be observed, but it is preferable that they are not observed from the same viewpoint. The "state not completely cured or solidified" is a state in which curing or solidification has progressed halfway, and is, for example, a state called semi-curing, B stage, gel-like, semi-solidifying, or the like. .. Further, as shown in FIG. 2A, the first and second element sheets are not limited to the undulating shape, and the shape can be appropriately selected as long as a predetermined distribution of the fluorescent substance 25 and the light scattering material 28 is obtained after joining.

As shown in FIG. 2B, the second step is to provide the translucent member 20 above the light emitting element 10 via the light guide member 30. Specifically, first, the liquid material 301 of the light guide member is applied to one or both of the light emitting element 10 and the translucent member 20 (the sheet member 209 in the first embodiment). Then, after connecting the light emitting element 10 and the translucent member 20 via the liquid material 301 of the light guide member, the liquid material 301 of the light guide member is cured or solidified. When the liquid material 301 of the light guide member is applied to the translucent member 20, the liquid material of the light guide member is placed on a region containing a high concentration of the fluorescent substance 25 of the translucent member 20 which is the first region 20a. After applying 301, the main light emitting surface (later to be the upper surface) of the light emitting element 10 is connected to the liquid material 301 of the light guide member. When the liquid material 301 of the light guide member is applied to the light emitting element 10, the liquid material 301 of the light guide member is applied to the main light emitting surface (later to be the upper surface) of the light emitting element 10, and then the light guide member. A region containing a high concentration of the fluorescent substance 25 of the translucent member 20 which is the first region 20a is connected to the liquid material 301 of the above. At this time, the liquid material 301 of the light guide member is made to reach the second region 20b and crawl up to the side surface of the light emitting element 10. As a method for applying the liquid material 301 of the light guide member, a dispensing method, a transfer method, a dipping method, or the like can be used. Further, of the two main surfaces (upper surface / lower surface in FIG. 2B) of the translucent member 20 (sheet member 209 in the first embodiment), the surface to which the light emitting element 10 is connected may be any, but is a fluorescent substance. It is preferable to use the surface on the side where the concentration of 25 is high. As a result, the heat generated by the fluorescent substance 25 can be easily drawn through the light emitting element 10. Further, it is preferable that the fluorescent substance 25 can be easily protected by keeping it away from the external environment, and a highly reliable light emitting device can be obtained even when the fluorescent substance 25, which is weak against moisture or the like, is used, for example.

As shown in FIG. 2C, the third step is to cover the outer surface of the light guide member 30 with the light reflecting member 40. Specifically, the liquid material 401 of the light-reflecting member is applied to the outer surface of the light guide member 30 to be cured or solidified. In the first embodiment, the outer surface of the light guide member 30 of the plurality of light emitting elements 10 is continuously covered to form a complex 409 of the light reflecting member. At this time, the liquid material 401 of the light-reflecting member is brought to the surface opposite to the main light-emitting surface of the light-emitting element 10 (the surface that later becomes the lower surface of the light-emitting device, excluding the positive and negative electrodes). Is preferable. The light reflecting member 40 continuously covers from the outer surface of the light guide member 30 to the surface opposite to the main light emitting surface of the light emitting element 10 (the surface that later becomes the lower surface and excluding the positive and negative electrodes). Therefore, the efficiency of extracting light in the main light emitting direction can be improved. The light reflective member 40 can be formed by compression molding, transfer molding, injection molding, potting, or the like. In order to expose the electrode 50 from the light-reflecting member 40, the amount of the light-reflecting member 40 was adjusted to be small, the light-reflective member 40 was formed to be large and then ground, or the surface of the electrode 50 was masked. The light reflective member 40 is formed in this state.

As shown in FIG. 2D, the fourth step is the step of dividing the complex 150 of the light emitting device. Specifically, the light emitting device 100 is formed by cutting a predetermined position of the light emitting device complex 150, that is, a laminated region of the sheet member 209 between the light emitting elements 10 and the light reflecting member complex 409 in a linear or lattice shape. Individualize. For example, a dicer, an ultrasonic cutter, a Thomson blade, or the like can be used for cutting the complex 150 of the light emitting device. When the light emitting devices 100 are manufactured separately one by one, the fourth step can be omitted.

<Embodiment 2>
FIG. 3A is a schematic top view of the light emitting device 200 according to the second embodiment. FIG. 3B is a schematic cross-sectional view taken along the line CC of the light emitting device 200 shown in FIG. 3A. FIG. 3C is a schematic cross-sectional view taken along the line DD of the light emitting device 200 shown in FIG. 3A. Hereinafter, the differences between the light emitting device 200 and the light emitting device 100 of the first embodiment will be described in detail, and the points substantially the same as those of the light emitting device 100 of the first embodiment will be omitted as appropriate.

As shown in FIGS. 3B and 3C, in the light emitting device 200 of the second embodiment, the second region 22b includes a fluorescent substance-containing region 22c and a fluorescent substance-free region 22d located laterally from the fluorescent substance-containing region 22c. have. That is, this is a state in which the distribution range of the fluorescent substance 25 in the second region 22b is biased toward the light emitting element 10. As a result, in the second region 22b, the heat generation region due to the fluorescent substance 25 and the non-heat generation region can be clearly separated laterally, and promotion of heat drawing from the heat generation region to the non-heat generation region can be expected. The boundary between the fluorescent substance-containing region 22c and the fluorescent substance-free region 22d is most preferably parallel to the thickness direction of the translucent member 22, that is, the Z direction, but it is inside or outside depending on the processing accuracy in manufacturing and the like. Inclinations of 10 ° or less to are included. The fluorescent substance-containing region 22c is continuous in the first region 22a. In particular, in the example shown in FIGS. 3B and 3C, the fluorescent substance-containing region 22c covers the entire area of the first region 22a. Further, in the example shown in FIGS. 3B and 3C, the concentration of the fluorescent substance 25 in the fluorescent substance-containing region 22c is uniform over the entire area, but may vary depending on the location. For example, the concentration of the fluorescent substance 25 in the fluorescent substance-containing region 22c in the first region 22a may be higher than the concentration of the fluorescent substance 25 in the fluorescent substance-containing region 22c in the second region 22b.

Further, the fluorescent substance 25 may not be contained in the second region 22b. As a result, heat generation in the second region 22b is most likely to be suppressed, and deterioration of the second region 22b due to heat can be further suppressed.

As shown in FIGS. 3B and 3C, in the light emitting device 200 of the second embodiment, the light guide member 32 contains the second fluorescent substance 26. As a result, it is easy to make up for the shortage of the fluorescent substance 25 in the second region 22b and suppress the unevenness of the emission chromaticity distribution. In particular, it is suitable when the second region 22b has a fluorescent substance-free region 22d. In the examples shown in FIGS. 3B and 3C, the concentration of the second fluorescent substance 26 in the light guide member 32 is higher on the lower side than on the upper side. As a result, heat generation in the upper part of the light guide member 32, that is, on the side of the second region 22b is suppressed, and heat generated by the fluorescent substance 25, particularly heat in the second region 22b, can be easily drawn to the light guide member 32. Further, when the upper surface of the light emitting element 10 is the surface of the substrate 11 as described above, the heat generated by the second fluorescent substance 26 can be easily attracted to the lower surface side and the semiconductor laminate 15 side.

As shown in FIGS. 3A to 3C, in the light emitting device 200 of the second embodiment, the side surface of the translucent member 22 is covered with the light reflecting member 42. As a result, it is possible to suppress the leakage of light from the translucent member 22 to the side, and it is easy to suppress the unevenness of the emission chromaticity distribution. Further, heat can be expected from the second region 22b to the light reflecting member 42. From this viewpoint, it is preferable that the light reflecting member 42 covers 1/2 or more of the area of the side surface of the translucent member 22 in the thickness direction of the translucent member 22, and the side surface of the translucent member 22. It is more preferable to cover 3/4 or more of the area of the light-transmitting member 22, and it is even more preferable to cover the entire side surface of the translucent member 22. As in the light emitting device 100 of the first embodiment, the entire side surface of the translucent member 20 is exposed from the light reflecting member 40, that is, a part of the side surface of the light emitting device 100 is formed. You may. In that case, it is easy to increase the light extraction efficiency.

(Manufacturing method of light emitting device 200)
4A, 4B, 4C, and 4D are schematic cross-sectional views showing the first stage, the second stage, the third stage, and the fourth stage in the manufacturing method of the light emitting device 200 according to the second embodiment, respectively. Hereinafter, the points different from the manufacturing method of the light emitting device 100 of the first embodiment in the manufacturing method of the light emitting device 200 will be described in detail, and the points substantially the same as the manufacturing method of the light emitting device 100 of the first embodiment will be described. The description will be omitted as appropriate.

As shown in FIG. 4A, the first step is the step of preparing the translucent member 22. Specifically, the translucent member 22 is obtained by, for example, producing a sheet member 229 containing the fluorescent substance 25 and the light scattering material 28, and dividing the sheet member 229. That is, the sheet member 229 is a composite of the translucent member 22. Then, in the first stage of the second embodiment, the translucent member 22 is prepared by dividing the sheet member 229 into a block shape before connecting the sheet member 229 to the light emitting element 10. In order to prepare the sheet member 229, one of a plurality of blocks containing the fluorescent substance 25 and a plurality of sheets with openings (for example, a grid-like sheet) containing the light scattering material 28 may be prepared in advance. preferable. As a result, it becomes easy to control the distribution of the fluorescent substance 25 and the light scattering material 28 in the sheet member 229 into a suitable form, and it becomes easy to prepare the translucent member 22 with good productivity. When a block containing fluorescent substance 25 is produced, a plurality of blocks containing fluorescent substance 25 are juxtaposed on an adhesive sheet or the like so as to be separated from each other, and a liquid material containing a light scattering material 28 is filled in the separated region. The sheet member 229 can be manufactured by curing or solidifying the sheet member 229. When a sheet with an opening containing the light scattering material 28 is produced, a sheet with an opening containing the light scattering material 28 is placed on an adhesive sheet or the like, and a liquid material containing the fluorescent substance 25 is filled in each opening and cured. Alternatively, the sheet member 229 can be manufactured by solidifying. For example, a dicer, an ultrasonic cutter, a Thomson blade, or the like can be used for cutting the sheet member 229.

As shown in FIG. 4B, the second step is to provide the translucent member 22 above the light emitting element 10 via the light guide member 32. Specifically, first, the liquid material 321 of the light guide member is applied to one or both of the light emitting element 10 and the translucent member 22. Then, after connecting the light emitting element 10 and the translucent member 22 via the liquid material 321 of the light guide member, the liquid material 321 of the light guide member is cured or solidified. When the liquid material 321 of the light guide member is applied to the translucent member 22, the liquid material of the light guide member is placed on a region containing a high concentration of the fluorescent substance 25 of the translucent member 22 which is the first region 22a. After applying 321, the upper surface of the light emitting element 10 is connected to the liquid material 321 of the light guide member. When the liquid material 321 of the light guide member is applied to the light emitting element 10, the liquid material 321 of the light guide member is applied to the upper surface of the light emitting element 10, and then the first region 22a is applied to the liquid material 321 of the light guide member. A region containing a high concentration of the fluorescent substance 25 of the translucent member 22 is connected. At this time, the liquid material 321 of the light guide member is made to reach the second region 22b and crawl up to the side surface of the light emitting element 10. Further, the second fluorescent substance 26 can be settled by gravity or centrifugal force until the liquid material 321 of the light guide member is completely cured or solidified, and the second fluorescent substance 26 can be unevenly distributed in a desired direction. ..

As shown in FIG. 4C, the third step is to cover the outer surface of the light guide member 32 with the light reflecting member 42. Specifically, the liquid material 421 of the light-reflecting member is applied to the outer surface of the light guide member 32 to be cured or solidified. In the second embodiment, the outer surface of the light guide member 32 of the plurality of light emitting elements 10 is continuously covered to form a composite 429 of the light reflecting member. At this time, the liquid material 421 of the light-reflecting member is brought to the side surface of each translucent member 22. In order to expose the main light emitting surface of the light-transmitting member 22 from the light-reflecting member 42, the amount of the light-reflecting member 42 may be adjusted to be small, or the light-reflecting member 42 may be formed to be large and then ground. The light reflective member 42 may be formed while the main light emitting surface of the translucent member 22 is masked.

As shown in FIG. 4D, the fourth step is the step of dividing the complex 250 of the light emitting device. Specifically, the light emitting device 200 is formed by cutting a predetermined position of the light emitting device complex 250, that is, a region composed of the light reflecting member complex 429 between the translucent members 22 in a linear or lattice shape. Individualize.

Hereinafter, each component of the light emitting device according to the embodiment of the present invention will be described.

(Light emitting element 10)
The light emitting element is preferably a semiconductor light emitting element, but may be an organic EL element. Examples of the semiconductor light emitting device include an LED (light emitting diode) chip. The semiconductor light emitting device may have at least a semiconductor laminate constituting the light emitting device structure, and may further have a substrate. The top view shape of the light emitting element is preferably a rectangular shape, particularly a square shape or a rectangular shape long in one direction. The side surface of the light emitting element or the substrate thereof may be perpendicular to the upper surface, or may be inclined inward or outward. The light emitting element preferably has positive and negative (p, n) electrodes on the same surface side. When the light emitting element is a flip chip (face down) mounting type, the main light emitting surface is a surface opposite to the electrode forming surface. The number of light emitting elements mounted on one light emitting device may be one or a plurality. A plurality of light emitting elements can be connected in series or in parallel. When a plurality of light emitting elements are connected to one translucent member, the region located directly above the upper surface of each light emitting element in the translucent member is set as the first region, and is lateral to the first region. A region located in, that is, a region other than the first region can be considered as a second region.

(Board 11)
The substrate is preferably a crystal growth substrate capable of growing semiconductor crystals, but may be a bonding substrate to be separately bonded to a semiconductor laminate separated from the crystal growth substrate. Since the substrate has translucency, it is easy to adopt flip-chip mounting, and it is easy to improve the light extraction efficiency. As the substrate, one of sapphire, gallium nitride, aluminum nitride, silicon, silicon carbide, gallium arsenic, gallium phosphorus, indium phosphorus, zinc sulfide, zinc selenium, and glass can be used. Among them, sapphire is preferable because it has excellent translucency and is easily available at a relatively low cost as a substrate for crystal growth of a nitride semiconductor. Further, gallium nitride is suitable as a substrate for crystal growth of a nitride semiconductor, and is preferable in that it has relatively high thermal conductivity. The thickness of the substrate can be appropriately selected, but is preferably 50 μm or more and 500 μm or less, and more preferably 80 μm or more and 300 μm or less, from the viewpoint of light extraction efficiency, mechanical strength, and the like.

(Semiconductor laminate 15)
The semiconductor laminate preferably includes at least an n-type semiconductor layer and a p-type semiconductor layer, with an active layer interposed therebetween. As the semiconductor material, it is preferable to use a nitride semiconductor capable of efficiently emitting short wavelength light that easily excites a fluorescent substance. Nitride semiconductors are mainly represented by the general formula InxAlyGa1-x-yN (0≤x, 0≤y, x + y≤1). In addition, zinc sulfide, zinc selenide, silicon carbide and the like can also be used. The emission peak wavelength of the light emitting element is preferably in the blue region, and more preferably in the range of 450 nm or more and 475 nm or less, from the viewpoint of luminous efficiency, excitation of the fluorescent substance, and a color mixing relationship with the emission thereof. The thickness of the semiconductor laminate can be appropriately selected, but from the viewpoint of luminous efficiency, crystallinity, etc., it is preferably 1 μm or more and 10 μm or less, and more preferably 3 μm or more and 10 μm or less.

(Translucent members 20, 22)
The translucent member has a function of transmitting the light of the light emitting element to the outside of the device while protecting the light emitting element from outside air and external force together with the light guide member and the light reflective member. The translucent member has at least a translucent main material, and further contains a fluorescent substance in the main material. It is preferable that the top view shape of the translucent member is larger than the light emitting element and mathematically similar to the top view shape of the light emitting element in terms of luminous intensity distribution, chromaticity distribution, and the like. If the upper surface and / or the lower surface of the translucent member is a flat surface, the productivity is good, and if the surface has irregularities or a curved surface, the light extraction efficiency can be improved. The translucent member may be composed of a single layer or a laminated body of a plurality of layers in the thickness direction thereof. When the translucent member is composed of a laminated body, different types of main materials may be used for each layer, or different types of fluorescent substances may be contained in each layer. Further, since the outermost layer is a layer that does not contain a fluorescent substance, deterioration of the fluorescent substance due to outside air or the like can be suppressed. The thickness of the translucent member can be appropriately selected, but is preferably 50 μm or more and 500 μm or less, and more preferably 80 μm or more and 300 μm or less, from the viewpoint of light extraction efficiency, the content of the fluorescent substance, and the like.

(Main material of translucent member)
As the main material of the translucent member, at least one of silicone resin, epoxy resin, phenol resin, polycarbonate resin, acrylic resin, modified resin thereof, and glass can be used. Among them, a silicone resin or a modified resin thereof is preferable because it is excellent in heat resistance and light resistance. Specific examples of the silicone resin include dimethyl silicone resin, phenyl-methyl silicone resin, and diphenyl silicone resin. In particular, the inclusion of a phenyl group enhances heat resistance and gas barrier properties. The content of the phenyl group among all the organic groups bonded to the silicon atom in the silicone resin or the modified resin thereof is preferably 10 mol% or more and 70 mol% or less, and more preferably 20 mol% or more and 60 mol% or less. The "modified resin" in the present specification includes a hybrid resin.

(Fluorescent substances 25, 26)
The fluorescent substance absorbs at least a part of the light (primary light) emitted from the light emitting element and emits light having a wavelength different from that of the primary light (secondary light). This makes it possible to obtain a light emitting device that emits a mixed color light of primary light and secondary light having a visible wavelength, such as white light. In the case of a light emitting device that emits white light, it is preferable that the emission chromaticity range conforms to the ANSI C78.377 standard. The content of the fluorescent substance in the translucent member can be appropriately selected according to the desired chromaticity of emission, but is preferably 40 parts by weight or more and 250 parts by weight or less, and 70 parts by weight or more and 150 parts by weight or less. Is more preferable. The "part by weight" represents the weight (g) of the particles to be blended with respect to the weight of the main material of 100 g. The emission peak wavelength of the fluorescent substance that emits green light is preferably in the range of 520 nm or more and 560 nm or less from the viewpoint of luminous efficiency and color mixing relationship with the light of another light source. Specifically, examples of the fluorescent substance that emits green light include an yttrium-aluminum-garnet-based fluorescent substance (for example, Y3 ₍ Al, Ga) ₅ O ₁₂ : Ce) and a terbium-aluminum-garnet-based fluorescent substance (for example, Lu ₃ (for example)). Al, Ga) ₅ O ₁₂ : Ce), terbium-aluminum-garnet-based fluorescent material (for example, Tb ₃ (Al, Ga) ₅ O ₁₂ : Ce) -based fluorescent material, silicate-based fluorescent material (for example, (Ba, Sr) ₂ ) SiO ₄ : Eu), chlorosilicate-based fluorescent material (for example, Ca ₈ Mg (SiO ₄ ) _{4 Cl2} : Eu), β-sialon-based fluorescent material (for example, Si _6-Z Al _Z O _Z N _8-Z : Eu (0) <z <4.2)), SGS-based phosphors (for example, SrGa ₂ S ₄ : Eu) and the like can be mentioned. Examples of the fluorescent substance that emits yellow light include α-sialon-based phosphors (for example, Mz (Si, Al) ₁₂ (O, N) ₁₆ (where 0 <z ≦ 2), where M is Li, Mg, Ca, Y, and (Lantanide element excluding La and Ce) and the like. In addition, among the above-mentioned fluorescent substances that emit green light, there is also a fluorescent substance that emits yellow light. For example, the yttrium-aluminum-garnet-based fluorescent substance is one of Y. By substituting the part with Gd, the emission peak wavelength can be shifted to the long wavelength side, and yellow emission is possible. In addition, some fluorescent substances capable of orange emission are also red emission. The emission peak wavelength of the fluorescent substance is preferably in the range of 620 nm or more and 670 nm or less from the viewpoint of emission efficiency and color mixing relationship with the light of other light sources. Specifically, the fluorescent substance that emits red light contains nitrogen. Calcium alminosilicate (CASN or SCASN) -based phosphors (eg, (Sr, Ca) AlSiN ₃ : Eu) and the like can be mentioned. In addition, manganese-activated fluoride-based phosphors (general formula (I) A ₂ [M _1- ]. _a Mn _a F ₆ ] is a fluorescent substance (however, in the above general formula ₍ I), A is at least one selected from the group consisting of K, Li, Na, Rb, Cs and NH4. Yes, M is at least one element selected from the group consisting of Group 4 elements and Group 14 elements, and a is 0 <a <0.2)). As a typical example of the system fluorescent substance, there is a fluorescent substance of manganese _- activated potassium fluoride silicate (for example, K2 SiF ₆ : Mn). As the fluorescent substance, one of the above specific examples may be used alone or two of them. The above can be used in combination. For example, the fluorescent substance may be composed of a phosphor that emits green light or yellow light and a fluorescent substance that emits red light. With such a configuration, color reproducibility or color development may occur. However, on the other hand, the amount of the fluorescent substance used increases and the heat generation increases accordingly, so that the configuration of the light emitting device of the present embodiment becomes effective. In particular, the phosphor that emits red light is preferably a manganese-activated fluoride-based fluorescent substance. The manganese-activated fluoride-based fluorescent substance can emit light having a narrow spectral half-value width in the red region, but the emission efficiency is compared. Since the target is low, the amount used tends to increase, and the heat generation tends to increase accordingly. Therefore, the configuration of the light emitting device of the present embodiment is more likely to be effective.

(Light Scattering Material 28)
The light scattering material may be an organic substance, but an inorganic substance having excellent heat resistance and light resistance is preferable. Further, if it is an inorganic substance, it can easily function as a filler for adjusting the thermal conductivity, the coefficient of thermal expansion, and the like of the translucent member. As a specific inorganic substance, at least one of silicon oxide, titanium oxide, magnesium oxide, zinc oxide, aluminum oxide, zirconium oxide, calcium carbonate and barium sulfate is preferable. Of these, magnesium oxide, zinc oxide, and aluminum oxide are preferable in terms of thermal conductivity. Further, silicon oxide, titanium oxide and zirconium oxide are preferable because they are relatively inexpensive and easily available. If it is an organic substance, there is an advantage that the optical characteristics can be adjusted by copolymerization or the like. Specific organic substances include polymethacrylic acid ester and its copolymer, polyacrylic acid ester and its copolymer, crosslinked polymethacrylic acid ester, crosslinked polyacrylic acid ester, polystyrene and its copolymer, crosslinked polystyrene, and silicone. Resins and modified resins thereof are preferred. As the light scattering material, one of these can be used alone, or two or more of these can be used in combination. The content of the light scattering material in the translucent member can be appropriately selected, but is preferably 1 part by weight or more and 100 parts by weight or less, and more preferably 5 parts by weight or more and 50 parts by weight or less. The shape of the light scattering material can be appropriately selected and may be crushed (atypical), but a spherical shape is preferable in terms of filling property and suppression of aggregation.

(Light guide members 30, 32)
The light guide member has translucency, and in addition to guiding the light of the light emitting element to the translucent member, the light emitting element and the translucent member can be adhered to each other. The outer surface of the light guide member, that is, the interface with the light reflecting member is preferably inclined or curved with respect to the side surface of the light emitting element and the lower surface of the light transmissive member from the viewpoint of light extraction efficiency. As the main material of the light guide member, at least one of silicone resin, epoxy resin, phenol resin, polycarbonate resin, acrylic resin, modified resin thereof, and glass can be used. Among them, a silicone resin or a modified resin thereof is preferable because it is excellent in heat resistance and light resistance. Specific examples of the silicone resin include dimethyl silicone resin, phenyl-methyl silicone resin, and diphenyl silicone resin. In particular, the inclusion of a phenyl group enhances heat resistance and gas barrier properties. The content of the phenyl group among all the organic groups bonded to the silicon atom in the silicone resin or the modified resin thereof is preferably 10 mol% or more and 70 mol% or less, and more preferably 20 mol% or more and 60 mol% or less. The light guide member may contain various fillers in the main material in order to adjust the thermal conductivity, the coefficient of thermal expansion, and the like. As the filler, the same filler as the above-mentioned inorganic light scattering material can be used.

(Light reflective members 40, 42)
The light-reflecting member is preferably white from the viewpoint of light extraction efficiency. Therefore, it is preferable that the light-reflecting member contains a white pigment in the main material. As the main material of the light-reflecting member, at least one of silicone resin, epoxy resin, phenol resin, polycarbonate resin, acrylic resin, modified resin thereof, and glass can be used. Among them, a silicone resin or a modified resin thereof is preferable because it is excellent in heat resistance and light resistance. Specific examples of the silicone resin include dimethyl silicone resin, phenyl-methyl silicone resin, and diphenyl silicone resin. In particular, the inclusion of a phenyl group enhances heat resistance and gas barrier properties. The content of the phenyl group among all the organic groups bonded to the silicon atom in the silicone resin or the modified resin thereof is preferably 10 mol% or more and 70 mol% or less, and more preferably 20 mol% or more and 60 mol% or less. White pigments include titanium oxide, zinc oxide, magnesium oxide, magnesium carbonate, magnesium hydroxide, calcium carbonate, calcium hydroxide, calcium silicate, magnesium silicate, barium titanate, barium sulfate, aluminum hydroxide, aluminum oxide, and zirconium oxide. One of them can be used alone, or two or more of them can be used in combination. Of these, titanium oxide is preferable because it has excellent light reflectivity and is relatively inexpensive to obtain. The content of the white pigment in the light-reflecting member can be appropriately selected, but is preferably 20 parts by weight or more and 300 parts by weight or less, preferably 50 parts by weight or more, from the viewpoint of light reflectivity and viscosity when used as a liquid material. It is more preferably 200 parts by weight or less.

(Electrode 50)
The electrode may be the positive or negative electrode of the light emitting element itself, or may be separately provided by being connected to the positive and negative electrodes of the light emitting element. Examples of the separately provided electrode include bumps, pillars, and lead electrodes (individualized lead frames). The electrodes can be made of small pieces of metal or alloy. Specifically, at least one of gold, silver, copper, iron, tin, platinum, zinc, rhodium, titanium, nickel, palladium, aluminum, tungsten, chromium, molybdenum and alloys thereof can be used. Among them, copper or a copper alloy is particularly preferable because copper has excellent thermal conductivity and is relatively inexpensive. Further, gold or a gold alloy is also preferable because gold is chemically stable, has little surface oxidation, and has a property of being easily bonded. The electrode may have a gold or silver coating on the surface from the viewpoint of solder bondability.

As described above, the light emitting device of the first and second embodiments is an example of the top light emitting (top view) type, but the side light emitting (side view) type may be used depending on the arrangement relationship of the electrodes (terminals) with respect to the main light emitting direction. can. The mounting direction of the top light emitting device is substantially parallel to the main light emitting direction and is opposite to the main light emitting direction. For example, the mounting direction of the light emitting device of the first and second embodiments is downward. On the other hand, the mounting direction of the side light emitting type light emitting device is substantially perpendicular to the main light emitting direction. Further, the light emitting device of the first and second embodiments is an example of a light emitting device not provided with a mounting board on which the light emitting element is mounted, but the present invention is not limited to this, and the light emitting element is mounted on the mounting board. It may be a light emitting device. In that case, a light emitting element bonded by solder or the like is used on the wiring of the mounting board in the second stage (FIGS. 2B and 4B), and the light reflecting member is mounted on the mounting board in the third stage (FIGs. 2C and 4C). To form. After that, if the mounting substrate is in the form of a composite, the mounting substrate may be cut together with the sheet member, the light-reflecting member, and the like in the fourth stage (FIGS. 2D and 4D).

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

<Example 1>
The light emitting device of the first embodiment has the structure of the light emitting device 100 of the examples shown in FIGS. 1A to 1C, and is a rectangular parallelepiped top light emitting / CSP type LED having a width of 1.7 mm, a depth of 1.7 mm, and a thickness of 0.28 mm. It is a device. The light emitting element 10 is a square-shaped LED chip having a width of 1 mm, a depth of 1 mm, and a thickness of 0.155 mm, capable of emitting blue light at a light emitting peak wavelength of 455 nm. The light emitting element 10 has a sapphire substrate 11 and a semiconductor laminate 15 in which an n-type semiconductor layer, an active layer, and a p-type semiconductor layer of a nitride semiconductor are sequentially laminated in contact with the lower surface of the substrate 11. There is. The translucent member 20 is connected above the light emitting element 10 via the light guide member 30. The translucent member 20 is a small piece of a fluorescent substance-containing resin sheet having a width of 1.7 mm, a depth of 1.7 mm, and a thickness of 0.1 mm and having a square shape when viewed from above. It is assumed that the centers and orientations of the light emitting element 10 and the translucent member 20 in the top view are the same (however, manufacturing errors are included). The translucent member 20 is composed of the following two layers, an upper layer and a lower layer. However, the boundary between the upper layer and the lower layer is not observed. The lower layer is a cured product of a phenyl-methyl silicone resin containing a β-sialon-based fluorescent substance and a manganese-activated fluoride-based fluorescent substance as the fluorescent substance 25. The upper layer is a cured product of a phenyl-methyl silicone resin containing spherical particles of aluminum oxide having an average particle size of 20 to 25 nm as a light scattering material 28. The lower layer gradually becomes thicker from the side edge of the second region 20b toward the center of the first region 20a. The fluorescent substance 25 is distributed over the entire lower layer at an equivalent concentration (volume concentration 25%). Therefore, the concentration of the fluorescent substance 25 in the translucent member 20 is the lowest at the side end portion of the second region 20b and the highest at the central portion of the first region 20a. On the other hand, the upper layer gradually becomes thicker as it approaches the side edge of the second region 20b from the center of the first region 20a. The light scattering material 28 is distributed over the entire upper layer at an equivalent concentration (volume concentration 4.5%). Therefore, the concentration of the light scattering material 28 in the translucent member 20 is the lowest in the central portion of the first region 20a and the highest in the side end portion of the second region 20b. The light guide member 30 covers the upper surface of the light emitting element 10 and the lower surface of the first region 20a of the translucent member, and the four side surfaces of the light emitting element 10 and the lower surface of the second region 20b of the translucent member. The outer surface of the light guide member 30 is inclined or curved with respect to the side surface of the light emitting element 10 and the lower surface of the second region 20b of the translucent member. The light guide member 30 is a cured product of a phenyl-methyl silicone resin that does not contain a fluorescent substance. The light reflecting member 40 covers the outer surface of the light guide member 30 on the side of the light emitting element 10, and covers the region on the lower surface of the light emitting element 10 excluding the positive and negative electrodes below the light emitting element 10. If the light guide member 30 does not cover a part (lower part) of the side surface of the light emitting element 10, the light reflecting member 40 covers a part (lower part) of the side surface of the light emitting element 10. The light reflective member 40 is a cured product of a phenyl-methyl silicone resin containing 150 parts by weight of titanium oxide. An electrode 50 is connected to each of the positive and negative electrodes formed on the lower surface of the semiconductor laminate 15 of the light emitting element. The electrode 50 is a small piece of copper with a nickel / gold coating and a thickness of 0.025 mm. The lower surface of the pair of electrodes 50, that is, the surface of the gold coating, is exposed from the light-reflecting member 40. More specifically, the lower surface of the light emitting device is composed of the lower surface of the light reflecting member 40 and the lower surface of the pair of electrodes 50.

The light emitting device of the first embodiment is manufactured by producing a light emitting device complex 150 and dividing the light emitting device complex 150 by a dicing device as follows. First, the first element sheet in a semi-cured state, which periodically contains a distribution close to the thickness distribution of the fluorescent substance 25 in the lower layer, and a distribution close to the light scattering material 28 in the upper layer and the thickness distribution. The sheet member 209 is manufactured by crimping the second element sheet in a semi-cured state, which periodically contains the above-mentioned light in the vertical and horizontal directions, and completely curing the light. Next, the liquid material 301 of the light guide member is applied by pin transfer on each region of the sheet member 209 containing the fluorescent substance 25 at a high concentration. Next, the substrate 11 side of the light emitting element 10 in which small pieces of copper are connected to the positive and negative electrodes is placed on the liquid material 301 of each light guide member coated on the sheet member 209. At this time, the pushing amount of the light emitting element 10 is adjusted so that the liquid material 301 of the light guide member is wetted and spread on the sheet member 209 and crawls up on the four side surfaces of the light emitting element 10. Then, the liquid material 301 of the light guide member is cured in the oven. Next, the liquid material 401 of the light-reflecting member is filled and cured by a compression molding method so as to embed all the light emitting elements 10. Then, the obtained composite complex 409 of the light-reflecting member is ground to expose small pieces of copper. Then, a nickel / gold film is formed on the exposed surface of each small piece of copper by a sputtering device to form an electrode 50. Finally, the complex 150 of the light emitting device obtained as described above is cut in a grid pattern.

The light emitting device of the first embodiment configured as described above can exhibit the same effect as the light emitting device 100 of the first embodiment.

The light emitting device according to the embodiment of the present invention includes a backlight device for a liquid crystal display, various lighting fixtures, a large display, various display devices such as advertisements and destination guides, a projector device, a digital video camera, a facsimile, and a copy. It can be used as an image reading device in a machine, a scanner, or the like.

10 Light emitting element 11 Substrate 15 Semiconductor laminate 20, 22 Translucent member 20a, 22a First region 20b, 22b Second region 22c Fluorescent substance-containing region 22d Fluorescent substance-free region 25, 26 Fluorescent material 28 Light scattering material 30, 32 Light guide member 40, 42 Light reflective member 50 Electrode 100, 200 Light emitting device 209,229 Sheet member 301,321 Liquid material for light guide member 401,421 Liquid material for light reflective member 409,429 Light reflective member Complex 150,250 Complex of light emitting device

Claims (10)

A translucent member including only a first region located directly above the upper surface of the light emitting element and a second region located lateral to the first region above the light emitting element is designated as a side surface of the light emitting element. The first step of providing the translucent member so that the lower surface of the first region and a part of the lower surface of the second region are covered with the light guide member.
A second step of covering the outer surface of the light guide member and the lower surface of the second region exposed from the light guide member with a light reflecting member is provided.
The translucent member contains a fluorescent substance and a light scattering material that is not a fluorescent substance.
The concentration of the fluorescent substance is higher in the first region than the region located directly above the light guide member in the second region, and is lateral to the region of the second region located directly above the light guide member. In the first region, it is higher than the region located directly above the light-reflecting member.
A method for manufacturing a light emitting device in which the concentration of the light scattering material is higher in a region of the second region than the first region, which is located directly above the light guide member. The light emitting device according to claim 1, wherein the first step includes a step of preparing the translucent member and a step of providing the translucent member on the light emitting element via the light guide member. Production method. The second aspect of the present invention, wherein the step of preparing the translucent member includes a step of joining a preformed first element sheet containing a fluorescent substance and a second element sheet containing a light diffusing material. How to manufacture a light emitting device. The method for manufacturing a light emitting device according to claim 3, wherein the first element sheet and the second element sheet each have an undulating shape on the surface to be joined. The method for manufacturing a light emitting device according to claim 4, wherein at least one of the first element sheet and the second element sheet is molded using a mold. In the step of preparing the translucent member, a plurality of blocks containing a fluorescent substance are prepared, the plurality of blocks are arranged apart from each other, and a liquid material containing a light scattering material is filled in the separated regions. The method for manufacturing a light emitting device according to claim 2, which comprises a step of making a light emitting device. 2. The step of preparing the translucent member includes a step of preparing a sheet containing a light scattering material and having an opening, and filling the opening with a liquid material containing a fluorescent substance. The method for manufacturing a light emitting device according to the above. The method for manufacturing a light emitting device according to claim 1 to 7, wherein the fluorescent substance is not contained in the second region. The method for manufacturing a light emitting device according to claim 1 to 8, wherein the light guide member does not contain a fluorescent substance. The method for manufacturing a light emitting device according to claim 1 to 9, wherein the entire side surface of the translucent member constitutes a part of the side surface of the light emitting device.

Images