JP2009224469A - Lighting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lighting device substantially improving a heat radiation property and preventing the luminance degradation of a light emitting element or the like. <P>SOLUTION: By using an insulating material whose heat radiation property is higher than that of polyimide or glass epoxy for the material of the substrate body 44 of a wiring substrate 43, even when the plurality of light emitting elements 13 are mounted highly densely on an element mounting substrate 12 and considerable heat is generated, the heat is radiated by the highly heat-radiating substrate body 44 of the wiring substrate 43. Thus, temperature rise is suppressed and the luminance degradation of the light emitting element or the like is prevented. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a lighting device.

Conventionally, as a multilayer wiring board, for example, a polyimide substrate as shown in Patent Documents 1, 2, and 3, or a glass epoxy substrate as shown in Patent Documents 4, 5, and 6, for example, is often used. Yes.
Japanese Patent Laid-Open No. 03-204994 Japanese Patent Laid-Open No. 04-162589 JP 05-175658 A JP 05-327224 A Japanese Patent Laid-Open No. 10-284842 Japanese Patent Laid-Open No. 11-330708

  By the way, a wiring board on which electrode wiring corresponding to each electrode portion of the plurality of light emitting elements is bonded to an element mounting board on which a plurality of light emitting elements (for example, LEDs) are mounted is configured as an illumination device. In this case, if a plurality of light emitting elements are mounted at a high density, considerable heat generation is expected, and the heat generation causes luminance degradation of the light emitting elements. In order to prevent such a situation, it is necessary to use a member with good heat dissipation in the lighting device, but conventionally, since a wiring board of the lighting device is generally made of polyimide or glass epoxy, There was a problem that the heat dissipation of the lighting device could not be sufficiently improved.

  An object of the present invention is to provide an illuminating device capable of remarkably improving heat dissipation and preventing luminance deterioration of a light emitting element.

In order to achieve the above object, according to the first aspect of the present invention, an element mounting substrate on which a plurality of light emitting elements are mounted, and electrode wiring corresponding to each electrode portion of the plurality of light emitting elements are formed on a substrate body. A plurality of wiring boards mounted on the element mounting board, wherein the surface opposite to the element mounting surface of the element mounting board and the surface on the electrode wiring extraction side of the wiring board are arranged to face each other. A lighting device in which each electrode portion of a light emitting element and an electrode wiring of a wiring board corresponding to each electrode portion of the plurality of light emitting elements are joined,
As a material of the substrate body of the wiring substrate, a material having insulating properties and higher heat dissipation than polyimide or glass epoxy is used.

  According to a second aspect of the present invention, in the illuminating device according to the first aspect of the present invention, the substrate body material of the wiring board is any one of SiC, AlN, and ceramics that have higher heat dissipation than polyimide or glass epoxy. It is characterized by being able to.

  According to a third aspect of the present invention, in the illumination device according to the first or second aspect, a heat dissipation via is formed in the element mounting board, and a heat dissipation of the element mounting board is formed in the wiring board. A heat dissipation via is formed at a position corresponding to the via formation position, and the heat dissipation via of the element mounting board is connected to the heat dissipation via of the wiring board.

  According to a fourth aspect of the present invention, in the illumination device according to any one of the first to third aspects, the electrode portions of the plurality of light emitting elements mounted on the element mounting substrate and the plurality of the plurality of light emitting elements are mounted. The electrode wiring of the wiring board corresponding to each electrode portion of the light emitting element is characterized by being joined by solder.

  According to a fifth aspect of the present invention, in the illumination device according to any one of the first to fourth aspects, the element mounting substrate further includes a through hole corresponding to each of the plurality of light emitting elements. And a phosphor filter plate disposed above the light emitting elements and in the through hole of the mold.

  According to a sixth aspect of the present invention, in the illumination device according to the fifth aspect, any one of Si, SiC, AlN, and ceramics is used for the element mounting substrate, and Si is used for the mold. It is characterized by that.

  According to a seventh aspect of the present invention, in the illumination device according to any one of the first to sixth aspects, the plurality of light emitting elements are configured as a dot matrix light source.

According to invention of Claim 1 thru | or 7, the element mounting board | substrate with which the some light emitting element is mounted, The wiring board in which the electrode wiring corresponding to each electrode part of the said several light emitting element is formed, Each electrode of a plurality of light-emitting elements mounted on the element mounting board, wherein the surface opposite to the element mounting surface of the element mounting board and the surface on the electrode wiring take-out side of the wiring board are opposed to each other. And an electrode wiring of a wiring board corresponding to each electrode portion of the plurality of light emitting elements,
As the substrate material of the wiring board, a material having insulating properties and higher heat dissipation than polyimide or glass epoxy is used, so that the heat dissipation of the lighting device can be remarkably improved. Luminance deterioration can be prevented.

  Particularly, according to the invention described in claim 3, in the lighting device according to claim 1 or 2, the element mounting board is formed with a heat dissipation via, and the wiring board includes the element mounting board. The heat radiation via is formed at a position corresponding to the position where the heat radiation via is formed, and the heat radiation via of the element mounting board is connected to the heat radiation via of the wiring board. Can be improved.

According to a fifth aspect of the present invention, in the illumination device according to any one of the first to fourth aspects, the element mounting substrate further corresponds to each of the plurality of light emitting elements. A mold having a through-hole formed therein and a phosphor filter plate disposed above the light-emitting elements and in the through-hole of the mold are provided to prevent uneven color and crosstalk. In addition, a plurality of light emitting elements can be mounted at a high density by reducing the interval between the light emitting elements, and the heat resistance and the heat dissipation effect can be further improved.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a diagram (plan view) illustrating a configuration example of a lighting device according to the present invention, and FIG. 2 is a cross-sectional view taken along line AA in FIG. 3 and 4 are diagrams for explaining each component of FIG. 1, 2, 3, and 4, 12 is an element mounting substrate, 13 is a plurality of light emitting elements, 14 a and 14 b are electrode portions of the plurality of light emitting elements 13, 15 is gold (Au), 16 Is a conducting portion (for example, copper (Cu) via) for conducting from the light emitting element 13 side of the element mounting substrate 12 to the electrode portions 14a and 14b on the side opposite to the light emitting element 13, and 17 is light emission of the element mounting substrate 12. A heat dissipation via for heat dissipation penetrating from the element 13 side to the side opposite to the light emitting element 13, 18 is a mold, 19 is a phosphor filter plate, 43 is a wiring substrate, 44 is a substrate of the wiring substrate 43 The main body, 45a and 45b are electrode wirings corresponding to the electrode portions 14a and 14b of the light emitting element 13, 46 is a heat dissipation via for heat dissipation, and 50 is solder.

  First, referring to FIG. 3, the lighting device includes an element mounting substrate 12 on which a plurality of light emitting elements 13 are mounted, and electrode wirings 45 a and 45 b corresponding to the electrode portions 14 a and 14 b of the plurality of light emitting elements 13. Has a wiring substrate 43 formed on the substrate body 44, and the surface on the side opposite to the element mounting surface of the element mounting substrate 12 and the surface on the electrode wiring take-out side of the wiring substrate 43 are arranged to face each other. ing.

  Then, referring to FIG. 4, the electrode portions 14 a and 14 b of the plurality of light emitting elements 13 mounted on the element mounting substrate 12 and the wiring substrate 43 corresponding to the electrode portions 14 a and 14 b of the plurality of light emitting elements 13. The electrode wirings 45a and 45b are joined by, for example, solder 50 or the like. In FIG. 2, the electrode portions 14 a and 14 b of the plurality of light emitting elements 13 mounted on the element mounting substrate 12 and the electrode wiring 45 a of the wiring substrate 43 corresponding to the electrode portions 14 a and 14 b of the plurality of light emitting elements 13 are shown. 45b are joined together with, for example, solder 50 or the like.

  In more detail, referring to FIG. 1, the plurality of light emitting elements 13 are two-dimensionally arranged in a matrix (2 × 4) in the example of FIG. As can be seen from the examples of FIGS. 2, 3, and 4, each light-emitting element 13 is flipped by Au bump 15 to a conductive portion (for example, copper (Cu) via) 16 through a bonding pad (not shown). Chip connected. Flip chip connection can reduce the area occupied by mounting compared to wire connection, and enables high-density mounting. Moreover, as each light emitting element 13, for example, a light emitting element having a light emitting layer made of a GaN-based material is used, and emits ultraviolet light, blue light, and green light. Or each light emitting element 13 is white LED etc., for example. In the example of FIG. 1, the number of light emitting elements is 2 × 4, but the number is appropriately selected according to the brightness required for the lighting device.

More specifically, in the example of FIGS. 1 to 4, the plurality of light emitting elements 13 are dot matrix light sources that can control light distribution independently and freely for each light emitting element 13. It has a structure that can be configured as a dot matrix LED light source using LEDs.

  The element mounting substrate 12 is, for example, a silicon (Si) substrate, and 0.1 mmφ through holes penetrating from the light emitting element 13 side of the element mounting substrate 12 to the side opposite to the light emitting element 13 are electrode portions 14a and 14b. A conductive portion (for example, a copper (Cu) via filled with copper (Cu) in the through hole) 16 is formed in the through hole by copper plating or the like. As a material for the element mounting substrate 12, in addition to silicon (Si), which is the above-described inorganic material, a SiC substrate, an AlN substrate, or ceramics such as alumina can also be used.

  The element mounting board 12 is provided with a heat dissipation via (for example, a copper (Cu) via) 17 for heat dissipation penetrating from the light emitting element 13 side of the element mounting board 12 to the side opposite to the light emitting element 13. .

  In addition, the wiring substrate 43 is generically referred to as electrode wiring (for example, wiring such as copper (Cu) or aluminum) 45a and 45b (hereinafter referred to as 45a and 45b) corresponding to the electrode portions 14a and 14b of the plurality of light emitting elements 13. 45) is formed on the substrate body 44. Here, the electrode portions 14 a and 14 b of the plurality of light emitting elements 13 mounted on the element mounting substrate 12 and the electrode wirings 45 a and 45 b of the wiring substrate 43 corresponding to the electrode portions 14 a and 14 b of the plurality of light emitting elements 13. Is joined by, for example, solder 50 and is electrically connected. More specifically, when a plurality of light emitting elements 13 is configured as a dot matrix light source, the wiring 45 is arranged in, for example, a row direction and a column direction, and each light emitting element 13 is selectively driven so that each light emitting element 13 can be selectively driven. Is electrically connected. That is, in this case, the wiring 45 is connected to each light emitting element 13 in a hierarchical structure as a dot matrix wiring as shown in FIGS.

  In addition, a heat dissipation via (for example, copper (Cu) via) 46 for heat dissipation is formed in the wiring board 43 at a position corresponding to the position where the heat dissipation via 17 of the element mounting board 12 is formed. The heat dissipation via 17 and the heat dissipation via 46 of the wiring board 43 are connected by, for example, solder 50.

  By the way, in this invention, the material of the board | substrate main body 44 of the wiring board 43 has an insulating property, and has higher heat dissipation than polyimide or glass epoxy. Specifically, for example, any one of SiC, AlN, and ceramics is used as a material having insulating properties and higher heat dissipation than polyimide or glass epoxy. Here, as the ceramic, for example, a low-temperature fired laminated ceramic (LTCC) is used.

  In the present invention, the material of the substrate main body 44 of the wiring substrate 43 is made of a material having insulating properties and higher heat dissipation than polyimide or glass epoxy. Even when a large amount of heat is mounted and a considerable amount of heat is generated, heat is dissipated by the substrate main body 44 of the wiring substrate 43 with high heat dissipation, thereby suppressing temperature rise and preventing luminance deterioration of the light emitting element. be able to. As described above, in the present invention, the material of the substrate main body 44 of the wiring substrate 43 is made of an insulating material that has a higher heat dissipation than polyimide or glass epoxy, thereby significantly improving the heat dissipation of the lighting device. Can be made.

  Furthermore, in the present invention, the element mounting substrate 12 has a heat dissipation via (for example, a copper (Cu) via) 17 for heat dissipation penetrating from the light emitting element 13 side of the element mounting substrate 12 to the side opposite to the light emitting element 13. Further, the wiring board 43 is provided with a heat radiation via (for example, copper (Cu) via) 46 for heat radiation at a position corresponding to the position where the heat radiation via 17 of the element mounting substrate 12 is formed. Since the heat dissipation vias 17 of the mounting substrate 12 and the heat dissipation vias 46 of the wiring substrate 43 are connected by, for example, solder 50, the heat generated from the plurality of light emitting elements 13 is generated by the heat dissipation vias 17 and the wiring substrate 43 of the element mounting substrate 12. The heat radiating via 46 is further radiated (and further radiated from the wiring board 43 having a high heat radiating property via the heat radiating via 46), and the heat radiating property of the lighting device can be further improved.

  As described above, the present invention is particularly useful when a plurality of light emitting elements 13 are mounted on the element mounting substrate 12 with high density and considerable heat generation is expected. Specifically, the plurality of light emitting elements 13 is configured as a dot matrix light source (a dot matrix LED light source using, for example, a white LED for each light emitting element 13) in which the plurality of light emitting elements 13 are mounted on the element mounting substrate 12 with high density. In some cases, the present invention is particularly useful.

  Hereinafter, a novel configuration of the present invention (which can be configured as a dot matrix light source, for example) capable of mounting a plurality of light emitting elements 13 on the element mounting substrate 12 with high density (specifically, a prior application of the present application by the applicant of the present application). The configuration described in Japanese Patent Application No. 2007-309482) will be described.

  Referring to FIGS. 1, 2, 3, and 4 again, the element mounting substrate 12 further includes a mold 18 in which a through hole corresponding to each of the plurality of light emitting elements 13 is formed, and each light emitting element 13. And a phosphor filter plate 19 disposed in a through hole of the mold 18.

  More specifically, a plurality of through holes (openings) 20 are formed in the mold 18 at positions corresponding to the respective light emitting elements 13 using a photolithography technique on a 0.3 mm thick silicon (Si) substrate, for example. Yes. If it sees in the whole silicon substrate, it will become the thing in which the grid | lattice formwork 18 was formed. Adjacent through holes (openings 20) are separated by a mold 18 that functions as a partition wall. For example, the mold 18 and the substrate 12 are bonded to the substrate 12 by providing the Au layer 15 at a position where the mold 18 and the substrate 12 face each other and applying heat, temperature and pressure. Each light emitting element 13 is housed in a through hole (opening) 20 of the mold 18 and is reliably separated by the mold 18 that functions as a partition wall. The mold 18 is formed of an inorganic material such as Si or a permanent resist.

  By manufacturing the mold 18 using a semiconductor process, the through holes (openings) 20 are formed in the mold 18 with high accuracy and high density. For example, the pitch of the through holes (openings) 20 can be manufactured at 100 μm or less. As a result, the interval between the light emitting elements 13 can be shortened, and a high-definition lighting device can be realized.

  Such a mold 18 is prepared separately by forming a through hole in the element mounting substrate 12 or forming a conductive portion (for example, a copper (Cu) via filled with copper (Cu)) 16, Furthermore, this is for facilitating polishing and cleaning of the substrate 12 after the copper (Cu) via 16 is formed (after copper plating). Furthermore, it is for making it easier to form bumps for joining the light emitting elements 13.

  Further, the phosphor filter plate 19 is disposed in the through hole (opening) 20 on the upper surface of each light emitting element 13. The phosphor filter plate 19 can be formed of an inorganic material using a glass sintered body in which YAG: Ce particles are dispersed even in a YAG: Ce polycrystalline substrate. As long as it is the upper surface of the light emitting element 13, the phosphor filter plate 19 may be in contact with the light emitting element 13 or may be spaced apart.

  Since the phosphor filter plate 19 is manufactured in advance according to the size of the through hole (opening) 20, the amount of the phosphor supplied to each light emitting element 13 can be controlled with high accuracy. For example, in the case where all the light emitting elements 13 arranged in a matrix form have the same light emission (for example, white light), the phosphor filter plates 19 are all made with the same thickness and the same size. On the other hand, the size and thickness of the phosphor filter plate 19 supplied to each light emitting element 13 can be changed according to the light emission characteristics required for the lighting device.

  According to such a configuration, the light emitting element 13 and the phosphor filter plate 19 are disposed in each through hole (opening) 20 formed in the mold 18, so that the adjacent light emitting element 13 and the phosphor filter plate 19 are arranged. Are reliably divided by the mold 18 functioning as a partition wall, and crosstalk between the light emitting elements 13 can be prevented. Thereby, each dot comprised by the light emitting element 13 and the fluorescent substance filter board 19 is formed as an independent light source.

  In addition, the phosphor filter plate 19 is formed with a predetermined thickness and is individually disposed in each through hole 20, so that the amount of the phosphor supplied to each light emitting element 13 can be accurately controlled, and light emission can be achieved. Color unevenness can be prevented.

  In addition, by manufacturing both the substrate 12 and the mold 18 by a semiconductor process, the lighting device according to the present invention can be made to have a higher definition than the conventional one. In addition, since all processes are performed in the state of a silicon wafer, the manufacturing process is highly productive and highly accurate. For example, the substrate of the lighting device is manufactured in a wafer state, and the light emitting element is mounted on the substrate. Next, through holes are formed in a wafer having the same shape as the substrate to form a mold, and the mold and the substrate are bonded together in a wafer state. By arranging a phosphor filter plate in each through-hole of the mold and dicing the mold and the substrate bonded together in a wafer state into an arbitrary size, the lighting device can be manufactured entirely by a semiconductor process.

  Moreover, the heat of the phosphor particles contained in the phosphor filter plate can be efficiently radiated from the mold by manufacturing the mold with a material having good heat dissipation such as silicon. Thereby, the problem of temperature quenching of the phosphor particles can also be solved.

  Since the illuminating device according to the present invention can selectively drive each light emitting element 13, for example, when the illuminating device is used as illumination for a vehicle, a headlamp capable of electronically controlling light distribution with high precision and high precision. And a light source for a rear lamp can be realized.

  As a light source for a headlamp, it is possible to obtain light distribution characteristics in which AFS and traveling / passing beam are controlled more than binary light distribution control. Also, as a light source for a rear lamp, for example, it is recognized as normal light by human eyes, but it can be used as a lighting device that can communicate between vehicles by lighting a specific light emitting element at a specific frequency. Is also possible.

FIG. 5 is a diagram showing a front luminance distribution along the line BB of the lighting device shown in FIG. In FIG. 5, the vertical axis represents luminance (cd / m ² ), and the horizontal axis represents the relative distance (mm) from the center of the lighting device to each light emitting element. As shown in FIG. 5, the luminance between adjacent light emitting elements is significantly lower than the luminance on the light emitting elements. This indicates that there is no light emission between the light emitting elements, that is, no crosstalk, and it can be understood that the adjacent light emitting elements and the phosphor filter body are reliably separated by the partition walls of the mold.

  As described above, according to the configurations of FIGS. 1, 2, 3, and 4, in an illumination device using a plurality of light emitting elements as light sources, it is possible to prevent color unevenness and crosstalk, and between the light emitting elements. Can be mounted at a high density, and the heat resistance and heat dissipation effect can be improved. Specifically, when each light emitting element 13 is configured as a white LED, and further, as a dot matrix LED light source that allows the light distribution to be freely controlled, it becomes possible to make the white LED without color unevenness, In addition, it is possible to configure the dots with high density and no crosstalk. In addition, when a large number of light emitting elements are arranged, a large amount of current is applied and a considerable amount of heat is generated. However, even when a large number of light emitting elements generate a considerable amount of heat, as described above, the material of the substrate body 44 of the wiring board 43 In addition, by using a material having insulating properties and higher heat dissipation than polyimide or glass epoxy, and further by providing heat dissipation vias 17 and 46, the heat dissipation of the lighting device is significantly improved, Temperature quenching of the phosphor due to heat generation and luminance deterioration of the LED can be prevented.

  Next, the specific manufacturing method of the illuminating device (for example, LED light source using white LED) of this invention is demonstrated.

  Specifically, when a Si substrate is used as the element mounting substrate 12, a through hole is formed in the Si substrate 12 using a so-called Cu wiring embedding technique, and Cu wiring (copper (Cu)) is formed to the back side of the Si substrate 12. Via) 16 is passed. Further, in the substrate 12, a heat dissipation via 17 for heat dissipation is formed in an outer portion of the Cu wiring (copper (Cu) via) 16. On the other hand, Si is etched on the Si substrate 12 by a microfabrication technique to form a mold 18 for each dot, and this mold 18 is heated and heated to form a substrate 12 on which through holes are formed. Join. Such a mold 18 is prepared separately, as described above, to facilitate the formation of through holes, the formation of Cu vias 16, and the polishing and cleaning of the substrate 12 after Cu plating. This is to make it easier to form bumps for LED bonding.

  On the other hand, when LTCC is used for the substrate body 44 of the wiring substrate 43, that is, when the wiring substrate 43 is an LTCC substrate, a solder pad is formed on the LTCC substrate 43 at a portion corresponding to the electrode portion of the LED. Further, below this pad, dot matrix wiring is connected to each LED chip in a hierarchical structure as shown in FIGS. Further, a heat radiating via 17 reaching the upper surface of the LTCC substrate 43 is formed in the peripheral portion of the Si substrate 12 on which the LED chip is mounted. FIG. 1 is a view as seen from above. The LED mounting substrate 12 is bonded to the LTCC substrate 43. Further, a heat radiating via 46 connected to the heat radiating via 17 of the Si substrate 12 is formed on the outer peripheral portion of the LTCC substrate 43. The LED light source is realized by using these substrates 12 and 43 in the following procedure.

  First, the Si mold 18 and the Si substrate 12 on which the vias 16 and 17 are formed are bonded using the Au—Au bonding 15. Next, the flip chip LED 13 is bonded to the Si substrate 12 with Au bumps. Further, a YAG: Ce phosphor filter plate 19 is placed on the upper surface of each chip 13. The phosphor filter plate 19 may be a YAG: Ce polycrystalline substrate or a glass sintered body in which YAG: Ce particles are dispersed.

  With such a configuration, since the partition 18 is formed of Si between the light emitting elements (LED chips) 13, each dot can be formed as an independent white light source. This dot interval can be formed at a high density up to about 100 μm by using a semiconductor process. The barrier ribs 18 are made of Si, and the phosphor filter plates 19 are formed on the individual LED chips 13 to form an independent white light source, so that a space for wire bonding is required, so that the density cannot be increased. And the problem of crosstalk of light with the adjacent dots can be solved, and a headlamp light source that electronically controls light distribution with high density can be realized. At the same time, since all processes can be performed in the state of Si wafer, the productivity is very good and the accuracy can be increased. The LED light source substrate 12 thus formed is bonded to the LTCC substrate 43 using solder bumps 50. By doing so, it is possible to realize an LED dot matrix light source excellent in heat dissipation.

  Next, an example is shown.

  In this embodiment, a hole is formed at a position corresponding to each dot by using a photolithography technique on a Si substrate having a thickness of 0.3 mm. When viewed from the whole Si wafer, the dot mold 18 is formed in a lattice shape. This may be chemical etching or RIE (reactive ion etching). This time, a 1.1 mm square hole was formed by RIE. The pitch in the BB direction of FIG. 1 is 1.2 mm, and the depth is 300 μm.

Next, two through holes each having a diameter of 0.1 mm were formed in another Si substrate 12. Then, holes for heat dissipation vias are formed around the substrate 12 at appropriate intervals. The diameter of the hole for the heat dissipation via is also 0.1 mmφ. A Cu via 17 was formed in the through hole by a Cu filling technique. As a process, after forming holes for heat dissipation vias, the entire Si substrate 12 is hydrothermally oxidized to form a SiO ₂ film 51 of about 200 nm on the substrate surface, and Cu plating is performed here to fill the through holes, Then, back surface polishing was performed. Next, pads for solder bumps were formed on the lower surfaces of these through holes by electroless plating. On the other hand, on the surface, Au is deposited after removing with photolithography using a resist to form Au on the part corresponding to the bonding pad and mold on the upper surface of these through holes, and then lift-off and flip A chip LED bonding pad and a formwork joint were formed. Next, Au was vapor-deposited on the back surface of the wafer on which the above-described mold 18 was formed, and the mold parts were superposed and Au-Au bonding was performed by applying ultrasonic waves at 200 ° C. The flip chip LED 13 was mounted on such a substrate by Au—Au bonding. On the LED chip 13 thus configured, a glass plate (phosphor filter plate) 19 having a thickness of 0.3 μm in which about 6% of YAG: Ce phosphor particles are dispersed is formed in accordance with each dot size. (See FIG. 6). A silicon resin or the like may be inserted between the LED chip and the phosphor filter plate 19 as necessary. At this time, irregularities may be formed on the surface of the phosphor filter 19. The roughness of the unevenness is about 1 μm-10 μm. By doing so, it is possible to realize a white automotive LED light source that is very simple and has accurate optical characteristics as intended. The phosphor filter plate 19 may be a YAG: Ce polycrystalline plate instead of glass in which YAG: Ce is dispersed. In this case as well, unevenness may be formed on one side. In order to join the LED mounting substrate formed in this way to the LTCC substrate, the surface of the LTCC substrate is not necessarily flat but has minute irregularities, and thus bonding is performed using solder bumps.

  In the LED light source of the dot matrix thus produced, the luminance distribution was taken in the LED array direction (the BB direction in FIG. 1) as shown in FIG. 5, and from FIG. 5, the Si mold 18 and the phosphor It can be seen that the light emission for each dot is neatly separated by using the filter 19.

  FIG. 7 shows the input current when the phosphor is dispersed in the resin and applied to the LED, and when the phosphor filter plate 19 formed by dispersing the phosphor in glass is placed on the light emitting element (LED). It is a figure which shows the result of having investigated the change of the brightness | luminance (light beam) with respect to. As can be seen from FIG. 7, it can be seen that the deterioration in luminance is improved in the high current region because the phosphor is dispersed in glass and formed into a plate shape so that the heat dissipation is superior. In the present invention, the phosphor filter plate 19 is fixed to the Si mold 18 having excellent thermal conductivity, and the heat dissipation via 17 is formed on the Si substrate 12, so that the heat from the light emitting element (LED) 13 is increased. Since the phosphor filter plate 19 is also joined to the Si mold 18 connected thereto, compared to the case where a conventional phosphor is dispersed in resin and applied to the LED. Thus, the temperature characteristics are greatly improved.

The present invention can be used for a white LED light source for automobiles, a multifunctional white LED light source for automobiles, and the like.

It is a figure (plan view) showing an example of composition of an illuminating device concerning the present invention. It is sectional drawing in the AA of FIG. It is a figure for demonstrating each component of FIG. It is a figure for demonstrating each component of FIG. It is a figure which shows the front luminance distribution in the BB line of FIG. It is a figure which shows the specific example of this invention. Luminance against luminous current (light flux) when phosphor is dispersed in resin and applied to LED and phosphor filter plate formed by dispersing phosphor in glass is placed on light emitting element (LED) It is a figure which shows the result of having investigated the change of ().

Explanation of symbols

12 Element mounting substrate 14a, 14b Electrode part of light emitting element 15 Gold (Au)
16 Conducting part (for example, copper (Cu) via)
17 Heat Dissipation Via 18 Form 19 Phosphor Filter Plate 43 Wiring Board 44 Wiring Substrate Main Body 45a, 45b Electrode Wiring 46 Heat Dissipation Via 50 Solder 51 Silicon Thermal Oxide Film (SiO ₂ Film)
52 Low melting point glass

Claims (7)

An element mounting surface of the element mounting board, comprising: an element mounting board on which a plurality of light emitting elements are mounted; and a wiring board on which an electrode wiring corresponding to each electrode portion of the plurality of light emitting elements is formed on the board body. The surface on the opposite side and the surface on the electrode wiring take-out side of the wiring board are arranged facing each other, and each electrode portion of the plurality of light emitting elements mounted on the element mounting substrate and each electrode portion of the plurality of light emitting elements A lighting device joined to the electrode wiring of the wiring board corresponding to
The lighting device according to claim 1, wherein a material of the substrate body of the wiring board is made of an insulating material having higher heat dissipation than polyimide or glass epoxy. 2. The lighting device according to claim 1, wherein any of SiC, AlN, and ceramics having higher heat dissipation than polyimide or glass epoxy is used as a material of a substrate body of the wiring board. In the lighting device according to claim 1 or 2, the element mounting board is formed with a heat dissipation via, and the wiring board is at a position corresponding to a position of the heat dissipation via of the element mounting board. A heat dissipation via is formed, and the heat dissipation via of the element mounting board is connected to the heat dissipation via of the wiring board. 4. The lighting device according to claim 1, wherein each electrode portion of the plurality of light emitting elements mounted on the element mounting substrate and wiring corresponding to each electrode portion of the plurality of light emitting elements is provided. A lighting device characterized in that the electrode wiring of the substrate is joined with solder. 5. The lighting device according to claim 1, wherein the element mounting substrate further includes a mold having a through-hole corresponding to each of the plurality of light emitting elements, and each of the plurality of light emitting elements. An illuminating device comprising a phosphor filter plate disposed above the light emitting element and disposed in the through hole of the mold. 6. The illumination device according to claim 5, wherein any one of Si, SiC, AlN, and ceramics is used for the element mounting substrate, and Si is used for the mold. 7. The lighting device according to claim 1, wherein the plurality of light emitting elements are configured as a dot matrix light source. 8.

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