JP2012209537A - Lighting apparatus, display, and signal light - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lighting apparatus, a display, and a signal light that can improve heat dissipation characteristics.SOLUTION: A lighting apparatus according to the present invention includes a rectangle supporting substrate 1 and a plurality of light-emitting devices 2 arranged on the supporting substrate 1 in a matrix shape. Each light-emitting device 2 has a light-emitting element 3 emitting light with a predetermined hue, two through electrodes 12a and 12b for electrically connecting the light-emitting element 3, and a plurality of columnar heat sinks 11 arranged around the light-emitting element 3 for heat radiation. Each light-emitting element 3 is provided in a recess 10 formed on a plate surface of the supporting substrate 1. The columnar heat sinks 11 penetrate in the thickness direction of the supporting substrate 1, are arranged in a matrix shape at a minute distance from one another, and are connected to radiators provided on the rear surface (the other surface) of the supporting substrate 1. For this reason, the columnar heat sinks 11 can effectively dissipate heat from the substrate 1.

Description

  The present invention relates to a lighting device, a display, and a signal lamp using a light emitting diode.

  A light emitting device using a light emitting diode has advantages such as energy saving and long life, and has attracted attention as a light source such as a lighting device, a color image display device, a liquid crystal display backlight, or a traffic light.

  For this type of light emitting device, conventionally, an LED chip configured as a flip chip (FC) is mounted on a submount substrate, and this assembly is further mounted on a packaging substrate and formed on the submount substrate. The electrode and the electrode formed on the packaging substrate were connected by wire bonding.

  However, this assembly structure increases the cost because a submount substrate made of an expensive material such as AlN must be used. In addition, since the electrodes formed on the submount substrate and the electrodes formed on the packaging substrate must be connected by wire bonding, a wire bonder device and a wire bonding device are required, which increases production equipment costs. However, this has been passed on to the product cost, leading to high costs for light emitting devices.

  As means for solving the above-described problems, Patent Document 1 discloses that a groove is formed on one surface of a silicon submount, two vias (through electrodes) are formed at the bottom of the groove, and an LED die is placed in the groove. A method of manufacturing an LED package that is flip chip mounted and filled with grooves with a protective adhesive is disclosed.

  However, no consideration is given to a heat dissipation structure that releases heat generated during the light emitting operation of the LED die. In general, LED devices have low power consumption, but the amount of no infrared radiation is emitted as thermal energy, and since the light emitting elements are covered with solids, the heat dissipation becomes solid thermal conductivity. Because the surface area of the LED component is small and the surface area of the LED component is small, sufficient heat conduction area, convection area, and radiation area cannot be obtained, and furthermore, heat dissipation components such as conventional heat sinks cannot be attached, making it difficult to design heat dissipation It is said that it is.

  Accordingly, when a lighting device that needs to have a plurality of LEDs mounted thereon and that does not have a sufficient heat dissipation structure such as the LED package described above, the LED die and the via are connected by the heat generated in the LED die. The bonding strength of the bonding portion may be lost, and the reliability of electrical connection may be impaired, or the light emission characteristics of the LED die may vary. In this regard, Patent Documents 2 and 3 employ a thermal via as a structure for releasing heat generated in the light emitting device, but do not have a heat dissipation structure assuming a through electrode.

  Further, as shown in Patent Document 1, when the via (through electrode) is formed by electroplating or vapor deposition, the processing time is inevitably long, and thus the production efficiency is deteriorated. As a means for avoiding such a problem, it is conceivable to form vias by embedding a conductive paste in the through hole. However, the conductive paste embedded in the through hole is always contracted during solidification, and the shrinkage nest is not formed. Will occur. Such shrinkage nests cause an increase in electrical resistance and a decrease in reliability.

  Further, there is a need for means for efficiently radiating the light generated in the LED die to the outside, but Patent Document 1 does not disclose such means.

JP 2009-111006 A JP 2005-158957 A JP 2010-233891 A

  The subject of this invention is providing the illuminating device, display, and signal lamp which can improve a thermal radiation characteristic.

  In order to solve the above-described problem, an illumination device according to the present invention includes a support substrate and a plurality of light emitting elements. The support substrate is provided with a plurality of light emitting element installation regions on the plate surface, and includes a plurality of through electrodes and a plurality of columnar heat sinks.

  The plurality of through-electrodes are arranged two by two so as to penetrate the support substrate in the thickness direction and to have one end exposed in each of the plurality of light-emitting element installation regions. The plurality of columnar heat sinks are provided in the thickness direction of the support substrate.

  Each of the plurality of light-emitting elements includes a structure in which a P-type semiconductor layer and an N-type semiconductor layer are stacked, and is disposed in a light-emitting element installation region of the support substrate, and a P-side electrode of the P-type semiconductor layer passes through the through-hole. The one end of the electrode is connected to the one end, and the N-side electrode of the N-type semiconductor layer is connected to the other end of the through electrode. The support substrate includes a silicon layer, and the plurality of columnar heat sinks are arranged around the light emitting element so as to penetrate the silicon layer and are spaced apart from each other, and are provided between the support substrate and the support substrate. The electrically insulating layer is electrically insulated from the support substrate, and one end of each of the plurality of columnar heat sinks is commonly connected to a heat radiator provided on the other surface of the support substrate.

  As described above, the lighting device according to the present invention includes a support substrate, and the support substrate includes a plurality of columnar heat sinks. Since the columnar heat sink is provided in the thickness direction of the support substrate, heat generated by the light emitting operation of the light emitting element can be radiated to the outside of the support substrate by the columnar heat sink.

  The columnar heat sink is distributed with a predetermined area occupancy with respect to the plate surface of the support substrate. Therefore, by appropriately selecting the thermal resistance of the material constituting the columnar heat sink and the occupation ratio of the columnar heat sink, the heat generated by the light emitting operation of the light emitting element is efficiently radiated to the outside of the support substrate by the column heat sink. Yeah.

  In the lighting device according to the present invention, the support substrate includes a plurality of through electrodes and has a plurality of light emitting element installation regions on the plate surface. Two through-electrodes are arranged through the support substrate in the thickness direction, and two each of the through-electrodes are exposed in each of the plurality of light emitting element installation regions. A light emitting element is disposed in the light emitting element installation region of the support substrate.

  The light emitting element has a structure in which a P-type semiconductor layer and an N-type semiconductor layer are stacked. In the light emitting element installation region, the P-side electrode of the P-type semiconductor layer is connected to one end of the through electrode, and the N-side electrode of the N-type semiconductor layer is connected to the other end of the through electrode. Therefore, according to the present invention, it is possible to realize a structure in which the electrode of the light emitting element does not appear on the light emitting surface, so that the light of the light emitting element can be efficiently emitted to the outside.

  The liquid crystal display according to the present invention includes a liquid crystal panel and a backlight. The backlight is the illumination device described above, and illuminates the liquid crystal panel from the back.

  Since the liquid crystal display according to the present invention includes the above-described illumination device, the above-described effects can be obtained.

  The scope of application of the technical idea of the present invention is not limited to the illumination device and the liquid crystal display.

  The light emitting diode display according to the present invention includes a support substrate and a plurality of light emitting elements. The support substrate is provided with a plurality of light emitting element installation regions on the plate surface, and includes a plurality of through electrodes and a plurality of columnar heat sinks.

  The plurality of through-electrodes are arranged two by two so as to penetrate the support substrate in the thickness direction and to have one end exposed in each of the plurality of light-emitting element installation regions. The plurality of columnar heat sinks are provided in the thickness direction of the support substrate and are distributed with a predetermined area occupancy with respect to the plate surface.

  Each of the plurality of light-emitting elements includes a structure in which a P-type semiconductor layer and an N-type semiconductor layer are stacked, and is disposed in the light-emitting element installation region of the support substrate, and a P-side electrode of the P-type semiconductor layer is One end of the through electrode is connected to the one end, and the N-side electrode of the N-type semiconductor layer is connected to the other end of the through electrode.

  Further, the support substrate includes a silicon layer, and the plurality of columnar heat sinks are arranged around the light emitting element so as to penetrate the silicon layer and are spaced apart from each other. The insulating substrate is electrically insulated from the support substrate, and one end of each of the plurality of columnar heat sinks is commonly connected to a heat radiator provided on the other surface of the support substrate.

  Since the light-emitting diode display according to the present invention includes the same configuration as that of the above-described lighting device, the above-described effects can be obtained.

  Furthermore, the signal lamp according to the present invention includes a support substrate and a plurality of light emitting elements. The support substrate is provided with a plurality of light emitting element installation regions on the plate surface, and includes a plurality of through electrodes and a plurality of columnar heat sinks.

  The plurality of through-electrodes are arranged two by two so as to penetrate the support substrate in the thickness direction and to have one end exposed in each of the plurality of light-emitting element installation regions. The plurality of columnar heat sinks are provided in the thickness direction of the support substrate and are distributed with a predetermined area occupancy with respect to the plate surface.

  Each of the plurality of light-emitting elements includes a structure in which a P-type semiconductor layer and an N-type semiconductor layer are stacked, and is disposed in a light-emitting element installation region of the support substrate, and a P-side electrode of the P-type semiconductor layer passes through the through-hole. The one end of the electrode is connected to the one end, and the N-side electrode of the N-type semiconductor layer is connected to the other end of the through electrode.

  Further, the support substrate includes a silicon layer, and the plurality of columnar heat sinks are arranged around the light emitting element so as to penetrate the silicon layer and are spaced apart from each other. The insulating substrate is electrically insulated from the support substrate, and one end of each of the plurality of columnar heat sinks is commonly connected to a heat radiator provided on the other surface of the support substrate.

  Since the signal lamp according to the present invention includes the same configuration as that of the lighting device described above, the above-described effects can be obtained.

  As described above, according to the present invention, it is possible to provide an illumination device, a display, and a signal lamp that can improve heat dissipation characteristics.

It is a top view of the illuminating device which concerns on this invention. It is a top view of the light-emitting device which comprises the illuminating device shown by FIG. It is sectional drawing which follows the III-III line | wire shown by FIG. FIG. 4 is a cross-sectional view in which a light emitting element and a phosphor are removed from the cross-sectional view of FIG. 3. It is a side view of the light emitting element which comprises a light emitting device. FIG. 6 is a bottom view of the light emitting device shown in FIG. 5. It is sectional drawing of the light-emitting device which concerns on another form. It is sectional drawing which remove | excluded the light emitting element and the fluorescent substance from sectional drawing of FIG. It is sectional drawing of the liquid crystal display which concerns on this invention. It is a top view of a pixel. 1 is a plan view of a light emitting diode display according to the present invention.

  FIG. 1 is a plan view of a lighting device according to the present invention. The illumination device according to the present invention includes a rectangular support substrate 1 and a plurality of light emitting devices 2 arranged in a matrix on the support substrate 1.

  Each light emitting device 2 is arranged around the light emitting element 3 for emitting heat, a light emitting element 3 emitting light of a predetermined hue, two through electrodes 12a and 12b for electrically connecting the light emitting element 3 A plurality of columnar heat sinks 11. Each light emitting element 3 is provided in a recess 10 which is a light emitting element installation region formed on the plate surface of the support substrate 1. The shape of the support substrate 1, the number of light emitting devices 2, the arrangement form, the number of columnar heat sinks 11, and the arrangement form are not limited to those shown in FIG. 1 and should be determined appropriately.

  2 to 4 show the light emitting device 2 in detail. The support substrate 1 is a so-called package, and includes a plurality of through electrodes 12a and 12b and a plurality of columnar heat sinks 11, and has a recess 10 on the plate surface. The support substrate 1 is preferably made of Si as a main component, but is not limited thereto, and may be an insulating resin substrate or an insulating ceramic substrate. Furthermore, a conductive substrate such as a metal substrate may be used. In the present embodiment, a case where the support substrate 1 is a silicon layer will be described as an example.

  The shape of the recess 10 of the support substrate 1 is not limited to the rectangular parallelepiped shape as shown in FIG. 4, and may be another shape. The recess 10 is formed so as to surround the through-electrodes 12a and 12b at a distance when the support substrate 1 is viewed in plan view. For example, an Al film or an Ag film is formed on almost the entire inner surface of the recess 10. Alternatively, the reflective film 4 made of a Cr film or the like is formed by sputtering or the like. The reflective film 4 is not limited to the above-described form. For example, the reflective film 4 may be attached to the side surface of the light emitting element 3, and an insulating film such as an oxide film may be provided below the reflective film 4.

  The light emitting element 3 is fitted in the recess 10 with a minute clearance. According to this structure, the positioning and arrangement of the light emitting element 3 with respect to the support substrate 1 can be easily and reliably executed.

  Further, the upper surface of the light emitting element 3 is covered with the fluorescent layer 5 in the recess 10. Thereby, the brightness | luminance of the light which the light emitting element 3 emits can be improved. An example of the fluorescent material used for the fluorescent layer 5 is calcium phosphate. Further, the hue of the fluorescent layer 5 should be appropriately determined according to the application.

  Each of the through electrodes 12 a and 12 b penetrates the support substrate 1 in the thickness direction within the bottom surface of the recess 10, one end is exposed on the inner surface of the recess 10, and the other end is exposed on the other surface of the support substrate 1. The through-electrodes 12a and 12b are solid columnar bodies filled with contents, and can have an arbitrary cross-sectional shape such as a square shape or a circular shape. Further, the end surface shapes of the through electrodes 12a and 12b may correspond to the electrode shapes of the light emitting elements 3 to be connected. In this case, the end surface shapes of the through electrodes 12a and 12b are a circular shape and a quadrangular shape, respectively.

  Since the support substrate 1 in this embodiment is a silicon layer, the through electrodes 12 a and 12 b are electrically insulated from the support substrate 1. As means for electrical insulation, electrical insulating layers 13a and 13b are provided between the outer peripheral surfaces of the through electrodes 12a and 12b and the inner peripheral surfaces of the vertical holes in which the through electrodes 12a and 12b are arranged. The electrical insulating layers 13a and 13b may be an oxide film or a nitride film obtained by oxidizing or nitriding the inner wall surface of the vertical hole of the support substrate 1 made of a silicon layer, or an organic insulating material filled in the vertical hole. Or a layer made of an inorganic insulator such as glass or glass.

  The through electrodes 12a and 12b are made of a solidified metal body, for example. An advantage of using the solidified metal body is that a molten metal filling method in which a molten metal is poured into a vertical hole provided in the support substrate 1 and solidified can be applied. The molten metal filling method is disclosed in Japanese Patent No. 4278007. By applying this molten metal filling method, the molten metal poured into the vertical hole is cooled and solidified while applying mechanical force, for example, press pressure, injection pressure or rolling pressure using a press plate. As a result, the through electrodes 12a and 12b having a dense structure free of nests, voids, and cavities can be efficiently formed in a short time.

  Bi, In, Sn, and Cu can be exemplified as the main metal materials used when the through electrodes 12a and 12b are formed using a molten metal filling method. In particular, when Bi is contained, dense through-electrodes 12a and 12b that do not generate cavities or voids inside the vertical holes can be formed due to the volume expansion characteristics of Bi during solidification. However, when Bi or the like is included, the electric resistance tends to increase. Therefore, Bi is preferably used as long as the required electric resistance value is satisfied.

  As the molten metal, it is possible to use a material obtained by melting a nanoparticle powder having a nanocomposite crystal structure composed of an aggregate of polycrystals having a particle size of 1 μm or less using the above-described metal material. As described above, by including nanoparticles whose size is limited to the nano level, it is possible to form the through electrodes 12a and 12b by filling the molten metal in the fine vertical holes. In the nanocomposite crystal structure, (a) nanoparticles having a eutectic structure are dispersed inside the non-eutectic structure, (b) nanoparticles having a eutectic structure are dispersed in the grain boundaries of the non-eutectic structure. (C) Dispersing nanoparticles composed of a non-eutectic structure at the grain boundaries of the eutectic structure, (d) Dispersing nanoparticles composed of the eutectic structure inside the non-eutectic structure, Examples include those in which nanoparticles having a eutectic structure are dispersed in the grain boundaries of the non-eutectic structure, and (e) those in which both the eutectic structure and the non-eutectic structure are nano-sized. Note that the through electrodes 12a and 12b formed using nanoparticles having a nanocomposite crystal structure also have a nanocomposite crystal structure.

  Further, in addition to the molten metal filling method, the liquid dispersion system in which the metal fine powder of the above-described metal material is dispersed in the liquid dispersion medium is filled in the vertical holes, and after the liquid dispersion medium is evaporated, the metal is processed by heat treatment. It is also possible to employ a method (liquid dispersion filling method) in which fine powder is melted with heat and cured while being pressed.

  The columnar heat sink 11 is provided in the thickness direction of the support substrate 1 and is distributed with a predetermined area occupancy with respect to the plate surface. A material suitable for the columnar heat sink 11 is a material having a low thermal resistance. The columnar heat sink 11 can also be formed of a metal body having a nanocomposite crystal structure using a molten metal filling method or a liquid dispersion filling method, like the through electrodes 12a and 12b. Although it does not limit, what added low melting metal materials, such as Sn, Ga, or In, to Al, Cu, Zn, etc. can be mentioned as a specific example. However, since the columnar heat sink 11 preferably has as low a thermal resistance as possible, the material, composition ratio, and the like need to be selected from such a viewpoint. In the present embodiment, the columnar heat sink 11 is a solid columnar body filled with contents, and has a circular cross section, but may have a square shape. Further, the columnar heat sink 11 is also covered with an electrical insulating layer 11a so that the columnar heat sink 11 is electrically insulated from the support substrate 1 which is a silicon layer.

  The columnar heat sink 11 penetrates in the thickness direction of the support substrate 1, is arranged in a matrix at a minute interval, and is connected to a heat radiator 6 provided on the back surface (other surface) of the support substrate 1. . Thereby, the columnar heat sink 11 can effectively release heat from the substrate 1.

  The support substrate 1 is a silicon layer, and a plurality of columnar heat sinks 11 are arranged around the light emitting element 3 so as to penetrate the silicon layer and are spaced from each other, and one end of each of the plurality of columnar heat sinks 11 is disposed. The silicon layer is connected in common to the radiator 6 provided on the other surface of the support substrate 1. According to this structure, a three-dimensional heat dissipation path is configured by the favorable heat dissipation characteristics of the silicon layer, and the heat dissipation characteristics of the entire lighting device can be improved. That is, the heat generated in the light emitting element 3 is collected by the silicon layer, transmitted from the silicon layer to the columnar heat sink 11, further transmitted from the columnar heat sink 11 to the other heat sink 11 through the silicon layer, and supported by the heat sink 11. The heat can be transmitted to the heat dissipating body 6 provided on the other surface of the substrate 1 and diffused and released from the heat dissipating body 6 toward the surface of the support substrate 1.

  The radiator 6 is made of a material having a relatively high thermal conductivity such as aluminum, and may be provided on the back surface of the support substrate 1 in a plurality of parts, or may be provided in common for all the heat sinks 3. You may provide as a single member connected. The form of the radiator 6 is not limited to the illustrated film shape, and may be a three-dimensional structure having an enlarged heat radiation area.

  The heat dissipation characteristics of the columnar heat sink 11 are basically determined by the thermal conductivity (or thermal resistance) of the composition material and the occupation ratio of the entire columnar heat sink 11 with respect to the plane area of the support substrate 1. Determined. For example, when a material with low thermal resistance is used as the columnar heat sink 11, the occupation ratio is reduced, and when a material with high thermal resistance is used, the occupation ratio is increased. That is, the occupation ratio of the columnar heat sink 11 is determined in consideration of the thermal conductivity of the composition material. On the other hand, when the occupation ratio is limited, a material having a suitable thermal conductivity is selected in consideration of the required heat dissipation characteristics.

  4 and 5 show details of the light-emitting element 3. The light emitting element 3 is a light emitting diode, and may be any of a white light emitting element, a red light emitting element, a green light emitting element, a blue light emitting element, and an orange light emitting element. The height position of the light emitting surface 3a of the light emitting element 3 is lower than the height position of the surface of the support substrate 1, and the fluorescent layer 5 is filled so as to fill the step between the two.

  The light emitting element 3 includes a transparent crystal layer 32, and a semiconductor stacked structure 31 in which a P-type semiconductor layer 311 and an N-type semiconductor layer 313 are stacked. Further, an active layer 312 is provided between the P-type semiconductor layer 311 and the N-type semiconductor layer 313.

  The transparent crystal layer 32 is typically sapphire, and one surface thereof becomes the light emitting surface 3a. When a transparent optical component (not shown) having a fine concavo-convex shape is arranged on the light emitting surface 3a, light can be diffused or dispersed on the light emitting surface 3a to achieve uniform surface light emission. Instead of providing the transparent optical component, a fine uneven shape may be formed on the light emitting surface 3a itself.

  On the other hand, a buffer layer (not shown) is provided on the surface opposite to the light emitting surface 3a, and the semiconductor multilayer structure 31 is grown on the transparent crystal layer 32 through the buffer layer. The semiconductor stacked structure 31 is typically a III-V group compound semiconductor, but is not limited to this, and other compound semiconductors having a PN junction can also be adopted.

  The N-type semiconductor layer 313 located on the transparent crystal layer 32 side has a portion 314 that does not overlap with the P-type semiconductor layer 311, and the N-side electrode 30 a is provided on the surface of the portion 314 that does not overlap. . On the other hand, the P-side electrode 30b is provided on the surface of the P-type semiconductor layer 311 in the overlapping portion. The N-side electrode 30a is not limited to a circular shape, and may be a square shape.

  In the present embodiment, the plane area of the N-side electrode 30a provided in the non-overlapping portion 314 is smaller than the plane area of the P-side electrode 30b provided in the overlapping portion. More specifically, regarding the electrode width as viewed in the arrangement direction of the N-side electrode 30a and the P-side electrode 30b, the electrode width of the N-side electrode 30a is smaller than the electrode width of the P-side electrode 30b. According to such an electrode arrangement, since the width of the non-overlapping portion 314 can be reduced and the width and area of the overlapping portion serving as the light emitting region can be reflectively increased, the amount of light emission can be increased.

  As shown in FIGS. 2 and 3, in the light emitting element 3, the P-side electrode 30 b of the P-type semiconductor layer 311 is connected to one end of one through-electrode 12 b in the recess 10, and the N-type semiconductor layer 313 has N The side electrode 30a is connected to one end of the other through electrode 21a. The P-side electrode 30b and the N-side electrode 30a are opposed to each other with an interval therebetween. In joining the P-side electrode 30b and the through-electrode 12b and joining the N-side electrode 30a and the through-electrode 12a, a joining film is interposed at the joining interface between them. The bonding film includes at least one low melting point metal component selected from the group of Sn, In, Bi, Ga, or Sb, Cr, Ag, Cu, Au, Pt, Pd, Ni, Ni—P alloy, It consists of a refractory metal material containing at least one selected from the group of Ni-B alloys. The low melting point metal is consumed by reacting with the P-side electrode 30b and the through-electrode 12b, the N-side electrode 30a and the through-electrode 12a to form an intermetallic compound, and the melting point is significantly increased after bonding.

  The light emitting element 3 in this embodiment shows an example applicable to the present invention, and is not limited to this. For example, the light-emitting element 3 may have a structure in which the vertical relationship between the transparent crystal layer 32 and the semiconductor multilayer structure 31 is reversed, and the electrode area is appropriately determined in consideration of current diffusion. is there.

  FIG. 7 shows another form of the light emitting device 2. The difference between the light emitting device of this embodiment and the embodiment described above is that the support substrate 1 is composed of three layers 1a to 1c and that the flat area of the recess 11 is expanded. .

  In this embodiment, the support substrate 1 is an SOI substrate, and a first silicon layer 1a constituting a first substrate layer, an oxide layer 1b constituting an insulating layer, and a second silicon layer constituting a second substrate layer. 1c is laminated in this order.

  As an SOI substrate, two types of substrates, a SIMOX (Separation by Implantation of Oxygen) method and a bonding method, are known depending on the manufacturing method, but any type of SOI substrate may be used. As a SIMOX SOI substrate, a technique is known in which oxygen molecules are implanted from the surface of a silicon crystal by ion implantation and oxidized with high heat to form an insulating layer of silicon oxide in the silicon crystal. Such an insulating layer is referred to as a buried oxide (BOX) layer.

  The concave portion 10 is formed by cutting out the surface of the second silicon layer 13, and the inner side surface thereof is an inclined surface whose opening area increases toward the opening end. The recess 10 has a plane area considerably larger than the plane area of the light emitting element 3, and the fluorescent layer 5 is filled between the outer periphery of the light emitting element 6 and the inner peripheral surface of the recess 10. Also, the reflective film 4 is attached to the inner wall surface of the recess 10 as in the previous embodiment.

  The through-electrodes 12a and 12b penetrate the first silicon layer 1a while being electrically insulated by the electrical insulation layers 13a and 13b, and the end portion on the recess 10 side has a connection portion 7 that penetrates the oxide layer 1b. Are connected to each other. The connection unit 7 is connected to both terminals 30 a and 30 b of the light emitting element 3. Similarly to the through electrodes 12a and 12b, the connecting portion 7 is preferably a metal body such as Cu formed by using the above-described molten metal filling method or liquid dispersion filling method. In addition, the shape of the connection part 7 is not restricted to a column shape, Other shapes, such as a square pole, can also be taken.

  The columnar heat sink 11 is provided so as to penetrate the first silicon layer 1 a in the thickness direction of the support substrate 1 and is connected to the radiator 6, similarly to the through electrodes 12 a and 12 b. That is, the columnar heat sink 11 is provided so as to extend from the back surface of the support substrate 1 to the boundary between the first silicon layer 1a and the oxide layer 1b. The columnar heat sink 11 can also be formed using the above-described molten metal filling method or liquid dispersion filling method. According to this configuration, in forming the columnar heat sink 11, the oxide layer 1b can function as an etching blocking layer. For this reason, since the depth dimension of the columnar heat sink 11 is defined by the layer thickness of the first silicon layer 1a, there is an advantage that the etching process management becomes extremely easy.

  As described above, the lighting device according to the present invention includes the support substrate 1, and the support substrate 1 includes a plurality of columnar heat sinks 11. Since the columnar heat sink 11 is provided in the thickness direction of the support substrate 1, heat generated by the light emitting operation of the light emitting element 3 is radiated to the outside of the support substrate 1 by the columnar heat sink 11, and the electrode 30 a of the light emitting element 3 is released. , 30b and the through-electrodes 12a, 12b can be preserved in junction strength, and the reliability of electrical connection can be maintained, and fluctuations in the light emission characteristics of the light-emitting element 3 due to heat generation can be avoided. You can also.

  The columnar heat sinks 11 are distributed with a predetermined area occupation ratio with respect to the plate surface of the support substrate 1. Accordingly, by appropriately selecting the thermal resistance of the material constituting the columnar heat sink 11 and the occupation ratio of the columnar heat sink 11, the heat generated by the light emitting operation of the light emitting element 3 is converted to the outside of the support substrate 1 by the column heat sink 11. Can efficiently dissipate heat. Furthermore, since one end of the columnar heat sink 11 is led out to the other surface side of the support substrate 1 and is connected to the heat radiator 6 provided on the other surface of the support substrate 1, the heat dissipation characteristics of the support substrate 1 are further improved. Can do.

  Furthermore, the support substrate 1 includes a first silicon layer 1a and a second silicon layer 1c, and a plurality of columnar heat sinks 11 penetrate the first silicon layer 1a and are spaced apart from each other around the light emitting element 3. One end of each of the plurality of columnar heat sinks 11 and the first silicon layer 1 a are connected in common to the heat dissipating body 6 provided on the other surface of the support substrate 1. According to this structure, a three-dimensional heat dissipation path is configured by the favorable heat dissipation characteristics of the silicon layer, and the heat dissipation characteristics of the entire lighting device can be improved. That is, the heat generated in the light emitting element 3 is collected by the first silicon layer 1a and the second silicon layer 1c, and transmitted to the columnar heat sink 11 from the first silicon layer 1a and the second silicon layer 1c. From the heat sink 11 to the heat sink 6 provided on the other surface of the support substrate 1, and from the heat sink 6 in the surface direction of the support substrate 1. It can be diffused and released to the outside.

  Since the space between the plurality of columnar heat sinks 11 is a silicon layer, the support substrate 1 has electrical conductivity. Therefore, the columnar heat sink 11 is covered with the electrical insulating layer 11 a so as to electrically insulate the columnar heat sink 11 from the support substrate 1.

  In the lighting device according to the present invention, the support substrate 1 includes a plurality of through electrodes 12a and 12b, and has a recess 10 on the plate surface. The through electrodes 12 a and 12 b penetrate the support substrate 1 in the thickness direction, and two through electrodes are disposed in each of the plurality of recesses 10 so that one end is exposed on the bottom surface of the recess 10. The light emitting element 3 is disposed in the recess 10 of the support substrate 1.

  The light emitting element 3 has a structure in which a P-type semiconductor layer 311 and an N-type semiconductor layer 313 are stacked on the other surface of the transparent crystal layer 32 opposite to the light emitting surface 3a. Then, inside the recess 10, the P-side electrode 30b of the P-type semiconductor layer 311 is connected to one end of one through electrode 12b, and the N-side electrode 30a of the N-type semiconductor layer 313 is connected to the other of the through electrodes 12a and 12b. Connected to one end.

  Therefore, the light emitting element 3 has a structure in which current is injected from the opposite side of the transparent crystal layer 32 in the stacking direction and the electrodes 30a and 30b of the light emitting element 3 do not appear on the light emitting surface 3a. It can be emitted to the outside. Further, the light generated in the semiconductor layer 31 is effectively guided to the light emitting surface 3 a of the transparent crystal layer 32 by suppressing the light scattering / absorption action in the transparent crystal layer 62 by the reflective film 4.

  Next, a liquid crystal display according to the present invention will be described with reference to FIG. The liquid crystal display includes a liquid crystal panel 8 and a backlight 9, and is conceptually not limited to a general computer display device or a liquid crystal display unit of a general-purpose electrical appliance, but may be a liquid crystal television, a mobile phone, a portable game machine, The present invention can also be applied to a portable electronic device such as a portable information terminal.

  The liquid crystal panel 8 is a liquid crystal module including a deflection filter, a glass substrate, a liquid crystal layer, and the like, and is driven by an electrical signal from a drive circuit (not shown) based on an image signal. The backlight 9 is the illuminating device shown in FIG. 8, and illuminates the liquid crystal panel 8 from the back side by the plurality of light emitting devices 2. But the form of the backlight 9 is not limited to this, For example, the illuminating device shown by FIG. 3 may be sufficient, and it cannot be overemphasized that any form of the illuminating device based on this invention can be taken.

  In the backlight 9, the through electrodes 12 a and 12 b are connected to a power supply unit via bump electrodes and a wiring board, and the light emitting element 3 to which power is supplied thereby irradiates the liquid crystal panel 8 with light. In addition, the columnar heat sink 11 is connected to the radiator 6 and discharges the heat inside the support substrate 1 to the back side of the liquid crystal display.

  Since the liquid crystal display according to the present invention includes the above-described illumination device, the above-described effects can be obtained.

  Next, a light emitting diode display according to the present invention will be described with reference to FIGS. Since the light emitting diode display uses the light emitting element itself as a pixel, it does not require a backlight and has an advantage that power consumption can be reduced.

  FIG. 10 shows a pixel 20 of the light-emitting diode display in plan view, while FIG. 11 shows a light-emitting diode display in which the pixels 20 are arranged in a matrix on the support substrate 1.

  One pixel 20 includes three light emitting devices 2 described above, and these light emitting devices 20 include a light emitting element 3R that emits red light, a light emitting element 3R that emits green light, and a light emitting element that emits blue light. Each has 3R. Since the light-emitting diode display according to the present embodiment is premised on full-color display, the light-emitting diodes 3R, 3G, and 3B have three colors as described above, but the present invention is not limited to this. For example, when it is assumed that only one color is displayed, the pixel 20 may be configured by any one of the three color light emitting elements 3R, 3G, and 3B. That is, the pixel 20 is configured by appropriately selecting the light emitting device 2 having a light emitting element corresponding to the display function.

  Further, in the pixel 20 of this embodiment, as shown in the drawing, the three light emitting devices 2 are arranged at the positions of the vertices of the triangle, but the present invention is not limited to this, and the three color light emitting elements 3R, 3G. , 3B can be used in an appropriate arrangement mode.

  In the light emitting diode display according to the present invention, the through electrodes 12a and 12b of the light emitting elements 3R, 3G, and 3B are connected to a thin film transistor (TFT) or the like, whereby each pixel 20 emits light by a drive circuit based on an image signal. Be controlled. Further, the columnar heat sink 11 is connected to the heat radiating body 6 in the same manner as the configuration shown in FIG. 9, and discharges the heat inside the support substrate 1 to the back side of the display.

  Since the light-emitting diode display according to the present invention includes the same configuration as that of the above-described illumination device, the above-described effects can be obtained.

  The signal lamp according to the present invention is applied to, for example, a railway traffic signal or a traffic signal, and includes a plurality of light emitting devices 20 arranged as in the above-described light emitting diode display. 3R, 3G, 3B are provided.

  Since the signal lamp according to the present invention includes the same configuration as that of the lighting device described above, the above-described effects can be obtained.

  Although the contents of the present invention have been specifically described above with reference to the preferred embodiments, it is obvious that those skilled in the art can take various modifications based on the basic technical idea and teachings of the present invention. It is.

DESCRIPTION OF SYMBOLS 1 Support substrate 2 Light emitting device 3 Light emitting element 10 Recessed part 11 Columnar heat sink 12a, 12b Through electrode 20 Pixel 30a N side electrode 30b P side electrode 311 P type semiconductor layer 312 N type semiconductor layer

Claims (5)

A lighting device including a support substrate and a plurality of light emitting elements,
The support substrate is provided with a plurality of light emitting element installation regions on a plate surface, and includes a plurality of through electrodes and a plurality of columnar heat sinks,
The plurality of through electrodes are arranged in two so as to penetrate the support substrate in the thickness direction, and to expose one end of each of the plurality of light emitting element installation regions,
The plurality of columnar heat sinks are provided in the thickness direction of the support substrate,
Each of the plurality of light-emitting elements includes a structure in which a P-type semiconductor layer and an N-type semiconductor layer are stacked, and is disposed in the light-emitting element installation region of the support substrate. Connected to one end of the through electrode, and the N-side electrode of the N-type semiconductor layer is connected to the other end of the through electrode,
Further, the support substrate includes a silicon layer,
The plurality of columnar heat sinks penetrates the silicon layer and is arranged around the light emitting element at a distance from each other, and is separated from the support substrate by an electrical insulating layer provided between the support substrate and the plurality of columnar heat sinks. Is electrically insulated,
One end of each of the plurality of columnar heat sinks is commonly connected to a heat radiator provided on the other surface of the support substrate.
Lighting device.   The lighting device according to claim 1, wherein the through electrode is electrically insulated from the support substrate. A liquid crystal display including a liquid crystal panel and a backlight,
The backlight is an illumination device according to claim 1 or 2, and illuminates the liquid crystal panel from the back.
LCD display. A light-emitting diode display including a support substrate and a plurality of light-emitting elements,
The support substrate is provided with a plurality of light emitting element installation regions on a plate surface, and includes a plurality of through electrodes and a plurality of columnar heat sinks,
The plurality of through electrodes are arranged in two so as to penetrate the support substrate in the thickness direction, and to expose one end of each of the plurality of light emitting element installation regions,
The plurality of columnar heat sinks are provided in the thickness direction of the support substrate,
Each of the plurality of light-emitting elements includes a structure in which a P-type semiconductor layer and an N-type semiconductor layer are stacked, and is disposed in the light-emitting element installation region of the support substrate. Connected to one end of the through electrode, and the N-side electrode of the N-type semiconductor layer is connected to the other end of the through electrode,
Further, the support substrate includes a silicon layer,
The plurality of columnar heat sinks penetrates the silicon layer and is arranged around the light emitting element at a distance from each other, and is separated from the support substrate by an electrical insulating layer provided between the support substrate and the plurality of columnar heat sinks. Is electrically insulated,
One end of each of the plurality of columnar heat sinks is a light emitting diode display commonly connected to a heat radiator provided on the other surface of the support substrate. A signal lamp including a support substrate and a plurality of light emitting elements,
The support substrate is provided with a plurality of light emitting element installation regions on a plate surface, and includes a plurality of through electrodes and a plurality of columnar heat sinks,
The plurality of through electrodes are arranged in two so as to penetrate the support substrate in the thickness direction, and to expose one end of each of the plurality of light emitting element installation regions,
The plurality of columnar heat sinks are provided in the thickness direction of the support substrate,
Each of the plurality of light-emitting elements includes a structure in which a P-type semiconductor layer and an N-type semiconductor layer are stacked, and is disposed in the light-emitting element installation region of the support substrate. Connected to one end of the through electrode, and the N-side electrode of the N-type semiconductor layer is connected to the other end of the through electrode,
Further, the support substrate includes a silicon layer,
The plurality of columnar heat sinks penetrates the silicon layer, and is arranged around the light emitting element at a distance from each other, and is electrically insulated from the support substrate by an electrical insulation layer provided between the support substrate and the plurality of column heat sinks. Has been
One end of each of the plurality of columnar heat sinks is commonly connected to a heat radiator provided on the other surface of the support substrate.
Signal light.

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