JP2017120929A - Light emitting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a compact side light emission type light emitting device.SOLUTION: A light emitting device 100 includes a substrate 10 having a longitudinal direction parallel to an upper surface 10a and one end surface 10b thereof, and plural light source portions arranged in the longitudinal direction of the substrate 10. The light source portion includes an element mounting portion 15 disposed on the upper surface 10a of the substrate 10, a light emitting element 20 connected to an element mounting portion 15, a white covering member 30 which is provided on the substrate 10 in contact with the light emitting element 20 so as to cover the periphery of the light emitting element 20, and substantially flush with the one end surface 10b of the substrate 10, and constitutes a mounting face of the light emitting device 100, and a translucent member 40 which is provided on the light emitting element 20 and has a phosphor 45 excited by light from the light emitting element 20.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a light emitting device, and more particularly to a side light emitting type (also referred to as “side view type”) light emitting device.

  Conventionally, a light emitting diode (LED) is used as a backlight light source of a display panel of an electronic device. Particularly in recent years, with the progress of thinner electronic devices and larger screens, display panels and light guide plates are required to be thinner and larger screens, and light-emitting diodes are also required to be thinner and higher output. It is becoming.

  For example, in Patent Document 1, the bases of lead terminals are respectively connected to both sides of a reflective case having an opening at the front and having a flat bottom, and a notch for accommodating a terminal is formed at the lower part of the rear of the reflective case. The lead terminal is integrally provided, and the lead terminal has a connection auxiliary portion extending rearward along the terminal holding portion from the side portion of the reflection case, and a notch portion provided on the front side of the connection auxiliary portion. A surface-mounting type semiconductor light emitting device is described in which a connecting portion to be housed is provided.

  Further, for example, in Patent Document 2, a plurality of light emitting elements are disposed at predetermined intervals along the longitudinal direction of an elongated rectangular bar-like wiring board and die-bonded, and on both sides of each light emitting element, In addition, reflectors are disposed so as to be alternately positioned with the respective light emitting elements, and the opposing surfaces of the two reflectors are inclined so that the opening area becomes larger toward the emission direction of the respective light emitting elements. A linear light source device is described. In addition, it is described that a reflection member made of a reflection sheet or a vapor deposition film is provided in a region extending from both end faces in the longitudinal direction adjacent to the mounting surface of the wiring board to the tip of the opposing surface of each reflection plate.

JP 2006-253551 A JP 2004-235139 A JP 2007-158209 A

  However, the semiconductor light-emitting device described in Patent Document 1 requires a gap between the reflective case and the semiconductor light-emitting element because the semiconductor light-emitting element is mounted in a reflective case molded in advance. Further, in the molding of the reflective case, the thickness of the reflective case cannot be sufficiently reduced due to the fluidity of the resin. Also in the linear light source device described in Patent Document 2, the reflecting member made of the reflecting plate, the reflecting sheet, and the vapor deposition film is separately disposed apart from the light emitting element, and can be sufficiently downsized. Absent.

  Therefore, the present invention has been made in view of such circumstances, and an object thereof is to provide a small side-emitting type light emitting device.

  In order to solve the above problems, the present invention is a light emitting device including a base body whose longitudinal direction is parallel to the upper surface and one end face, and a plurality of light source units arranged in the longitudinal direction of the base body, The light source unit includes an element mounting part disposed on the upper surface of the base, a light emitting element connected to the element mounting part, a white coating provided on the base that is in contact with and covers the light emitting element A member that is substantially flush with one end surface of the substrate and that forms a mounting surface of the light-emitting device; and is provided on the light-emitting element and excited by light from the light-emitting element And a translucent member having a phosphor.

  According to the present invention, the distance between the light emitting element and the light reflector surrounding the light emitting element can be reduced by providing the white covering member so as to be in contact with and cover the light emitting element. Moreover, since the one end surface of the coating | coated member comprises the mounting surface of the light-emitting device, it can be functioned as a side light emission type light-emitting device. Therefore, a side-emitting light emitting device that can be sufficiently miniaturized can be provided.

1A is a schematic plan view of a light-emitting device according to an embodiment of the present invention, and FIG. 1B is a schematic cross-sectional view taken along line IB-IB in FIG. 1A. It is a schematic perspective view which shows the state in which the light-emitting device which concerns on one embodiment of this invention was mounted in the mounting member. It is a flowchart which shows an example of the flow of the manufacturing method of the light-emitting device which concerns on one embodiment of this invention. 4A is a schematic plan view of a composite substrate used in the light emitting device according to the embodiment of the present invention, and FIG. 4B is a schematic cross-sectional view taken along line IVB-IVB in FIG. 4A. 5A is a schematic plan view of a light emitting device according to an embodiment of the present invention, and FIG. 5B is a schematic cross-sectional view taken along line VB-VB in FIG. 5A. 6A is a schematic plan view of a light emitting device according to an embodiment of the present invention, FIG. 6B is a schematic side view of FIG. 6A, and FIG. 6C is a schematic cross-sectional view taken along the line VIC-VIC in FIG. 7A is a schematic plan view of a light-emitting device according to an embodiment of the present invention, FIG. 7B is a schematic cross-sectional view taken along line VIIB-VIIB in FIG. 7A, and FIG. 7C is a schematic cross-sectional view taken along line VIIC-VIIC in FIG. FIG. 8A is a schematic plan view of a light emitting device according to an embodiment of the present invention, FIG. 8B is a schematic side view of FIG. 8A, and FIG. 8C is a schematic cross-sectional view taken along line VIIIC-VIIIC of FIG.

  Hereinafter, embodiments of the invention will be described with reference to the drawings as appropriate. However, the light-emitting device described below is for embodying the technical idea of the present invention, and the present invention is not limited to the following unless otherwise specified. The contents described in one embodiment and example are applicable to other embodiments and examples. In addition, the size, positional relationship, and the like of members illustrated in each drawing may be exaggerated for clarity of explanation.

  In the following, the “x” direction shown in the figure may be referred to as the “lateral” direction, the “y” direction as the “vertical” direction, and the “z” direction as the “vertical” direction or the “thickness” direction. Note that the light emitting devices of the following embodiments and examples are those in which the horizontal direction is the longitudinal direction when viewed from above, but this is not restrictive.

<Embodiment 1>
1A is a schematic plan view showing the light-emitting device according to Embodiment 1, and FIG. 1B is a schematic cross-sectional view showing a cross section AA in FIG. 1A. As shown in FIGS. 1A to 1B, the light emitting device 100 according to Embodiment 1 includes a base 10, a light emitting element 20, a covering member 30, a translucent member 40, and a light shielding member 50. Yes.

  The base 10 includes an element mounting portion 15 on the upper surface 10a. More specifically, the base 10 is obtained by providing a pair of positive and negative electrodes 13 on a base material 11. The electrode 13 includes an element mounting portion 15, an external connection terminal portion 17, and a lead wiring portion 19. The element mounting part 15 is a part where the light emitting element 20 is mounted. The external connection terminal portion 17 is a portion connected to an external electrode by a conductive adhesive. The lead wiring part 19 is a part for connecting the element mounting part 15 and the external connection terminal part 17. The electrode 13 is provided continuously from the upper surface 10a of the substrate 10 to the lower surface 10c through the end surface. The lead-out wiring part 19 is preferably narrower than the external connection terminal part 17 or a part of the electrode is covered with a resist (not shown) so as to be visible. Thereby, it is possible to prevent the conductive adhesive connected to the external connection terminal portion 17 or the flux contained in the paste from entering under the covering member 30.

  The light emitting element 20 is flip-chip mounted (face-down mounted) on the element mounting portion 15 of the base. More specifically, the light-emitting element 20 includes a light-emitting element structure including a semiconductor laminate, a light-transmitting substrate connected to one main surface of the light-emitting element structure, and the other (opposite side) of the light-emitting element structure. And a pair of positive and negative electrodes connected to the main surface of the side. The pair of positive and negative electrodes of the light emitting element 20 are bonded to the element mounting portion 15 of the pair of positive and negative electrodes 13 of the base by a conductive adhesive 60 (first conductive adhesive), respectively.

  The covering member 30 is white, is in contact with the light emitting element 20 and covers the periphery thereof, and is provided on the substrate 10. More specifically, the covering member 30 is obtained by solidifying a resin containing the inorganic particles 35. Note that the periphery of the light emitting element 20 means the periphery (one round) of the light emitting element 20 in a top view of the light emitting element 20. That is, “the covering member 30 is in contact with and covers the light emitting element 20” means that the covering member 30 covers all the end surfaces 20 b (side surfaces) of the light emitting element 20 while leaving the upper surface 20 a of the light emitting element 20. It means to do. Further, as illustrated, the covering member 30 preferably covers the lower surface of the light emitting element 20 in order to efficiently extract light upward from the light emitting element 20. One end surface 30b of the covering member is substantially flush with the one end surface 10b of the base. And the one end surface 30b of a coating | coated member comprises the mounting surface of the said light-emitting device 100. FIG. Particularly in this example, the one end surface 30 b of the covering member is an end surface along the longitudinal direction of the light emitting device 100.

  The translucent member 40 is a translucent member provided on the light emitting element 20. More specifically, the translucent member 40 is provided in contact with the upper surface 20a of the light emitting element and the upper surface 30a of the covering member. The one end surface 40b of the translucent member is substantially flush with the one end surface 10b of the base and the one end surface 30b of the covering member. The translucent member 40 has a phosphor 45.

  A light shielding member 50 is provided on the translucent member 40. More specifically, the light shielding member 50 is provided in contact with the upper surface 40a of the translucent member. The one end surface of the light shielding member 50 is also substantially flush with the one end surface 10b of the substrate, the one end surface 30b of the covering member, and the one end surface 40b of the translucent member. The light shielding member 50 reflects or absorbs light to be emitted from the translucent member 40 and limits a light emitting region on the upper surface 40a of the translucent member. The light shielding member 50 has a frame shape with an opening at the center. Therefore, in the light emitting device 100, a region exposed from the light shielding member 50 in the upper surface 40a of the translucent member is a main light emitting region.

  FIG. 2 is a schematic perspective view showing a state where the light emitting device according to Embodiment 1 is mounted on a mounting member. As shown in FIG. 2, the light emitting device 100 is mounted on the mounting member 70 using a conductive adhesive 75 (second conductive adhesive). More specifically, the external connection terminal portions 17 of the positive electrode / negative electrode 13 of the light emitting device 100 are respectively bonded to the positive / negative device mounting portions 73 of the mounting member by the conductive adhesive 75. At this time, the one end surface 30 b of the covering member 30 is disposed so as to face the upper surface of the mounting member 70 together with the one end surface 10 b of the base 10. In this manner, the light emitting device 100 is mounted on the mounting member 70 with the upper surface thereof, that is, the upper surface 20a of the light emitting element (in addition, the upper surface 40a of the translucent member) facing sideways, and the side light emitting type. It functions as a light emitting device. In particular, the one end surface 30 b of the covering member 30 is preferably in contact with the upper surface of the mounting member 70 together with the one end surface 10 b of the base 10. Thereby, it is easy to efficiently conduct heat from the light emitting device 100 to the mounting member 70, and heat dissipation of the light emitting device 100 can be easily improved.

  The light emitting device 100 configured as described above can function as a side light emitting device. Further, the distance between the light emitting element and the light reflector surrounding the light emitting element can be reduced, and the device can be sufficiently downsized. Moreover, the light utilization efficiency can be increased by reflecting the light emitted from the light emitting element to the front (upward) by the white covering member and taking it out. Furthermore, the light emitting device can be reduced in size while maintaining the size of the light emitting element, and a high output light emitting device can be easily obtained. Furthermore, the heat generated from the light emitting element and the phosphor can be radiated through the covering member.

  FIG. 3 is a flowchart showing an example of the flow of the method for manufacturing the light emitting device according to the first embodiment. 4A is a schematic plan view of the composite substrate used in the light-emitting device according to Embodiment 1, and FIG. 4B is a schematic cross-sectional view showing a BB cross section in FIG. 4A. As shown in FIG. 3, the light emitting device 100 can be manufactured through a light emitting element mounting step, a covering member forming step, a translucent member forming step, a light shielding member forming step, and an individualization step. In addition, when not forming a translucent member and / or a light shielding member, a translucent member formation process and / or a light shielding member formation process shall be abbreviate | omitted.

  In the method for manufacturing the light emitting device 100, a composite substrate 80 in which a composite electrode 83 is formed on a base material 81 of the composite substrate as shown in FIGS. 4A to 4B is used. The composite substrate 80 is formed by connecting a plurality of substrates that become the substrate 10 of each light emitting device after the individualization step. That is, after the singulation process, the base material 81 of the composite base becomes the base material 11 of the base in each light emitting device, and the composite electrode 83 becomes the electrode 13 of the base in each light emitting device. Further, the composite substrate 80 has notches 87 formed on both sides of the composite electrode 83. The composite electrode 83 is provided continuously from the upper surface to the lower surface of the base material 81 of the composite substrate through the notch 87. 4A to 4B show the composite substrate 80 from which 18 light emitting devices are obtained for convenience of explanation, but in order to increase production efficiency, a larger number (hundreds to thousands) of light emitting devices are obtained. It is preferable to use a composite substrate.

  First, in the light emitting element mounting step, each light emitting element is flip-chip mounted on the element mounting portion of the composite electrode 83 of the composite substrate 80.

  Next, in the covering member forming step, the covering member is formed so as to be in contact with the mounted light emitting element and cover the periphery thereof. At this time, the covering member is provided so as to continuously cover the light emitting elements arranged in the vertical direction (see the covering member forming region 85 in FIGS. 4A to 4B). The covering member can be formed by screen printing or dripping (potting). Further, at this time, the covering member may be provided so as to once cover the upper surface of the light emitting element. In that case, the covering member on the upper surface of the light emitting element may be removed later by polishing or the like.

  Next, in the translucent member forming step, a translucent member is formed on the light emitting element. The translucent member can be formed by a hot-melt bonding method or an adhesive bonding. Further, if necessary, a light shielding member is formed on the translucent member in the light shielding member forming step. The light shielding member can be formed by a printing method or a pasting method, adhesion with an adhesive, or the like.

  Finally, in the singulation step, the composite base 80 and the covering member are cut in the horizontal direction along the planned dividing line L, and the light emitting device is singulated. Dicer, laser irradiation, or the like can be used for cutting. Here, as shown in FIGS. 4A to 4B, it is preferable that the light emitting device is already separated in the lateral direction by the notch 87 extending in the longitudinal direction because the light emitting device can be singulated with a relatively small number of man-hours. . In addition, when a translucent member is formed continuously similarly to the covering member, the translucent member is also divided at the same time. The same applies to the light shielding member.

  Hereinafter, other preferable modes according to the light emitting device of the present embodiment will be described.

  In the light emitting device 100 shown in FIGS. 1A to 1B, the one end faces 10b and 30b of the base and the covering member are long in a direction parallel to the one end faces 10b and 30b and the top face 10a of the base. Furthermore, the one end surfaces 10b and 30b of the base body and the covering member are shortened in the vertical direction. In other words, in the light emitting device 100, the one end surfaces 10b and 30b of the base body and the covering member are long in the lateral direction (x direction in the figure) and short in the thickness direction (z direction in the figure). Thereby, it is easy to form the light emitting device 100 thin. Moreover, it is easy to increase the contact area between the end faces 10b and 30b of the substrate and the covering member and the mounting member, and it is easy to improve the heat dissipation of the light emitting device 100.

  In the light emitting device 100 shown in FIG. 1A to FIG. 1B, a translucent member 40 having a phosphor 45 excited by light from the light emitting element 20 is provided on the light emitting element 20. The one end surface 40b constitutes a mounting surface of the light emitting device 100. Thereby, the heat generated from the phosphor 45 in the translucent member 40 can be easily conducted to the mounting member, and the heat dissipation of the light emitting device 100 can be easily improved. In particular, the one end surface 40 b of the translucent member is preferably in contact with the upper surface of the mounting member 70. Thereby, it is easy to efficiently conduct heat from the light emitting device 100 to the mounting member 70, and heat dissipation of the light emitting device 100 can be easily improved.

  In the light emitting device 100 shown in FIGS. 1A to 1B, the covering member 30 contains inorganic particles 35. Thereby, the heat generated from the light emitting element 20 and the phosphor 45 can be easily conducted to the mounting member via the covering member 30, and the heat dissipation of the light emitting device 100 can be easily improved.

  In the light emitting device 100 shown in FIGS. 1A to 1B, the base 10 includes an external connection terminal portion 17 that is electrically connected to the element mounting portion 15, and the external connection terminal portion 17 is provided on the upper surface 10 a of the base. . In this way, by attaching the external connection terminal portion 17 provided on the upper surface 10a of the base body to the device mounting portion of the mounting member with a conductive adhesive, the one end surface 30b of the covering member is easily brought into contact with the upper surface of the mounting member. Therefore, the heat dissipation of the light emitting device 100 can be easily improved.

  In the light emitting device 100 shown in FIGS. 1A to 1B, the external connection terminal portion 17 is also provided on the lower surface 10c of the base. In this way, in addition to the external connection terminal portion 17 provided on the upper surface 10a of the base, the external connection terminal portion 17 provided on the lower surface 10c of the base is also bonded to the device mounting portion of the mounting member with a conductive adhesive. Therefore, it is easy to improve the heat dissipation of the light emitting device 100 by suppressing the floating of the light emitting device 100 from the mounting member. Further, the mounting stability of the light emitting device 100 can be improved.

<Embodiment 2>
5A is a schematic plan view showing the light-emitting device according to Embodiment 2, and FIG. 5B is a schematic cross-sectional view showing a VB-VB cross section in FIG. 5A. As shown in FIGS. 5A to 5B, the light emitting device 200 according to Embodiment 2 includes a base 10, a light emitting element 20, a covering member 30, a translucent member 40, and a light shielding member 50. Yes. More specifically, the base body 10 is provided with a plurality of element mounting portions 15 and light emitting elements 20 spaced apart from each other in the longitudinal direction, the direction parallel to the upper surface 10a and the one end face 10b of the base body being the longitudinal direction. The covering member 30 covers the periphery of each light emitting element 20. The light emitting device 200 has a configuration in which a plurality of light emitting devices 100 according to Embodiment 1 are connected in the horizontal direction. Therefore, the description of the same configuration as the light emitting device 100 of the light emitting device 200 is omitted.

  The light-emitting device 200 includes a negative electrode (composite electrode) for one light-emitting device and a positive-electrode (composite electrode) for the adjacent light-emitting device without providing the notch 87 in the above-described composite substrate 80. ), And a plurality of light source portions each including the light emitting element 20, the covering member 30, the light transmissive member 40, and the light shielding member 50 are formed on the composite substrate in the lateral direction. It can be manufactured by cutting the composite substrate in the lateral direction so as to include the light source part.

  Such a light emitting device 200 can be used as a linear side light emitting device. In addition, the light emitting device 200 can easily improve the mounting position accuracy of the light source unit as compared with, for example, the conventional side surface light emitting device as described in Patent Document 1 is individually mounted on the mounting member. Furthermore, the light emitting device 200 can improve alignment with the light guide plate as a backlight light source.

  In the light emitting device 200, the external connection terminal portions 17 provided at both ends in the horizontal direction are bonded to the electrodes of the mounting member with a conductive adhesive, and can be made to emit light by supplying power. Moreover, as shown to FIG. 5A-FIG. 5B, the heat dissipation of a light-emitting device can be improved by utilizing the lead-out wiring part 19 which connects between adjacent light source parts as an auxiliary electrode. Further, as in this example, an auxiliary electrode may be formed on the lower surface side of the substrate 10 through a through hole or the like.

<Embodiment 3>
6A and 6B are a schematic plan view and a schematic side view showing the light emitting device according to Embodiment 3, respectively. FIG. 6C is a schematic cross sectional view showing a VIC-VIC cross section in FIG. 6A. As shown in FIGS. 6A to 6C, the light emitting device 300 according to Embodiment 3 includes a base 10, a light emitting element 20, a covering member 30, and a translucent member 40.

  The base 10 includes an element mounting portion 15 on the upper surface 10a. More specifically, the base 10 is obtained by providing a pair of positive and negative electrodes 13 on a base material 11. The electrode 13 includes an element mounting portion 15, an external connection terminal portion 17, and a lead wiring portion 19. The element mounting part 15 is a part where the light emitting element 20 is mounted. The external connection terminal portion 17 is a part connected to an external electrode. The lead wiring part 19 is a part for connecting the element mounting part 15 and the external connection terminal part 17. The electrode 13 is provided continuously from the upper surface 10a of the substrate 10 to the end surface. The lead-out wiring part 19 is preferably narrower than the external connection terminal part 17 or a part of the electrode is covered with a resist (not shown) so as to be visible. Thereby, it is possible to prevent the conductive adhesive connected to the external connection terminal portion 17 or the flux contained in the paste from entering under the covering member 30.

  The light emitting element 20 is flip-chip mounted (face-down mounted) on the element mounting portion 15 of the base. More specifically, the light-emitting element 20 includes a light-emitting element structure including a semiconductor laminate, a light-transmitting substrate connected to one main surface of the light-emitting element structure, and the other (opposite side) of the light-emitting element structure. And a pair of positive and negative electrodes connected to the main surface of the side. The pair of positive and negative electrodes of the light emitting element 20 are bonded to the element mounting portion 15 of the pair of positive and negative electrodes 13 of the base by a conductive adhesive 60. Further, the light emitting element 20 is arranged on the upper surface 10a of the base body 10 so as to be offset toward the one end face 10b side of the base body.

  The covering member 30 is white, is in contact with the light emitting element 20 and covers the periphery thereof, and is provided on the substrate 10. The covering member 30 is in contact with the translucent member 40 and covers the periphery thereof. The covering member 30 is obtained by solidifying a resin containing the inorganic particles 35. Note that the periphery of the light emitting element 20 means the periphery (one round) of the light emitting element 20 in a top view of the light emitting element 20. That is, “the covering member 30 is in contact with and covers the light emitting element 20” means that the covering member 30 covers all the end surfaces 20 b (side surfaces) of the light emitting element 20 while leaving the upper surface 20 a of the light emitting element 20. It means to do. The same applies to the translucent member 40. Further, the upper surface 30a of the covering member is inclined or curved downward from the upper surface 40a of the translucent member. As illustrated, the covering member 30 preferably covers the lower surface of the light emitting element 20 in order to efficiently extract light upward from the light emitting element 20. One end surface 30b of the covering member is substantially flush with the one end surface 10b of the base. And the one end surface 30b of a coating | coated member comprises the mounting surface of the said light-emitting device 300. FIG. In particular, in this example, the one end surface 30 b of the covering member is an end surface along the longitudinal direction of the light emitting device 300.

  The translucent member 40 is a translucent member provided on the light emitting element 20. More specifically, the translucent member 40 is provided in contact with the upper surface 20a of the light emitting element. The top view shape of the translucent member 40 is substantially the same as that of the light emitting element. An upper surface 40 a of the translucent member 40 is exposed to the outside and constitutes a main light extraction surface of the light emitting device 300. The translucent member 40 has a phosphor 45.

  The light-emitting device 300 configured as described above can also function as a side-emitting light-emitting device. In addition, the distance between the light emitting element and the light reflector surrounding the light emitting element can be reduced, and the light emitting device can be sufficiently downsized. Moreover, the light utilization efficiency can be increased by reflecting the light emitted from the light emitting element to the front (upward) by the white covering member and taking it out. Furthermore, the light emitting device can be reduced in size while maintaining the size of the light emitting element, and a high output light emitting device can be easily obtained. Furthermore, the heat generated from the light emitting element and the phosphor can be radiated through the covering member.

  In the light emitting device 300 shown in FIGS. 6A to 6C, the thickness of the portion sandwiching the light emitting element 20 in the direction perpendicular to the one end surface 30 b of the covering member 30 is smaller on the one end surface 30 b side than the opposite side. Accordingly, the distance between the light emitting element 20 and the mounting member can be easily reduced, and heat generated from the light emitting element 20 can be easily conducted to the mounting member, so that the heat dissipation of the light emitting device 300 can be easily improved. In addition, since the light emitting region of the light emitting device can be provided at a relatively low position, it is easy to efficiently make light incident on a relatively thin light guide plate.

  The light emitting device 300 illustrated in FIGS. 6A to 6C includes a protection element 90. This protective element 90 has electrodes on the upper and lower surfaces thereof, the lower electrode is connected to one electrode 13 of the base with a conductive adhesive, and the upper electrode is connected to the other electrode 13 of the base with a wire. Has been. The protective element 90 is buried in the covering member 30. Thereby, it is possible to suppress the light from the light emitting element 20 and the phosphor 45 from being absorbed by the protection element 90. Moreover, it is easy to select the installation location of the protection element 90 thereby. In particular, in this example, the protective element 90 is buried in the thicker part of the two parts sandwiching the light emitting element 20 in the direction perpendicular to the one end face 30b of the covering member 30, that is, the part opposite to the one end face 30b. ing.

  In the light-emitting device 300 illustrated in FIGS. 6A to 6C, the light-transmitting member 40 including the phosphor 45 that is excited by the light from the light-emitting element 20 is provided on the light-emitting element 20. The periphery of the translucent member 40 is covered. Thereby, it can suppress that light leaks from the translucent member 40 to the side. In addition, the luminous intensity forward to the light emitting device 300 is increased, and light can be efficiently incident on the light guide plate. Furthermore, color mixing of the light emitted from the light emitting element 20 and the wavelength converted light emitted from the phosphor 45 is promoted, and light emission with less color unevenness is possible.

  In the light emitting device 300 shown in FIGS. 6A to 6C, the base material 11 of the base body has two corners cut out at both lateral ends. The external connection terminal portions 17 of the pair of positive and negative electrodes 13 are continuously formed from the upper surface 10a of the base body, and are formed on the configuration surface of the notch portion of the base material 11 of the base body. The mounting stability of the light emitting device 400 can be improved by filling the notch with a conductive adhesive. The notch may be formed from the upper surface to the lower surface of the base material 11 of the base, or may be formed from the upper surface of the base material 11 to the middle of the end surface. In addition, this light-emitting device 300 may be turned over and mounted so that the vertical direction is reversed.

<Embodiment 4>
7A is a schematic plan view showing the light-emitting device according to Embodiment 4, and FIGS. 7B and 7C are schematic cross-sectional views showing cross sections taken along lines VIIB-VIIB and VIIC-VIIC in FIG. 7A, respectively. . As shown in FIGS. 7A to 7C, the light emitting device 400 according to Embodiment 4 includes a base 10, the light emitting element 20, and a covering member 30. The light emitting device 400 does not include the translucent member 40 and the light shielding member 50. Thus, the translucent member 40 and the light shielding member 50 are not essential components, and can be omitted.

  The base 10 includes an element mounting portion 15 on the upper surface 10a. More specifically, the base 10 is obtained by providing an electrode 13 on a base material 11. The electrode 13 includes a plurality of element mounting portions 15, external connection terminal portions 17 provided at both lateral ends of the base material 11, and lead-out wiring portions 19. The element mounting part 15 is a part where the light emitting element 20 is mounted. The external connection terminal portion 17 is a part connected to an external electrode. The lead wiring part 19 is a part for connecting the element mounting part 15 and the external connection terminal part 17. The electrode 13 is provided continuously from the upper surface 10a of the substrate 10 to the lower surface 10c through the end surface. The lead-out wiring part 19 is preferably narrower than the external connection terminal part 17 or a part of the electrode is covered with a resist (not shown) so as to be visible. Thereby, it is possible to prevent the conductive adhesive connected to the external connection terminal portion 17 or the flux contained in the paste from entering under the covering member 30.

  A plurality of light emitting elements 20 are provided. In particular, in this example, a plurality of light emitting elements 20 are arranged not only in the horizontal direction but also in the vertical direction. The light emitting element 20 is flip-chip mounted (face-down mounted) on each element mounting portion 15 of the base. More specifically, the light-emitting element 20 includes a light-emitting element structure including a semiconductor laminate, a light-transmitting substrate connected to one main surface of the light-emitting element structure, and the other (opposite side) of the light-emitting element structure. And a pair of positive and negative electrodes connected to the main surface of the side. The pair of positive and negative electrodes of the light emitting element 20 are bonded to the element mounting portion 15 of the pair of positive and negative electrodes 13 of the base by a conductive adhesive 60. Further, the upper surface 20a of the light emitting element is exposed to the outside. The upper surface 20a of the light emitting element is a back surface of a light transmitting substrate included in the light emitting element.

  The covering member 30 is white, is in contact with each light emitting element 20 and covers the periphery thereof, and is provided on the substrate 10. More specifically, the covering member 30 is obtained by solidifying a resin containing the inorganic particles 35. Note that the periphery of the light emitting element 20 means the periphery (one round) of the light emitting element 20 in a top view of the light emitting element 20. That is, “the covering member 30 is in contact with and covers the light emitting element 20” means that the covering member 30 covers all the end surfaces 20 b (side surfaces) of the light emitting element 20 while leaving the upper surface 20 a of the light emitting element 20. It means to do. Further, as illustrated, the covering member 30 preferably covers the lower surface of the light emitting element 20 in order to efficiently extract light upward from the light emitting element 20. One end surface 30b of the covering member is substantially flush with the one end surface 10b of the base. And the one end surface 30b of a coating | coated member comprises the mounting surface of the said light-emitting device 400. FIG. In particular, in this example, the one end surface 30 b of the covering member is an end surface along the longitudinal direction of the light emitting device 400.

  A hole 12 is provided in the base 10 of the light emitting device 400. The covering member 30 is filled in the hole 12 and locked to the base body 10. Thereby, the adhesiveness of the covering member 30 and the base | substrate 10 can be improved, and peeling from the base | substrate 10 of the covering member 30 can be suppressed. Thereby, the heat generated from the light emitting element 20 can be easily radiated through the covering member 30. In particular, as illustrated, the hole 12 of the base 10 is preferably formed so that the lower surface 10c side is wider than the upper surface 10a side. As a result, the covering member 30 is easily locked firmly to the base 10. The change in the width of the hole 12 of the substrate 10 may be stepped or inclined.

  The light-emitting device 400 configured as described above can also function as a side-emitting type light-emitting device. In addition, the distance between the light emitting element and the light reflector surrounding the light emitting element can be reduced, and the light emitting device can be sufficiently downsized. Moreover, the light utilization efficiency can be increased by reflecting the light emitted from the light emitting element to the front (upward) by the white covering member and taking it out. Furthermore, the light emitting device can be reduced in size while maintaining the size of the light emitting element, and a high output light emitting device can be easily obtained. Furthermore, the heat generated from the light emitting element can be dissipated through the covering member.

<Embodiment 5>
8A and 8B are a schematic plan view and a schematic side view showing the light emitting device according to Embodiment 5, respectively, and FIG. 8C is a schematic cross sectional view showing a cross section taken along line VIIIC-VIIIC in FIG. 8A. As shown in FIGS. 8A to 8C, the light-emitting device 500 according to Embodiment 5 includes a base 10, a light-emitting element 20, a covering member 30, and a translucent member 40.

  The base 10 includes an element mounting portion 15 on the upper surface 10a. More specifically, the base body 10 is two small metal pieces and serves as a pair of positive and negative electrodes 13. That is, the base 10 has a form in which the base material also serves as an electrode. The substrate 10 (electrode 13) includes an element mounting portion 15 and an external connection terminal portion 17. The element mounting part 15 is a part where the light emitting element 20 is mounted. The external connection terminal portion 17 is a part connected to an external electrode. The external connection terminal portion 17 has a recessed portion exposed to the outside, and the recessed portion is filled with a conductive adhesive, whereby the mounting stability of the light emitting device 500 can be improved. The lower surface 10 c of the base is exposed from the covering member 30.

  The light emitting element 20 is flip-chip mounted (face-down mounted) on the element mounting portion 15 of the base. More specifically, the light-emitting element 20 includes a light-emitting element structure including a semiconductor laminate, a light-transmitting substrate connected to one main surface of the light-emitting element structure, and the other (opposite side) of the light-emitting element structure. And a pair of positive and negative electrodes connected to the main surface of the side. In the light emitting element 20, a pair of positive and negative electrodes is bonded to the element mounting portion 15 of two metal pieces which are the base body 10 (electrode 13) by a conductive adhesive 60.

  The covering member 30 is a white member. The covering member 30 is obtained by solidifying a resin containing the inorganic particles 35. The covering member 30 is in contact with and covers the light emitting element 20. The covering member 30 is integrally formed with the base body 10 (electrode 13). Thus, the covering member 30 integrally holds the two metal pieces that are the base body 10 (electrode 13) in a state where they are electrically insulated from each other. Further, as illustrated, the covering member 30 preferably covers the lower surface of the light emitting element 20 in order to efficiently extract light upward from the light emitting element 20. One end surface 30b of the covering member is substantially flush with the one end surface 10b of the base. The one end face 30 b of the covering member constitutes the mounting surface of the light emitting device 500. In particular, in this example, the one end surface 30 b of the covering member is an end surface along the longitudinal direction of the light emitting device 500.

  The translucent member 40 is a translucent member provided on the light emitting element 20. More specifically, the translucent member 40 is provided in contact with the upper surface 20a of the light emitting element and the upper surface 30a of the covering member. The translucent member 40 has a convex portion in which the upper surface 40a is formed as a convex surface immediately above the light emitting element 20, and a flat portion in which the upper surface 40a is formed in a flat surface continuously around the convex portion. In addition, the one end surface of the flat part of a translucent member is substantially the same surface as the one end surface 10b of a base | substrate, and the one end surface 30b of a coating | coated member. Further, the translucent member 40 does not substantially include the phosphor 45.

  The light-emitting device 500 configured as described above can also function as a side-emitting light-emitting device. In addition, the distance between the light emitting element and the light reflector surrounding the light emitting element can be reduced, and the light emitting device can be sufficiently downsized. Moreover, the light utilization efficiency can be increased by reflecting the light emitted from the light emitting element to the front (upward) by the white covering member and taking it out. Furthermore, the light emitting device can be reduced in size while maintaining the size of the light emitting element, and a high output light emitting device can be easily obtained. Furthermore, the heat generated from the light emitting element can be dissipated through the covering member. In particular, in this example, the contact area between the metal electrode connected to the light emitting element and the mounting member can be relatively easily increased, and the heat dissipation of the light emitting device can be easily improved.

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

(Substrate 10 and composite substrate 80)
The base 10 includes an electrode 13 that is electrically connected to the light emitting element 20 and a base material 11 that holds the electrode 13. The base material 11 may also serve as the electrode 13. The electrode 13 may be a wiring or a lead frame. Examples of the material of the electrode 13 include copper, iron, nickel, tungsten, chromium, aluminum, silver, gold, titanium, and alloys thereof. In particular, copper or a copper alloy is preferable from the viewpoint of heat dissipation. A film having high light reflectivity such as silver, platinum, tin, gold, copper, rhodium, or an alloy thereof may be formed on the surface of the electrode 13. The electrode 13 is provided by plating or the like. The base material 11 is a ceramic substrate containing aluminum oxide, aluminum nitride, zirconium oxide, zirconium nitride, titanium oxide, titanium nitride or a mixture thereof, copper, iron, nickel, chromium, aluminum, silver, gold, titanium or these And a metal substrate containing an alloy of the above, a glass epoxy substrate, a BT resin substrate, a glass substrate, a resin substrate, and a paper substrate. A flexible substrate (flexible substrate) such as polyimide may be used. A white pigment such as titanium oxide may be blended in the resin of the base material 11 in order to reflect light from the light emitting element 20 efficiently. The composite substrate 80 is constituted by a plurality of substrates 10 connected in series.

(Light emitting element 20)
As the light emitting element 20, a semiconductor light emitting element such as an LED element can be used. The light emitting element 20 mainly includes a substrate, a light emitting element structure provided on the substrate, and a pair of positive and negative electrodes electrically connected to the light emitting element structure. However, the substrate can be omitted. The top view shape of the light emitting element 20 is preferably a quadrangle, particularly a rectangle, but may be other shapes. The end surface (side surface) 20b of the light emitting element 20 (particularly the substrate) may be substantially perpendicular to the upper surface 20a, or may be inclined inward or outward. The substrate is preferably translucent. For example, sapphire, spinel, silicon carbide and the like can be mentioned. The thickness of the substrate is, for example, 20 μm or more and 1 mm or less, and is preferably 50 μm or more and 500 μm or less from the viewpoint of the strength of the substrate or the thickness of the light emitting device. The light-emitting element structure is a stacked body of semiconductor layers, and preferably includes at least an n-type semiconductor layer and a p-type semiconductor layer, and further has an active layer interposed therebetween. The emission wavelength of the light-emitting element structure can be selected from ultraviolet to infrared depending on the semiconductor material and its mixed crystal ratio. In particular, it is preferable to use a nitride semiconductor (In _x Al _y Ga _1-xy N, 0 ≦ x, 0 ≦ y, x + y ≦ 1) that can excite the phosphor efficiently. In addition, a gallium arsenide semiconductor or a gallium phosphorus semiconductor that emits green to red light may be used. The light emitting element 20 is preferably provided with a pair of positive and negative electrodes on the same surface side for flip chip (face down) mounting. Further, by providing a metal layer such as silver or aluminum or a dielectric reflection film on the mounting surface side of the light emitting element 20, the light extraction efficiency can be increased. The number of light emitting elements 20 mounted on one light emitting device may be one or plural, and the size, shape, and emission wavelength may be arbitrarily selected. For example, the red, green, and blue light emitting elements 20 may be mounted on one light emitting device. The plurality of light emitting elements 20 may be arranged irregularly, but a preferable light distribution is easily obtained by arranging them regularly or periodically such as a matrix. The plurality of light emitting elements 20 can be connected in series or in parallel by the electrode 13 of the base 10.

(Coating member 30)
The covering member 30 can be made of a resin or glass containing inorganic particles 35. The resin or glass used as the base material of the covering member 30 can be the same as that of the translucent member 40 described below. Among them, a silicone resin or an epoxy resin is preferable, and a silicone resin particularly excellent in light resistance and heat resistance. Is more preferable. Since the covering member 30 can be formed by a printing method or the like, the inorganic particles 35 can be contained at a higher concentration than the conventional reflective case. The covering member 30 may be added with silica (Aerosil) or the like for adjusting the viscosity and fluidity.

(Inorganic particles 35)
The refractive index of the inorganic particles 35 is, for example, 1.8 or more, and is preferably 2 or more, more preferably 2.5 or more in order to efficiently scatter light and obtain high light extraction efficiency. preferable. The refractive index difference between the base material resin or glass of the covering member 30 and the inorganic particles 35 is, for example, 0.4 or more, and is 0.7 or more in order to efficiently scatter light and obtain high light extraction efficiency. It is preferable that it is 0.9 or more. The concentration of the inorganic particles 35 is preferably 10 weight percent concentration (wt%) or more and 60 weight percent concentration or less, preferably 20 weight percent concentration or more in consideration of preferable light reflection characteristics and ease of formation. More preferred is a 50 weight percent concentration. The average particle diameter (median diameter) of the inorganic particles 35 is preferably 0.08 μm or more and 10 μm or less, and more preferably 0.1 μm or more and 5 μm or less, at which a light scattering effect can be obtained with high efficiency. The inorganic particles 35 are preferably white. Specifically, the inorganic particles 35 are made of titanium oxide, zirconium oxide, magnesium oxide, magnesium carbonate, magnesium hydroxide, calcium carbonate, calcium hydroxide, calcium silicate, zinc oxide, barium titanate, aluminum oxide, or the like. it can. Of these, titanium oxide is preferable because it is relatively stable against moisture and has a high refractive index and excellent thermal conductivity.

(Translucent member 40)
The translucent member 40 has only to be electrically insulative and can transmit light emitted from the light emitting element 20 (preferably 70% or more). Specifically, the base material of the translucent member 40 is silicone resin, silicone modified resin, silicone modified resin, epoxy resin, phenol resin, polycarbonate resin, acrylic resin, TPX resin, polynorbornene resin, or these resins. A hybrid resin containing one or more types can be given. Glass may be used. Among these, silicone resins are preferable because they are excellent in heat resistance and light resistance. The translucent member 40 may include particles having various functions such as a filler and a phosphor in the base material. As the filler, a diffusing agent, a coloring agent, or the like can be used. Specifically, silica, titanium oxide, magnesium oxide, magnesium carbonate, magnesium hydroxide, calcium carbonate, calcium hydroxide, calcium silicate, zinc oxide, barium titanate, aluminum oxide, iron oxide, chromium oxide, manganese oxide, glass And carbon black. The shape of the filler particles may be crushed or spherical. Further, it may be hollow or porous. In addition, the translucent member 40 may be a crystal or sintered body of the phosphor 45 or a sintered body of the phosphor 45 and an inorganic binder. Further, the translucent member 40 may include a phosphor 45 in the base material, or may be a member in which the phosphor 45 is provided on the base material by application or adhesion. The translucent member 40 can be formed in a flat plate shape or a thin film shape. The light transmissive member 40 can also control the light distribution with its upper surface (surface) as a convex surface, a concave surface, or an uneven surface. The translucent member 40 may be provided on the light emitting element 20 via an adhesive.

(Phosphor 45)
The phosphor 45 absorbs at least a part of the primary light emitted from the light emitting element 20 and emits secondary light having a wavelength different from that of the primary light. Specifically, yttrium aluminum garnet (YAG) activated by cerium, lutetium aluminum garnet (LAG) activated by cerium, nitrogen-containing calcium aluminosilicate activated by europium and / or chromium (CaO- Al ₂ O ₃ —SiO ₂ ), europium activated silicate ((Sr, Ba) ₂ SiO ₄ ), and the like. Thus, a light emitting device that emits mixed light (for example, white light) of primary light and secondary light having a visible wavelength, or a light emitting device that emits visible light secondary light when excited by the primary light of ultraviolet light is used. Can do.

(Light shielding member 50)
The light shielding member 50 only needs to be capable of shielding light emitted from the light emitting element 20 and the phosphor 45 (preferably having a transmittance of 20% or less). The light shielding member 50 may be a light reflecting member such as white. In that case, the light shielding member 50 can be made of the same material as that of the covering member 30. In addition, the light shielding member 50 may be, for example, a material having a high light absorption property such as black, and in this case, the light shielding member 50 may be formed of the resin or glass containing a black pigment such as carbon black. In addition, the light shielding member 50 may be provided on the translucent member 40 through an adhesive.

(Conductive adhesive 60, 75)
The conductive adhesives 60 and 75 are conductive pastes such as silver, gold, and palladium, solders such as tin-bismuth, tin-copper, tin-silver, gold-tin, and low melting point metals. Materials can be used.

(Mounting member 70)
The mounting member 70 is a member on which the light emitting devices 100 to 500 are mounted. The mounting member 70 has a device mounting portion 73 capable of bonding the external connection terminal portions 17 of the light emitting devices 100 to 500 with a conductive adhesive 75. Specifically, the mounting member 70 includes various wiring boards and circuit boards. The specific material of the mounting member 70 can be the same as that of the substrate 10 described above. A device in which the light emitting devices 100 to 500 are mounted on the mounting member 70 is referred to as a “light source device”, for example.

(Protective element 90)
The protection element 90 is an element for protecting the light emitting element 20 from static electricity or a high voltage surge. Specifically, a Zener diode is mentioned.

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

<Example 1>
The light-emitting device of Example 1 is a side-emitting light-emitting device that has the structure shown in FIGS. 1A to 1B and can be used as a backlight light source of a liquid crystal display, for example.

  The base body 10 is formed by forming a pair of positive / negative electrodes 13 of Cu / Ni / Au (described in order from the lower layer side) on a rectangular base material 11 of BT resin, vertical 0.4 mm, horizontal 2.2 mm, thickness 0 .3mm wiring board. The pair of positive and negative electrodes 13 are close to each other in the central portion on the upper surface side of the base material 11 to constitute the element mounting portion 15. The pair of positive and negative electrodes 13 respectively extend in the horizontal direction (left / right) from the element mounting portion 15 and are formed continuously from the upper surface of the base material 11 through the end surface to the lower surface. A portion (a U-shaped portion in cross-sectional view) continuous from the upper surface to the lower surface is the external connection terminal portion 17. In addition, a portion connecting the element mounting portion 15 of the pair of positive and negative electrodes 13 and the external connection terminal portion 17 is a lead-out wiring portion 19.

  One light emitting element 20 is flip-chip mounted on the element mounting portion 15 of the base 10 by a conductive adhesive 60 that is Au—Sn eutectic solder. The light-emitting element 20 is a cuboid blue LED (emission center wavelength: 460 nm) LED chip having a nitride semiconductor element structure formed on a sapphire substrate and having a length of 0.3 mm, a width of 0.8 mm, and a thickness of 0.1 mm. It is.

  The covering member 30 is a substantially rectangular parallelepiped having an outer shape of 0.4 mm in length, 1.2 mm in width, and 0.3 mm in thickness, is in contact with the light emitting element 20 and covers the periphery thereof, and is provided on the upper surface 10 a of the base body 10. ing. The covering member 30 contains silica having an average particle diameter of 14 μm and a concentration of 2 to 2.5 wt% and, as the inorganic particles 35, titanium oxide having an average particle diameter of 0.25 to 0.3 μm and a concentration of 40 to 50 wt%. It is a cured product of silicone resin. On both sides of the covering member 30, the lead wiring portion 19 and the external connection terminal portion 17 of the electrode 13 are exposed.

  On the light emitting element 20 and the covering member 30, a translucent member 40 which is a silicone resin sheet (thickness: 0.1 mm) containing a YAG: Ce phosphor 45 is provided. Further, a light shielding member 50 having an opening having substantially the same shape as the upper surface of the light emitting element 20 is provided on the translucent member 40. The light shielding member 50 is made of the same silicone resin containing titanium oxide as the covering member 30.

  The light emitting device of this example configured as described above can achieve the same effects as the light emitting device described in the first embodiment.

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

DESCRIPTION OF SYMBOLS 10 ... Base | substrate (10a ... Upper surface, 10b ... One end surface, 10c ... Lower surface, 11 ... Base material, 12 ... Hole, 13 ... Electrode (15 ... Element mounting part, 17 ... External connection terminal part, 19 ... Lead-out wiring part))
20 ... Light emitting element (20a ... upper surface, 20b ... one end surface)
30 ... Covering member (30a ... upper surface, 30b ... one end face, 35 ... inorganic particles)
40 ... translucent member (40a ... upper surface, 40b ... one end face, 45 ... phosphor)
50 ... Light shielding member 60 ... Conductive adhesive (first conductive adhesive)
70 ... Mounting member (circuit board), 73 ... Mounting part, 75 ... Conductive adhesive (second conductive adhesive)
DESCRIPTION OF SYMBOLS 80 ... Composite substrate, 81 ... Base material of composite substrate, 83 ... Composite electrode, 85 ... Covering member formation area, 87 ... Notch, L ... Planned dividing line 90 ... Protection element 100,200,300,400,500 ... Light emission apparatus

Claims (6)

A base body whose longitudinal direction is parallel to the upper surface and one end surface;
A light emitting device including a plurality of light source units arranged in a longitudinal direction of the base body,
The light source unit is
An element mounting portion disposed on the upper surface of the substrate;
A light emitting element connected to the element mounting portion;
A white covering member that is provided on the substrate and is in contact with the light-emitting element to cover the periphery thereof, and is substantially flush with one end surface of the substrate and constitutes a mounting surface of the light-emitting device. A covering member;
A translucent member having a phosphor provided on the light emitting element and excited by light from the light emitting element;
A light emitting device comprising: The light-emitting device according to claim 1,
The base is a light emitting device including external connection terminals provided at both ends in a longitudinal direction. The light-emitting device according to claim 1 or 2,
The external connection terminal is a light-emitting device including a lead-out wiring portion that connects between the adjacent light source portions. The light-emitting device according to claim 1,
The base has an auxiliary electrode on a lower surface side, and is connected to an element mounting portion of the base through a through hole. The light-emitting device according to any one of claims 1 to 4, further comprising:
A light emitting device comprising: a light shielding member having an opening having substantially the same shape as the upper surface of the light emitting element on the light transmissive member. The light-emitting device according to claim 5,
The light-shielding member further comprises a light-shielding member provided via an adhesive.