JP2009032746A - Light-emitting device and light-emitting unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light-emitting device which is reduced in thickness and can emit light forward efficiently, and a light-emitting unit equipped with the light-emitting device. <P>SOLUTION: The light-emitting device includes a package having an almost oblong light-emitting face having a recession, a back face opposite to the light-emitting face, and first and second side faces almost perpendicular to the light-emitting face and the back face and connected to the light-emitting face and the back face via long sides, and a light-emitting element disposed in the recession. The first side face has first and second feed electrode faces connected to the light-emitting element, and a mount face disposed between the first and second feed electrode faces. A level difference is formed between the first feed electrode face and the mount face and between the second feed electrode face and the mount face. The first and second feed electrode faces are retreated deeper than the mount face adjacent thereto. A second wall between the recession and the second side face is different in thickness from a first wall between the recession and the first side face. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a light emitting device and a light emitting unit, for example, a side view type light emitting device that can be used for a backlight of a liquid crystal display (LCD) and a light emitting unit equipped with the light emitting device.

  Among light-emitting devices that are used by being mounted on a mounting member such as a substrate, there is a “side-view type” light-emitting device that emits light in a direction substantially parallel to the mounting surface. Side-view light-emitting devices can be used for various purposes such as lighting, display, and signal transmission. For example, when a side-view type light emitting device is used for the backlight of a liquid crystal display, light can be incident from the side of the light guide plate constituting the backlight which is a light emitting unit, and a thin and highly efficient backlight can be realized. .

  Due to recent market trends, there is a demand for further reduction in thickness and brightness of side-view type light emitting devices. However, as the light emitting device becomes thinner and has higher brightness, the temperature of the semiconductor light emitting element to be mounted also rises, resulting in a decrease in the light emission efficiency of the semiconductor light emitting element and a decrease in the reflectance of the resin constituting the package. There is.

Thus, there is a light-emitting device that uses a ceramic package that suppresses a temperature rise by high heat dissipation and does not decrease light reflectance (for example, Patent Document 1). Alternatively, there is a thin side-view type light-emitting device that has been conventionally used for a backlight of a liquid crystal display (for example, Patent Document 2). Furthermore, there is a side-view type light emitting device that uses a ceramic package that suppresses temperature rise by high heat dissipation and does not decrease light reflectivity even at relatively high temperatures (for example, Patent Document 3).
Japanese Patent Laid-Open No. 2002-232017 JP 2004-207688 A JP 2004-228100 A

  Since ceramic has a property of transmitting light, if the thickness of the reflection surface of the ceramic package is thin, the probability that light emitted from the semiconductor light emitting element is transmitted through the ceramic increases. When the probability of light passing through the ceramic increases, the brightness of the light emitted in front of the light emitting device decreases. For example, the reflectance of a ceramic plate having a thickness of 1 mm is about 82%, whereas the reflectance of a ceramic plate having a thickness of 0.2 mm is about 65%.

  Therefore, it is desired to set the thickness of the reflection surface of the ceramic package to about 1 mm or more. However, as described above, the thickness of the light emitting surface of the light emitting device is required to be 1 mm or less due to the demand for thinning the side view type light emitting device. Along with this, the thickness of the reflecting surface becomes 0.2 mm or less. As a result, the light emitted from the semiconductor light emitting element passes through the reflecting surface and leaks in the lateral direction, which causes a problem that the light cannot be efficiently emitted in front of the light emitting device.

  The present invention has been made based on recognition of such a problem, and provides a light emitting device capable of efficiently emitting light in front of the light emitting device while reducing the thickness of the light emitting device, and a light emitting unit equipped with the light emitting device.

  According to one aspect of the present invention, a substantially rectangular light emitting surface having a recess, a back surface facing the light emitting surface, the light emitting surface and the light emitting surface substantially orthogonal to the back surface, and A package having a first side surface connected to the back surface at a long side, a second side surface facing the first side surface, and a light emitting element provided in the recess, Side surfaces of the first and second power supply electrode surfaces connected to the light emitting element, and a mounting mount surface provided between the first power supply electrode surface and the second power supply electrode surface. A step is provided between the first power supply electrode surface and the mounting mount surface, and a step is provided between the second power supply electrode surface and the mounting mount surface. The first and second power supply electrode surfaces recede from the mounting mount surface adjacent thereto, A light emitting device characterized in that a thickness of a second wall between the concave portion and the second side surface is different from a thickness of the first wall between the concave portion and the first side surface. Provided.

  According to another aspect of the present invention, a mounting substrate and the light emitting device mounted on the mounting substrate are provided, and at least one of the first and second side surfaces reflects light. There is provided a light emitting unit characterized by being covered with a material.

  ADVANTAGE OF THE INVENTION According to this invention, the light-emitting device which can radiate | emit light efficiently in front of a light-emitting device, and the light-emitting unit carrying this light-emitting device are provided, reducing a light-emitting device thinly.

  Embodiments of the present invention will be described below with reference to the drawings. In addition, in each drawing, the same code | symbol is attached | subjected to the same component and detailed description is abbreviate | omitted suitably.

FIG. 1 is a perspective view showing two specific examples of the light emitting device according to the first embodiment of the present invention. FIG. 1A shows a light emitting device having a thick wall between the recess and the upper surface. FIG. 1B is a perspective view illustrating a light emitting device having a thin wall between the recess and the upper surface.
FIG. 2 is a perspective view of the light emitting device according to the present embodiment as viewed from the rear side.
FIG. 3 is a front view of the light emitting device shown in FIG. 1A as viewed from the front side.

  The light emitting device according to the present embodiment includes a substantially rectangular parallelepiped package 1 provided with a recess 1a, and a semiconductor light emitting element 3 provided in the recess 1a. On the bottom surface of the recess 1a, land electrodes 5a, 5b, 5c, which are bottom electrodes, and lead electrodes 5d, 5e are provided. The semiconductor light emitting element 3 is mounted on the land electrodes 5a, 5b, and 5c. An electrode (not shown) provided in the semiconductor light emitting element 3 is connected to the land electrodes 5 b and 5 c and the lead electrode 5 e by bonding wires 4. In the case of the specific example shown in FIG. 1, three semiconductor light emitting elements 3 are mounted in the recess 1a, and these semiconductor light emitting elements are connected in series. Similarly, the land electrode 5a and the lead electrode 5d are connected by the bonding wire 4. And the recessed part 1a is sealed with translucent resin 16 (refer FIG. 4), such as an epoxy and silicone.

4 is a schematic cross-sectional view of the light-emitting device shown in FIG. 3, FIG. 4 (a) is a schematic view showing the AA ′ cross-section, and FIG. 4 (b) is a cross-section BB ′. FIG.
FIG. 5 is a schematic view illustrating the state of the internal wiring of the light emitting device according to this embodiment. FIG. 5A shows the state of the internal wiring of the light emitting device in which the internal wiring is provided only on the upper side. FIG. 5B is a schematic view illustrating the state of the internal wiring of the light emitting device in which the internal wiring is provided only on the lower side.

  The land electrodes 5a, 5b, and 5c and the lead electrodes 5d and 5e are provided inside the package 1 while being insulated from each other. The lead electrodes 5 d and 5 e extend to the left and right ends of the package 1 and are connected to a mounting mount surface electrode 2 a provided on the outer surface of the package 1. That is, the mounting mount surface electrodes 2a at the left and right ends of the package 1 are connected to the land electrodes 5a, 5b, 5c and the electrodes of the semiconductor light emitting element 3 through the lead electrodes 5d, 5e and the bonding wires 4. Yes.

The recess 1 a is provided on the front surface 1 b corresponding to the light emitting surface of the package 1. On the side surface substantially orthogonal to the front surface 1b, a pair of mounting mount surface electrodes 2a (feeding electrode surfaces) are provided at the left and right ends, and a mounting mount surface 1m is provided between the mounting mount surface electrodes 2a. The light emitting device of this embodiment is mounted such that the mounting mount surface 1m faces a circuit board (not shown).
At the left and right ends of the front surface 1b corresponding to the light emitting surface of the package 1, light emitting surface electrodes 2b are provided. At the left and right ends of the upper surface 1c of the package 1, upper surface electrodes 2c are provided, and at the left and right ends of the rear surface 1d of the package 1, rear electrodes 2d are provided. Furthermore, a heat radiating member 9 is provided on the rear surface 1d of the package 1 (see FIGS. 2 and 4). The heat dissipating member 9 is preferably made of a highly heat conductive material and further has high reflection characteristics.

  The package 1 can be formed of ceramic such as alumina or mullite, glass ceramic, glass epoxy, paper phenol, other thermosetting resin, UV (ultraviolet) curable resin, or thermoplastic resin. The side surface of the recess 1a can be a light reflecting surface. That is, the light emitted from the semiconductor light emitting element 3 can be reflected using a solid material surface such as ceramic or resin. In this case, since the light is irregularly reflected, a uniform diffuse reflection surface can be formed. On the other hand, in order to obtain a light condensing effect, a regular reflection surface made of gold (Au), silver (Ag), or a Bragg mirror using a dielectric multilayer film is formed on the side surface of the recess 1a. That's fine.

  When a plurality of land electrodes 5a, 5b, and 5c are provided as in the light emitting device shown in FIGS. 5A and 5B, the land electrodes 5a, 5b, and 5c are electrolytically plated. Therefore, it is necessary to connect the electric wirings 25a, 25b, 25c for plating to the respective land electrodes 5a, 5b, 5c. In the light emitting device shown in FIG. 5A, the electrical wirings 25 a, 25 b, and 25 c are provided only on the upper side of the package 1. On the other hand, in the light emitting device shown in FIG. 5B, the electrical wirings 25 a, 25 b, and 25 c are provided only on the lower side of the package 1.

  Therefore, in the light emitting device illustrated in FIG. 5A, it is possible to prevent a short circuit when the mounting circuit board is disposed on the lower side of the light emitting device. On the other hand, in the light emitting device shown in FIG. 5B, it is possible to prevent a short circuit when the mounting circuit board is arranged on the upper side of the light emitting device.

  Further, a gap D exists between the upper ends of the land electrodes 5a, 5b and 5c and the lead electrodes 5d and 5e and the upper surface 1c, and the lower ends of the land electrodes 5a, 5b and 5c and the lead electrodes 5d and 5e. A gap E exists between the portion and the mounting mount surface 1m. Accordingly, in the light emitting device shown in FIGS. 5A and 5B, the land electrodes 5a, 5b, and 5c (electrical wirings 25a, 25b, and 25c) and the lead electrodes 5d and 5e are mounted on the mounting mount surface electrode 2a ( Except for the power supply electrode surface), it is not exposed to the mounting mount surface 1m.

  Therefore, the light emitting device shown in FIG. 5A has a structure that can more reliably prevent a short circuit when the mounting circuit board is disposed on the lower side of the light emitting device. On the other hand, the light emitting device shown in FIG. 59B has a structure that can more reliably prevent a short circuit when the mounting circuit board is disposed on the upper side of the light emitting device.

  The light emitting device shown in FIG. 1A has a structure in which the wall thickness B between the recess 1a and the mounting mount surface 1m is thinner than the wall thickness A between the recess 1a and the upper surface 1c. Have. In contrast, in the light emitting device shown in FIG. 1B, the wall thickness B between the recess 1a and the mounting mount surface 1m is larger than the wall thickness A between the recess 1a and the upper surface 1c. The one has a thicker structure.

  If the thickness of the wall (reflection surface) of the package 1 on the circuit board mounting side is thin, the light emitted from the semiconductor light emitting element is transmitted through the reflection surface, so that the luminance of the light emitted in front of the light emitting device is lowered. To do. On the other hand, many white resist materials for mounting circuit boards have high reflectivity, and it is possible to plate a metal having high reflectivity on the mounting circuit board. Therefore, even if the thickness of the wall (reflective surface) of the package 1 on the circuit board mounting side is reduced, it is reflected on the mounting circuit board and sufficient reflectance can be secured.

  For this reason, the light emitting device shown in FIG. 1A has a structure in which the thickness B of the wall (reflective surface) between the recess 1a and the mounting mount surface 1m is thin. By providing a reflective material having a reflectance, a sufficient reflectance can be secured even on the wall (reflective surface) between the recess 1a and the mounting mount surface 1m. On the other hand, since the thickness A is thicker than the thickness B on the wall (reflective surface) between the recess 1a and the upper surface 1c, a sufficient reflectance can be ensured.

  The light emitting device shown in FIG. 1B has a structure in which the thickness B of the wall (reflection surface) between the recess 1a and the mounting mount surface 1m is thick. When the reflectance cannot be improved on the mounting circuit board side, or when it is not easy to improve, or when there are structural restrictions on the light emitting unit described later, the wall (reflecting surface) of the package 1 is thick. In some cases, the mounting surface is 1 m. In such a case, the reflectance on the mounting circuit board side can be secured by increasing the thickness B of the wall (reflection surface) between the recess 1a and the mounting mount surface 1m. On the other hand, on the wall (reflective surface) between the recess 1a and the upper surface 1c, a resist material having a high reflectivity or a metal having a high reflectivity may be contacted to reflect light.

  As described above, according to the present embodiment, the thickness of the upper or lower reflecting surface is reduced, and the reflecting material is provided on the upper side or the lower side, thereby ensuring the thinning of the light emitting device. Light can be efficiently emitted in front of the light emitting device.

Hereinafter, a method for manufacturing the light emitting device according to the present embodiment will be described.
FIG. 6 is a flowchart illustrating the method for manufacturing the light emitting device according to this embodiment.
FIG. 7 is a schematic view illustrating a step of cutting out each light emitting device from a base on which the package of the light emitting device according to this embodiment is continuously formed.

  The light emitting device according to this embodiment can be formed by laminating ceramic green sheets. The package 1 has a green sheet for forming the substrate 20 and a green sheet constituting the frame body 21. Each of the substrate 20 and the frame body 21 may be composed of a plurality of green sheets.

  Patterning of the land electrodes 5a, 5b, 5c and the lead electrodes 5d, 5e is formed on the upper surface of the green sheet for forming the substrate 20, and the rear electrode 2d, the heat radiation member 9, etc. are formed on the rear surface of the green sheet. The pattern is formed (step S102). On the other hand, the pattern of the light emitting surface electrode 2b is also formed on the green sheet for forming the frame body 21 (step S104).

  Thereafter, the green sheet forming the substrate 20 and the rear surface of the green sheet forming the frame 21 are overlapped to form the through hole 6 (step S106), and the metallized paste is embedded therein (step S108). Thereafter, the stacked ceramic green sheets are fired at a high temperature to form a ceramic sintered body (step S110), and further, the metal surface formed by the metallized paste is plated to form the package 1 (step S112).

  Thereafter, the semiconductor light emitting device 3 is mounted on the land electrodes 5a, 5b, 5c (step S114). Then, the bonding wires 4 connect the electrodes provided in the semiconductor light emitting element 3 to the land electrodes 5b and 5c and the lead electrode 5e, and between the land electrode 5a and the lead electrode 5d ( Step S116). Thereafter, the recess 1a is filled by potting to form the resin 16 (step S118). Thereafter, the substrate is cut by the dicing blade 200 along the dicing lines 50 and 52 to cut out the light emitting device (step S120).

FIG. 8 is a schematic view of a step of cutting out each light emitting device from a base on which the package of the light emitting device according to this embodiment is continuously formed, as viewed from the front side.
In order to electrolytically plate the land electrodes 5a, 5b, and 5c, electric wirings 25a, 25b, and 25c corresponding to the land electrodes 5a, 5b, and 5c are provided on the upper side of the package.

  The plating electric wires 25a, 25b, and 25c are connected to a plating wire 25 provided on the upper side. In the case where the land electrodes 5a, 5b, and 5c are plated by the electrolytic plating method, by applying a voltage to the plated wire 25, the electric wirings 25a, 25b for plating connected to the land electrodes 5a, 5b, and 5c, respectively. , 25c, a voltage is applied to the land electrodes 5a, 5b, 5c, and electrolytic plating is performed.

  After the electrolytic plating process is completed, the substrate is cut by a dicing blade along the dicing line 50 to cut out individual light emitting devices. In this dicing process, the plated wire 25 provided on the upper side of the package is also scraped off at the same time. As a result, the ends of the electric wirings 25a, 25b, 25c for plating connected to the land electrodes 5a, 5b, 5c are exposed at the upper end of the package. When the electrical wiring 25a, 25b, 25c is exposed at the upper end portion of the package, when the mounting circuit board is disposed on the upper side of the package, the ends of the electrical wirings 25a, 25b, 25c touch the other electrodes such as the mounting circuit board. There is a possibility of short-circuiting. Therefore, when the electrical wirings 25a, 25b, and 25c are provided only on the side opposite to the side on which the mounting circuit board is provided, it is possible to prevent the electrical wirings 25a, 25b, and 25c from touching other electrodes such as the mounting circuit board and short-circuiting. .

  As described above, according to the manufacturing method of the light emitting device according to the present embodiment, the side view type light emission is achieved by stacking the green sheets on which the metallized pattern is formed, forming the through holes, and metallizing the inside thereof. The device can be manufactured. Further, in the dicing process, the land electrodes 5a, 5b, and 5c can be made independent as respective electric wirings.

Hereinafter, modifications of the present embodiment will be described with reference to the drawings.
FIG. 9 is a schematic view illustrating a light emitting device according to a modified example of the embodiment.
The light emitting device according to this modification has a structure without a wall (reflection surface) between the recess 1a and the mounting mount surface 1m. In other words, the thickness B of the wall (reflection surface) between the recess 1a and the mounting mount surface 1m in the light emitting device shown in FIGS. 1 to 4 is zero. In this respect, the light emitting device shown in FIGS. 1 to 4 is different from the light emitting device shown in FIG. Other structures, materials, manufacturing methods, and the like are the same as those of the light-emitting device illustrated in FIGS.

  In the light emitting device shown in FIG. 9, since there is no lower reflective surface, the light emitted from the semiconductor light emitting element 3 is transmitted downward and the luminance of the light emitted in front of the light emitting device is reduced. There is. On the other hand, by providing a reflective material having a high reflectance on the mounting circuit board, sufficient reflectance can be secured even at the lower end of the light emitting device. On the other hand, since the thickness A is thick on the wall (reflection surface) between the recess 1a and the upper surface 1c, a sufficient reflectance can be ensured.

  As described above, according to the modification of the present embodiment, further reduction in thickness of the light-emitting device is ensured by eliminating the lower reflective surface and providing a reflective material having a high reflectance on the mounting circuit board. However, light can be efficiently emitted in front of the light emitting device.

Next, a second embodiment of the present invention will be described.
FIG. 10 is a schematic view illustrating a light emitting device according to the second embodiment of the invention.
The state of the internal wiring of the light emitting device according to this embodiment is as in the light emitting device shown in FIG. Similar to the light emitting device shown in FIG. 3, the structure other than the state of the internal wiring has a substantially rectangular parallelepiped package 1 provided with a recess 1a and a semiconductor light emitting element 3 provided in the recess 1a. . On the bottom surface of the recess 1a, land electrodes 5a, 5b, 5c, which are bottom electrodes, and lead electrodes 5d, 5e are provided. The semiconductor light emitting element 3 is mounted on the land electrodes 5a, 5b, and 5c. An electrode (not shown) provided in the semiconductor light emitting element 3 is connected to the land electrodes 5 b and 5 c and the lead electrode 5 e by bonding wires 4. Similarly, the land electrode 5a and the lead electrode 5d are connected by the bonding wire 4. And the recessed part 1a is sealed with translucent resin 16 (refer FIG. 4), such as an epoxy and silicone.

  The land electrodes 5a, 5b, and 5c and the lead electrodes 5d and 5e are provided inside the package 1 while being insulated from each other. The lead electrodes 5 d and 5 e extend to the left and right ends of the package 1 and are connected to a mounting mount surface electrode 2 a provided on the outer surface of the package 1. That is, the mounting mount surface electrodes 2a at the left and right ends of the package 1 are connected to the land electrodes 5a, 5b, 5c and the electrodes of the semiconductor light emitting element 3 through the lead electrodes 5d, 5e and the bonding wires 4. Yes.

  The recess 1 a is provided on the front surface 1 b corresponding to the light emitting surface of the package 1. On the side surface substantially orthogonal to the front surface 1b, a pair of mounting mount surface electrodes 2a (feeding electrode surfaces) are provided at the left and right ends, and a mounting mount surface 1m is provided between the mounting mount surface electrodes 2a. At the left and right ends of the front surface 1b corresponding to the light emitting surface of the package 1, light emitting surface electrodes 2b are provided. At the left and right ends of the upper surface 1c of the package 1, upper surface electrodes 2c are provided, and at the left and right ends of the rear surface 1d of the package 1, rear electrodes 2d (see FIG. 2) are provided.

On the other hand, the light emitting device shown in FIG. 10 has a wall thickness (reflective surface) A between the recess 1a and the upper surface 1c and a wall (reflective surface) between the recess 1a and the mounting mount surface 1m. The thickness B is substantially the same. In this respect, the light emitting device shown in FIG. 3 is different from the light emitting device shown in FIG.
In the light emitting device of this embodiment, as described above with reference to FIG. 5A, the land electrodes 5a, 5b, and 5c (electrical wirings 25a, 25b, and 25c) are not exposed on the mounting mount surface 1m. Therefore, when the light emitting device is mounted on a mounting circuit board or the like, a short circuit caused by the land electrodes 5a, 5b, 5c (electrical wirings 25a, 25b, 25c) coming into contact with other electrodes of the mounting circuit board can be prevented. . In the specific example shown in FIG. 5B as well, since the electrical wirings 25a, 25b, and 25c are not exposed on the mounting mount surface 1m, a short circuit occurs when mounted on a mounting circuit board or the like. There is no.

Hereinafter, modifications of the present embodiment will be described with reference to the drawings.
FIG. 11 is a schematic view illustrating a light emitting device according to a modification of the present embodiment, and FIG. 11A is a schematic view illustrating a light emitting device having no lower reflecting surface, and FIG. ) Is a schematic view illustrating a light emitting device having no upper reflecting surface.

  The state of the internal wiring of the light emitting device shown in FIG. 11A is the same as the state of the internal wiring of the light emitting device shown in FIG. 5A, and the electrical wirings 25 a, 25 b, 25 c are only on the upper side of the package 1. Is provided. In contrast, the state of the internal wiring of the light emitting device shown in FIG. 11B is similar to the state of the internal wiring of the light emitting device shown in FIG. 1 is provided only on the lower side.

  In the light emitting device shown in FIG. 11A, a gap E exists between the lower ends of the land electrodes 5a, 5b, 5c and the lead electrodes 5d, 5e and the mounting mount surface 1m, and FIG. In the light emitting device shown in FIG. 4A, there is a gap D between the upper ends of the land electrodes 5a, 5b, and 5c and the lead electrodes 5d and 5e and the upper surface 1c. Further, a reflecting material 27 is provided at the lower end portion of the light emitting device shown in FIG. 11A, and a reflecting material 27 is provided at the upper end portion of the light emitting device shown in FIG. Yes. Other structures, materials, manufacturing methods, and the like are the same as those of the light-emitting device described in the first embodiment.

  Accordingly, the light-emitting device illustrated in FIG. 11A has a structure that can more reliably prevent a short circuit when the mounting circuit board is disposed below the light-emitting device. In addition, the light emitting device illustrated in FIG. 11B has a structure that can more reliably prevent a short circuit when the mounting circuit board is disposed on the upper side of the light emitting device.

  In the light emitting device shown in FIG. 11A, since there is no lower reflective surface, the light emitted from the semiconductor light emitting element 3 is transmitted downward, and the luminance of the light emitted in front of the light emitting device is high. In some cases, the reflective material 27 is provided at the lower end, but sufficient reflectance can be ensured even on the lower side of the light emitting device. On the other hand, since the thickness A is thick on the wall (reflection surface) between the recess 1a and the upper surface 1c, a sufficient reflectance can be ensured.

  On the other hand, in the light emitting device shown in FIG. 11B, since there is no upper reflecting surface, the light emitted from the semiconductor light emitting element 3 is transmitted upward and is emitted to the front of the light emitting device. Although the brightness of the light is reduced, a sufficient reflectance can be ensured even on the upper side of the light emitting device by providing the reflector 27 at the upper end. On the other hand, since the thickness B is thick on the wall (reflection surface) between the recess 1a and the upper surface 1c, a sufficient reflectance can be ensured.

  FIG. 12 is a schematic view illustrating a light emitting device according to another modified example of the present embodiment. FIG. 12A shows a light emitting device that has no reflective surfaces on both upper and lower sides and is provided with a reflective material at the lower end. FIG. 12B is a schematic view illustrating a light emitting device that has no upper and lower reflecting surfaces and is provided with a reflective material at the upper end.

  In the light emitting device shown in FIG. 12A, a gap E exists between the lower ends of the land electrodes 5a, 5b and 5c and the lead electrodes 5d and 5e and the mounting mount surface 1m. In the light emitting device shown in (b), a gap D exists between the ends of the land electrodes 5a, 5b, 5c and the lead electrodes 5d, 5e and the mount mounting surface 1m. Further, a reflective material 27 is provided at the lower end portion of the light emitting device shown in FIG. 12A, and the reflective material 27 is provided on the side of the mount mounting surface 1m of the light emitting device shown in FIG. Is provided. Further, the light emitting device shown in FIG. 12A has no upper reflecting surface, and the light emitting device shown in FIG. 12B has no lower reflecting surface. Other structures, materials, manufacturing methods, and the like are the same as those of the light-emitting device described in the first embodiment.

  Accordingly, the light-emitting device shown in FIG. 12A has a structure that can more reliably prevent a short circuit when the mounting circuit board is disposed below the light-emitting device. On the other hand, the light emitting device shown in FIG. 12B has a structure that can more reliably prevent a short circuit when the mounting circuit board is disposed on the upper side of the light emitting device.

  In the light emitting device shown in FIG. 12A, since there is no lower reflecting surface, the light emitted from the semiconductor light emitting element 3 is transmitted downward and the luminance of the light emitted forward of the light emitting device is high. Although it is reduced, a sufficient reflectance can be secured even on the lower side of the light emitting device by providing the reflecting material 27 at the lower end. On the other hand, since there is no upper reflecting surface, the light emitted from the semiconductor light emitting element 3 is transmitted upward, and the luminance of the light emitted in front of the light emitting device is lowered. By providing, sufficient reflectance can be ensured.

  On the other hand, in the light emitting device shown in FIG. 12B, since there is no upper reflecting surface, the light emitted from the semiconductor light emitting element 3 is transmitted upward and emitted to the front of the light emitting device. Although the brightness of the light is reduced, a sufficient reflectance can be ensured even on the upper side of the light emitting device by providing the reflector 27 at the upper end. On the other hand, since there is no reflecting surface on the lower side, the light emitted from the semiconductor light emitting element 3 is transmitted downward and the luminance of the light emitted in front of the light emitting device is lowered. By providing, sufficient reflectance can be ensured.

As described above, according to the present embodiment, since the electrical wirings 25a, 25b, and 25c are exposed only on the upper side or the lower side of the package 1, the mounting circuit board is placed on the lower side or the upper side of the light emitting device. In the case of being arranged, it is possible to prevent a short circuit.
Further, by eliminating the reflecting surfaces on the lower side, the upper side, or both the upper and lower sides and providing the reflecting material, it is possible to efficiently emit light in front of the light emitting device while ensuring the thinning of the light emitting device.

Next, a third embodiment of the present invention will be described.
FIG. 13 is a schematic view illustrating a light emitting unit according to the third embodiment of the invention. The light emitting unit according to the present embodiment can be used as, for example, a planar light emitting device. The light emitting device shown in FIG. 13 is similar to the light emitting device shown in FIG. 1A in that the wall thickness between the recess and the mounting mount surface is greater than the wall thickness A between the recess and the upper surface. B has a thinner structure. A reflective material 37 is provided on the upper side of the package 1. However, since the thickness A of the wall between the concave portion and the upper surface is thick, the reflecting material 37 may not be provided.

  In the planar light emitting device, a mounting circuit board 31a coated with a reflective material, a back frame 33a, a side frame 33b, a front frame 33c, and a light guide plate 36 are provided. The light guide plate 36 is provided on the front side of the light emitting device. Further, a lens sheet 34 and a diffusion sheet 35 are provided above the light guide plate 36, and a reflection sheet 32 is provided between the light guide plate 36 and the back frame 33 a.

  Since the light emitting device shown in FIG. 13 has a structure in which the wall thickness B between the recess and the mounting mount surface is thin, the light emitted from the semiconductor light emitting element 3 is transmitted through the lower reflective surface. It's easy to do. For this reason, the luminance of the light emitted to the light guide plate 36 provided in front of the light emitting device may be lowered. However, since the reflective material having a high reflectance is applied to the mounting circuit board 31a, this reflective material is used. Can be emitted to the light guide plate 36. Therefore, even if the wall thickness B between the recess and the mounting mount surface is reduced, sufficient reflectance can be ensured.

  On the other hand, since the thickness of the wall between the recess and the upper surface is thick, a sufficient reflectance can be ensured. Further, since the reflecting material 37 is provided on the upper side of the package 1, light can be emitted forward more efficiently. The reflective material 37 may be made of a material having high thermal conductivity. According to this, the reflective material 37 can have the function of the member 9 for heat dissipation, and is formed integrally.

The reflective material 37 having high thermal conductivity is a mixture of a light reflective material such as titanium oxide or magnesium oxide and a material having high heat dissipation properties such as silica (SiO ₂ ), BN, SiC, or diamond. Made of silicone resin. Further, if a conductive resin material mixed with carbon or metal is used, a reflective material 37 with higher heat dissipation can be realized.

  In the light emitting unit of the present embodiment, an insulating resin is applied in advance to the mounting mount surface electrodes 2a (feeding electrode surfaces) provided at the left and right ends of the light emitting device and dried, and then a conductive resin is applied. What is necessary is just to dry. In this case, it is important to eliminate the electric wiring on the side in contact with the conductive resin as in the light emitting device shown in FIG. In the case of applying the resin, a commonly used dispenser or the like can be used, and improvement in thermal conductivity and light reflectance can be realized by a simple process.

Hereinafter, modifications of the present embodiment will be described with reference to the drawings.
FIG. 14 is a schematic view illustrating a light emitting unit according to a modification of this embodiment.
The light-emitting device according to the present modification includes substantially rectangular land electrodes 5a, 5b, and 5c each provided with a recess 1a, and a semiconductor light-emitting element 3 provided in the recess 1a. Lead electrodes 5d and 5e are provided at the left and right ends, respectively. The semiconductor light emitting element 3 is mounted on the land electrodes 5a, 5b, and 5c. An electrode (not shown) provided in the semiconductor light emitting element 3 is connected to the land electrodes 5 b and 5 c and the lead electrode 5 e by bonding wires 4. Similarly, the land electrode 5a and the lead electrode 5d are connected by the bonding wire 4.

  The land electrodes 5a, 5b, 5c, the lead electrodes 5d, 5e, the semiconductor light emitting element 3, and the bonding wire 4 are sealed with a light-transmitting resin 16 such as epoxy or silicone as a whole. The land electrodes 5a, 5b, and 5c and the lead electrodes 5d and 5e are made of a metal material.

  The light emitting device shown in FIG. 14 has a structure in which the wall thickness between the recess and the mounting mount surface and the wall thickness between the recess and the upper surface are thin. The emitted light is likely to pass through the lower and upper reflecting surfaces. Therefore, there is a possibility that the luminance of the light emitted in front of the light emitting device may decrease, but since the reflective material having a high reflectance is applied to the mounting circuit board 31a, the light reflected by the reflective material is forwarded. Can radiate. Furthermore, since the reflecting material 37 is provided on the upper side of the light emitting device, the light reflected by the reflecting material can be emitted forward. The reflective material 37 may be a reflective material having high thermal conductivity, similar to the reflective material in the light emitting device shown in FIG.

  As described above, according to the present embodiment, the reflective circuit is applied to the mounting circuit board, or the reflective material is provided on the upper side or the rear side of the light emitting device, thereby ensuring the thinning of the light emitting device. The light can be efficiently emitted in front of the light emitting device.

The embodiment of the present invention has been described above. However, the present invention is not limited to these descriptions. As long as the features of the present invention are provided, those skilled in the art appropriately modified the design of the above-described embodiments are also included in the scope of the present invention. For example, the reflective material 37 in the light emitting device illustrated in FIG. 14 may be a reflective material having high thermal conductivity, similar to the reflective material 37 in the light emitting device illustrated in FIG.
Moreover, each element with which each embodiment mentioned above is provided can be combined as long as technically possible, and the combination of these is also included in the scope of the present invention as long as it includes the features of the present invention.

1 is a perspective view illustrating a light emitting device according to a first embodiment of the present invention, and FIG. 1A is a perspective view illustrating a light emitting device having a thick wall between a recess and an upper surface; (B) is the perspective view which illustrated the light-emitting device with a thin wall between a recessed part and an upper surface. It is the perspective view which looked at the light-emitting device concerning this embodiment from the back side. It is the front view which looked at the light-emitting device represented to Fig.1 (a) from the front side. 4A and 4B are schematic cross-sectional views of the light-emitting device shown in FIG. 3, FIG. 4A is a schematic view showing the AA ′ cross-section, and FIG. 4B is a schematic view showing the BB ′ cross-section. FIG. FIG. 5A is a schematic diagram illustrating the state of the internal wiring of the light emitting device according to this embodiment, and FIG. 5A is a schematic diagram illustrating the state of the internal wiring of the light emitting device in which the internal wiring is provided only on the upper side. FIG. 5B is a schematic view illustrating the state of the internal wiring of the light emitting device in which the internal wiring is provided only on the lower side. 3 is a flowchart illustrating a method for manufacturing the light emitting device according to the embodiment. It is the schematic diagram which illustrated the process of cutting out each light-emitting device from the base | substrate with which the package of the light-emitting device concerning this embodiment was formed continuously. It is the schematic diagram which looked at the process of cutting out each light-emitting device from the base | substrate with which the package of the light-emitting device concerning this embodiment was formed continuously from the front side. It is the schematic diagram which illustrated the light-emitting device concerning the modification of this embodiment. It is the schematic diagram which illustrated the light-emitting device concerning the 2nd Embodiment of this invention. FIG. 11A is a schematic view illustrating a light emitting device according to a modification of the present embodiment, FIG. 11A is a schematic view illustrating a light emitting device having no lower reflective surface, and FIG. It is the schematic diagram which illustrated the light-emitting device without the reflective surface of the side. It is the schematic diagram which illustrated the light-emitting device concerning the other modification of this embodiment, Fig.12 (a) is the schematic diagram which illustrated the light-emitting device without a lower reflective surface, FIG.12 (b) is FIG. It is the schematic diagram which illustrated the light-emitting device without an upper reflective surface. It is the schematic diagram which illustrated the light emission unit concerning the 3rd Embodiment of this invention. It is the schematic diagram which illustrated the light emitting unit concerning the modification of this embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Package, 1a Recessed part, 1b Front surface, 1c Upper surface, 1d Rear surface, 1m Mounting surface, 2a Mounting surface electrode, 2b Light emitting surface electrode, 2c Upper surface electrode, 2d Rear surface electrode, 3 Semiconductor light emitting element, 4 Bonding wire, 5a Land electrode, 5b Land electrode, 5d Lead electrode, 5e Lead electrode, 6 Through hole, 9 Heat radiating member, 16 Resin, 20 Substrate, 21 Frame, 25 Plated wire, 25a Electrical wiring, 27 Reflector, 31a Mounting circuit board 31b mounting circuit board, 32 reflective sheet, 33a back frame, 33b side frame, 33c front frame, 34 lens sheet, 35 diffusion sheet, 36 light guide plate, 37 reflective material, 50 dicing line, 200 dicing blade

Claims (5)

A substantially rectangular light emitting surface having a recess, a back surface facing the light emitting surface, a first surface that is substantially orthogonal to the light emitting surface and the back surface, and is connected to the light emitting surface and the back surface through a long side. And a package having a second side surface facing the first side surface,
A light emitting device provided in the recess;
With
The first side surface includes first and second power supply electrode surfaces connected to the light emitting element, and a mounting mount surface provided between the first power supply electrode surface and the second power supply electrode surface. And having
A step is provided between the first power supply electrode surface and the mounting mount surface,
A step is provided between the second power supply electrode surface and the mounting mount surface,
The first and second power supply electrode surfaces recede from the mounting mount surface adjacent thereto,
A light emitting device, wherein a thickness of a second wall between the concave portion and the second side surface is different from a thickness of the first wall between the concave portion and the first side surface.   The light-emitting device according to claim 1, wherein at least one of the first and second walls is absent.   The light emitting device according to claim 1, wherein at least one of the first and second side surfaces is covered with a light reflecting material. A land electrode extending to the bottom surface of the recess and connected to the light emitting element;
The light emitting device according to claim 1, wherein an end portion of the land electrode is not exposed to the mounting mount surface. A mounting board;
The light emitting device according to any one of claims 1 to 4, which is mounted on the mounting substrate,
With
A light emitting unit, wherein at least one of the first and second side surfaces is covered with a light reflecting material.

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