JP2013004808A - Light emitting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light emitting device which prevents warpage of a metal container that is caused by a difference in heat expansion coefficients, achieves excellent heat radiation effect, and has a simple structure enabling a user to easily take out wiring.SOLUTION: A light emitting device has a long metal container having a bottom surface and both side surfaces and opening at an upper part thereof, and multiple light emitting elements. The multiple light emitting elements are fastened and mounted on the bottom surface of the metal container so as to be spaced a predetermined distance away from each other. Connection terminal substrates are disposed at both end parts of the metal container. The multiple light emitting elements are serially connected between the connection terminal substrates by conducting wire bonding to connect the light emitting element with the connection terminal substrate, which are located adjacent to each other, and to connect the light emitting elements with each other.

Description

  The present invention relates to a light emitting device, and more particularly to a light emitting device in which a plurality of light emitting elements are arranged in a line and used as a backlight of a liquid crystal display device or a light source for various illuminations.

  In recent years, with the advent of blue light-emitting diodes (LEDs), light-emitting devices using light-emitting elements (LEDs) are used in various lighting devices and mobile phone devices due to their low power consumption and long life. It is mounted on many representative electronic devices and various control devices. A single light-emitting element used for light sources for various lighting equipment, key lighting for electronic equipment, backlight light sources, etc. is insufficient for a single light-emitting device, so a light-emitting device that uses multiple light-emitting elements as a light source is used. Has been. When the luminance of illumination is increased using such a plurality of light emitting elements, heat generation of the light emitting elements increases, and it is necessary to quickly dissipate the heat. Thus, a light emitting device in which a plurality of light emitting elements are arranged in a straight line is disclosed as a high luminance light emitting device for the purpose of improving heat dissipation characteristics.

  FIG. 14 is a perspective view showing a light emitting device in the first conventional example. As shown in FIG. 14, the light emitting device 10 in the conventional example has light emitting elements 2a, 2b, 2c and wiring boards 3a, 3b, 3c, 3d alternately and linearly on the bottom of the long groove 1a of the substrate 1 having the long groove 1a. These are electrically connected in series by bonding wires 4a, 4b, 4c and 4d. In addition, power supply wirings 5a and 5b are connected to the outermost wiring boards 3a and 3d. The long groove 1a of the substrate 1 is filled with a translucent resin 6, and the light emitting elements 2a, 2b, 2c and the like are sealed.

  15 is a cross-sectional view of the light emitting device in FIG. As shown in FIG. 15, three light emitting elements 2 a, 2 b, 2 c are attached to the substrate 1 with a transparent silicone adhesive layer 9. The four wiring boards 3a, 3b, 3c, and 3d are printed wiring boards, which are composed of an insulating board 8 and a conductive layer 7 formed thereon, and are attached to the board 1 with silicone paste (not shown) or the like. Has been. In addition, since the board | substrate 1 is using Al substrate etc. of high reflectance and high thermal conductivity, it is excellent in heat dissipation and can increase the brightness | luminance of light emitting element 2a, 2b, 2c (for example, refer patent document 1). .

JP 2011-61056 A (page 4-6, FIG. 1-4)

  However, the light emitting device 10 in the conventional example has a complicated structure because each light emitting element 2a, 2b, 2c is arranged between the wiring boards 3a, 3b, 3c, 3d at the bottom of the long groove 1a of the substrate 1. There was a problem. Further, there is a problem that the substrate 1 may be warped during heat treatment due to the difference in thermal expansion coefficient between the substrate 1 and the wiring substrates 3a, 3b, 3c, and 3d. Furthermore, since the outermost wiring boards 3a and 3d are sealed with the phosphor resin 6, it is necessary to connect the power supply wirings 5a and 5b to the wiring boards 3a and 3d in advance before the sealing step. There is a problem that the wiring is complicated.

(the purpose)
The present invention has been made in view of the above problems, and prevents light from being bent due to a difference in coefficient of thermal expansion, has an excellent heat dissipation effect, has a simple structure, and allows easy wiring extraction. An object is to provide an apparatus.

  In order to solve the above problems, a light-emitting device of the present invention has a long metal container having a bottom surface and both side surfaces and opened upward, and a plurality of light-emitting elements. A plurality of light emitting elements are mounted by fixing and mounting the light emitting elements at predetermined intervals, and arranging connection terminal substrates at both ends of the metal container, and wire bonding the adjacent light emitting elements to the connection terminal substrate and the light emitting elements. Are connected in series between the connection terminal boards.

  Further, the inside of the metal container is filled with a translucent resin except for at least a part of the connection electrodes of the connection terminal substrate.

  The translucent resin is a phosphor-containing resin mixed with fluorescent particles.

  The translucent resin is composed of a phosphor-containing resin coated around each light emitting element and a transparent resin filled in the metal container.

  In addition, a part of the connection terminal board is disposed so as to protrude from an end of the metal container.

  The end of the metal container has a protrusion on the bottom, and a connection terminal board is disposed on the protrusion.

  Further, the metal container is an aluminum container having a U-shaped cross section.

  In addition, a dummy chip is provided between the light emitting elements, and the adjacent light emitting elements are electrically connected by wire bonding via the dummy chip.

  The dummy chip has a substrate made of silicone or sapphire and a dummy electrode provided on the substrate.

  According to the present invention, it is possible to realize a light emitting device that can prevent warpage of a metal container caused by a difference in thermal expansion coefficient, has an excellent heat dissipation effect, has a simple structure, and allows easy wiring extraction. it can.

The light-emitting device in the 1st Embodiment of this invention is shown, Fig.1 (a) is a perspective view, FIG.1 (b) is the top view seen from the upper surface side. It is AA sectional drawing of the light-emitting device in Fig.1 (a). It is BB sectional drawing of the light-emitting device in Fig.1 (a). It is the elements on larger scale which show the wiring state of the light-emitting device in FIG.1 (b). It is sectional drawing which shows the other example of the light-emitting device in the 1st Embodiment of this invention. It is a perspective view which shows the metal container of the light-emitting device in the 1st Embodiment of this invention. It is sectional drawing which shows the other example of the metal containers of the light-emitting device in the 1st Embodiment of this invention. It is a perspective view which shows the light-emitting device in the 2nd Embodiment of this invention. It is the top view which looked at the light-emitting device in FIG. 8 from the upper surface side. It is CC sectional drawing of the light-emitting device in FIG. It is a perspective view which shows the metal container of the light-emitting device in the 2nd Embodiment of this invention. It is a top view which shows the light-emitting device in the 3rd Embodiment of this invention. It is the elements on larger scale which show the wiring state of the light-emitting device in FIG. It is a perspective view which shows the light-emitting device in a prior art example. It is sectional drawing which shows the light-emitting device in a prior art example.

(First embodiment)
1A and 1B show a light emitting device according to a first embodiment of the present invention, in which FIG. 1A is a perspective view and FIG. 1B is a plan view seen from the upper surface side. 2 is a cross-sectional view taken along line AA of the light-emitting device in FIG. 1, and FIG. 3 is a cross-sectional view taken along line BB of the light-emitting device in FIG. Hereinafter, specific embodiments will be described with reference to the drawings.

  As shown in FIGS. 1, 2, and 3, the light emitting device 20 in the present embodiment has a bottom portion 14 and side walls 12 and 13 that rise from both sides of the bottom portion 14, respectively, and is a long metal that opens upward. A plurality of light emitting elements 17 fixedly mounted on a bottom surface 14a inside the bottom portion 14 of the metal container 11 at a predetermined interval, and a bottom surface 14a at both end portions 11a and 11b of the metal container 11 Connection terminal boards 15 and 16 are provided. Further, the adjacent light emitting elements 17 and the connection terminal substrates 15 and 16 adjacent to the light emitting elements 17 are wire-bonded and electrically connected by wires 18. As a result, the plurality of light emitting elements 17 are connected in series between the connection terminal substrates 15 and 16.

  The plurality of light emitting elements 17 are bonded and arranged with a heat conductive adhesive (not shown) in a state of being insulated from the bottom surface 14 a of the metal container 11. One connection terminal board 15 is a printed wiring board, and includes an insulating board 15a and a connection electrode 15b formed thereon. One of the bottom terminals 14a of the metal container 11 is made of silicone paste (not shown). The end portion 11a is mounted adjacent to the outermost light emitting element 17. Similarly, the other connection terminal board 16 is composed of an insulating board 16a and a connection electrode 16b, and is mounted on the other end 11b of the bottom surface 14a of the metal container 11.

  FIG. 4 is a partially enlarged view showing a wiring state of the light emitting device in FIG. As shown in FIG. 4, the light emitting element 17 includes a p-side electrode 17a and an n-side electrode 17b. In the light emitting element 17 adjacent to one connection terminal substrate 15, the connection electrode 15 b of one connection terminal substrate 15 and the p-side electrode 17 a of the adjacent light emitting element 17 are electrically connected by a wire 18. Further, the n-side electrode 11 b of the light emitting element 17 is electrically connected to the p-side electrode 17 a of another adjacent light emitting element 17 by a wire 18. Similarly, a plurality of other light emitting elements 17 are wire-bonded by the wires 18 adjacent to each other and electrically connected in series. In addition, the light emitting element 17 adjacent to the other connection terminal substrate 16 is electrically connected to the connection electrode 16b of the other connection terminal substrate 16 and the n-side electrode 17b of the light emitting element 17 adjacent by the wire 18. .

  Furthermore, the inside of the metal container 11 surrounded by the side surfaces 12a, 13a and the bottom surface 14a inside the side walls 12, 13 of the metal container 11 is filled with a translucent resin 19 made of silicone resin. As a result, the light-emitting element 17, the wire 18, and the connection terminals 15 and 16 of the connection terminal boards 15 and 16 are partially sealed and sealed with the light-sensitive resin 19. That is, only a portion of the connection electrode 15a of one connection terminal substrate 15 connected to the light emitting element 17 and the wire 18 is sealed, and the other portion is exposed. Similarly, with respect to the other connection terminal substrate 16, only the portion of the connection electrode 16a connected to the light emitting element 17 and the wire 18 is sealed, and the other portion is exposed. Since the power supply wiring can be connected to a part of the exposed connection electrodes 15a and 16a, the wiring can be easily taken out. In addition, although all the connection electrodes 15a and 16a may be exposed, it is preferable to seal the portion connected by the light emitting element 17 and the wire 18 because the connection between the light emitting element 17 and the wire 18 can be stabilized.

Further, as a material for filling the inside of the metal container 11, in addition to the above-described translucent resin 19, a phosphor-containing resin mixed with fluorescent particles as necessary may be filled.
FIG. 5 is a cross-sectional view of a light-emitting device showing another example of a translucent resin filling the inside of a metal container. As shown in FIG. 5, the light-emitting device 30 is an example in which a phosphor-containing resin 27 is formed so as to cover the periphery of the light-emitting element 17, and then the diffusing agent-containing resin 29 is filled into the metal container 11. . Note that the above-described translucent resin 19 may be used instead of the diffusing agent-containing resin 29.

  FIG. 6 is a perspective view showing the metal container 11. As shown in FIG. 6, the metal container 11 is a long container made of an aluminum material having a U-shaped cross section, and includes side walls 12 and 13 that rise from both sides of the bottom portion 14. Side surfaces 12a and 13a inside the side walls 12 and 13 are formed to be substantially perpendicular to the bottom surface 14a.

  FIG. 7 is a cross-sectional view showing another example of a metal container. As shown in FIG. 7, the side surfaces 22a and 23a are inclined so that the value of the distance b between the side surface 22a inside the side walls 22 and 23 of the metal container 21 and the side surface 23a increases upward from the bottom surface 14a. You may form in. In addition, about the material of the metal containers 11, the metal material with favorable heat conductivity other than an aluminum material can also be used.

  As described above, the light emitting device 20 of the present embodiment has excellent heat dissipation because the light emitting element 17 is directly mounted and fixed to the bottom surface 14a of the metal container 11. In addition, since the plurality of light emitting elements 17 are fixed to the bottom surface 14a at a predetermined interval to connect the light emitting elements 17 in series and the connection terminal boards 15 and 16 are arranged at the end of the metal container 11, the structure is Simplification and prevention of warping of the metal container 11 caused by a difference in thermal expansion coefficient can be ensured. Further, the connection terminal substrates 15 and 16 are disposed at the end portions 11 a and 11 b of the metal container 11, and a part of the connection electrodes 15 a and 16 a of the connection terminal substrate is not sealed with the translucent resin 19. Since it is exposed, there is an effect that the wiring can be easily taken out.

(Second Embodiment)
8 is a perspective view of the light emitting device according to the second embodiment of the present invention, FIG. 9 is a plan view seen from the upper surface side of the light emitting device, and FIG. 10 is a cross-sectional view taken along the line C-C of the light emitting device in FIG. The light emitting device according to the second embodiment is different from the first embodiment in that a part of the connection terminal board is disposed so as to protrude from the end of the metal container, and the other points are the first embodiment. It is the same. Therefore, the same reference numerals are assigned to the same components and the description thereof is omitted. Hereinafter, specific embodiments will be described with reference to the drawings.

  First, the metal container of the light emitting device in the second embodiment will be described. FIG. 11 is a perspective view showing a metal container of the light emitting device according to the second embodiment. As shown in FIG. 11, the metal container 31 in this embodiment is provided with projecting portions 35 and 36 so that the bottom portion 14 projects from both end portions 31a and 31b, and upper surfaces 35a and 36a of the projecting portions 35 and 36. And the bottom surface 14a of the bottom portion 14 are formed on the same plane.

  Next, a light emitting device in the second embodiment will be described. As shown in FIGS. 8 to 10, the light emitting device 40 according to the present embodiment includes the connection terminal substrates 15 and 16 on the upper surfaces 35 a and 36 a of the projecting portions 35 and 36 that project from both end portions 31 a and 31 b of the metal container 31. Has been placed. The connection terminal boards 15 and 16 are arranged such that a part thereof is positioned on the upper surfaces 35 a and 36 a of the projecting portions 35 and 36 and the remaining part is positioned on the bottom surface 14 a of the metal container 31. A plurality of light emitting elements 17 are connected in series and fixedly mounted between one connection terminal board 15 and the other connection terminal board 16 in the same manner as in the first embodiment. Further, the inside of the metal container 31 is filled with a translucent resin 19 made of silicone resin and the light emitting element 17 and the like are sealed, but the connection terminal substrate 15 located on the upper surfaces 35a and 36a of the projecting portions 35 and 36. , 16 are exposed without being sealed by the translucent resin 19. Since other points are the same as those in the first embodiment, description thereof is omitted.

  As described above, in the light emitting device 40 according to the second embodiment, the connection terminal substrates 15 and 16 are formed on the upper surfaces 35a and 36a of the protrusions 35 and 36 of the metal container 31, and one of the connection electrodes 15a and 16a is formed. Since the portion is exposed without being sealed by the translucent resin 19, the wiring can be easily taken out. In this embodiment, the same effect as that of the first embodiment can be obtained.

(Third embodiment)
FIG. 12 is a plan view of a light emitting device according to the third embodiment of the present invention, and FIG. 13 is a partially enlarged view showing a wiring state of the light emitting device in FIG. The light emitting device according to the third embodiment is different from the first embodiment in that dummy chips are arranged between the connection terminal substrate and the adjacent light emitting elements and between the adjacent light emitting elements. The point is the same as in the first embodiment. Therefore, the same reference numerals are assigned to the same components and the description thereof is omitted. Hereinafter, specific embodiments will be described with reference to the drawings.

  As shown in FIG. 12, the light emitting device 50 in the present embodiment has dummy chips 24 arranged between the connection terminal substrates 15 and 16 and the adjacent light emitting elements 17 and between the adjacent light emitting elements 17, respectively. The light emitting elements 17 adjacent to the connection terminal boards 15 and 16 and the light emitting elements 17 adjacent to each other are wire-bonded via a dummy chip 24 and electrically connected in series. Each dummy chip 24 is bonded and disposed with a heat conductive adhesive (not shown) in a state of being insulated from the bottom surface 14 a of the metal container 11 in the same manner as the light emitting element 17.

  FIG. 13 is a partially enlarged view showing a wiring state of the light emitting device 50 in FIG. As shown in FIG. 13, the dummy chip 24 includes a dummy electrode 24b provided on a dummy substrate 24a made of a silicone material. The light emitting element 17 arranged via one connection terminal substrate 15 and the dummy chip 24 is the connection electrode 15b of one connection terminal substrate 15 and the p-side electrode 17a of the light emitting element 17 are dummy electrodes of the dummy chip 24. 24b and the wire 18 are electrically connected. Further, the n-side electrode 17 b of the light-emitting element 17 and the p-side electrode 17 a of the other light-emitting element 17 arranged via the other dummy chip 24 are electrically connected by the dummy electrode 24 b of the other dummy chip 24 and the wire 18. It is connected. Similarly, a plurality of other light-emitting elements 17 are wire-bonded by wires 18 via the dummy chips 24 between the light-emitting elements 17 adjacent to each other and electrically connected in series. The light emitting element 17 arranged via the other connection terminal substrate 16 and the dummy chip 24 is different from the connection electrode 16 b of the other connection terminal substrate 16 and the n-side electrode 17 b of the light emitting element 17 of the dummy chip 24. The dummy electrode 24b and the wire 18 are electrically connected.

  As described above, the light emitting device 50 according to the present embodiment wire-connects the connection terminal substrates 15 and 16 with the light emitting elements 17 disposed via the dummy chips 24 and the light emitting elements 17 disposed via the dummy chips 24. By bonding, the plurality of light emitting elements 17 are electrically connected in series between the connection terminal substrates 15 and 16 via the dummy chip 24.

  In addition, although the silicone material was demonstrated to the dummy substrate 24a of the dummy chip 24 as an example, you may use a sapphire material. Since other points are the same as those in the first embodiment, description thereof is omitted. In this embodiment, the example in which the dummy chip 24 is provided between the connection terminal substrates 15 and 16 and the adjacent light emitting element 17 has been described. However, the light emitting element 17 adjacent to the connection terminal substrates 15 and 16 and These may be electrically connected by direct wire bonding as in the first embodiment.

  As described above, in the light emitting device 50 according to the third embodiment, since the plurality of light emitting elements 17 are wire-bonded via the dummy chip 24, compared to the case where the plurality of light emitting elements 17 are directly wire-bonded. The length of the wire 18 can be reduced. This is effective when the brightness is not so high and the interval between the light emitting elements 17 becomes large. Further, since the dummy substrate 24a of the dummy chip 24 is made of a silicone material or a sapphire material like the light emitting element 17, it is possible to prevent the metal container 11 from being warped due to a difference in thermal expansion coefficient.

  Further, the connection terminal boards 15 and 16 have been described by taking the printed wiring board as an example, but connection electrodes may be formed on a silicon substrate or a sapphire substrate in the same manner as the dummy chip 24. In this case, since all the materials of the substrate disposed on the bottom surface 14a of the metal container 11 are silicone material or sapphire material, it is possible to more reliably prevent the metal container 11 from being warped due to a difference in thermal expansion coefficient. it can. This is particularly effective when the external electrical connection is made with a probe pin or a spring. In this embodiment, the same effect as that of the first embodiment can be obtained.

  In addition, although it did not demonstrate in particular about the light emitting element in each embodiment, red LED, green LED, blue LED, etc. can be selected suitably. In addition, a phosphor-containing resin made of a silicone resin containing various phosphors corresponding to the selected light-emitting element can also be used for the translucent resin filled in the metal container.

11, 21, 31 Metal container 11a, 11b, 31a, 31b Metal container end 12, 13, 22, 23 Metal container side wall 12a, 13a 22a, 23a Inside side wall 14 Side surface of metal container Bottom portion 14a Bottom surface 15, 16 Connection terminal substrate 15a, 16a Insulating substrate 15b, 16b Connection electrode 17 Light emitting element 17a P-side electrode 17b N-side electrode 18 Wire 19 Translucent resin
20 30, 40 Light-emitting device 24 Dummy chip 24a Dummy substrate 24b Dummy electrode 27 Phosphor-containing resin 29 Diffusing agent-containing resin 35, 36 Projecting portions 35a, 36a Upper surface of the projecting portion

Claims (9)

  A long metal container having a bottom surface and both side surfaces and having an open top surface, and a plurality of light emitting elements, and a plurality of light emitting elements are fixedly mounted on the bottom surface of the metal container at predetermined intervals, and A plurality of light emitting elements are connected in series between the connection terminal boards by arranging connection terminal boards on both ends of the metal container and wire bonding the adjacent light emitting elements to the connection terminal boards and the light emitting elements. Light-emitting device.   The light emitting device according to claim 1, wherein the inside of the metal container is filled with a translucent resin except for at least a part of the connection electrode of the connection terminal substrate.   The light-emitting device according to claim 2, wherein the translucent resin is a phosphor-containing resin mixed with fluorescent particles.   The said translucent resin was comprised with the fluorescent substance containing resin coat | covered around the said each light emitting element, and the transparent resin with which the inside of the said metal container was filled, The Claim 2 characterized by the above-mentioned. Light emitting device.   5. The light-emitting device according to claim 1, wherein a part of the connection terminal substrate protrudes from an end portion of the metal container.   The light emitting device according to claim 5, wherein an end portion of the metal container has a protruding portion on a bottom surface, and a connection terminal substrate is disposed on the protruding portion.   The light emitting device according to any one of claims 1 to 6, wherein the metal container is an aluminum container having a U-shaped cross section.   8. The semiconductor device according to claim 1, wherein a dummy chip is provided between the light emitting elements, and the adjacent light emitting elements are electrically connected by wire bonding via the dummy chip. The light emitting device according to item.   The light emitting device according to claim 8, wherein the dummy chip includes a substrate made of silicone or sapphire and a dummy electrode provided on the substrate.

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