JP5010198B2 - Light emitting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inexpensive light-emitting device that allows to separately, simultaneously, and highly accurately detect light emitted from each of plural kinds of LED chips having different light-emitting colors while achieving miniaturization. <P>SOLUTION: In the light-emitting device, a mounting substrate 2 has each projector 2c internally projected from the tip of each wall 2b, and each projector 2c is provided with each of a plurality of light detecting elements 4 for separately detecting light emitted from each of the LED chips 1a-1d respectively having each light-emitting color. The mounting substrate 2 is composed so as to provide each light shield 39 that partitions an internal space surrounded by an LED mounting substrate 20 of a base substrate and the walls 2b, into each storage space for each of the LED chips 1a-1d respectively having each light-emitting color, in order to prevent the light respectively emitted from each of the LED chips 1a-1d from entering into light-receiving faces of two or more light detecting elements 4. <P>COPYRIGHT: (C)2008,JPO&amp;INPIT

Description

  The present invention relates to a light emitting device including a plurality of types of LED chips having different emission colors and a plurality of light detection elements that individually detect light emitted from the LED chips of each emission color.

  Conventionally, a plurality of types of LED chips having different emission colors (for example, a red LED chip, a green LED chip, and a blue LED chip), a plurality of drive circuits for supplying a drive current to each LED chip, and each LED chip Photodetection element (photosensor) composed of a photoelectric conversion element that photoelectrically converts a part of the emitted light, and a drive that is supplied from each drive circuit to each LED chip so that the output of the photodetection element is maintained at a reference value And a control circuit that feedback-controls the current so that mixed light (for example, white light) having a desired light color and color temperature can be obtained regardless of differences in temperature characteristics and lifetime characteristics of the LED chips for each emission color. A display device has been proposed (see, for example, Patent Document 1).

Here, in Patent Document 1, as shown in FIG. 6, there are a plurality of LED chips 100 having different emission colors and a base substrate portion on which the plurality of LED chips 100 are mounted on one surface side. A base substrate 221 and a light diffusing plate 230 in which a wall portion surrounding each LED chip 100 is formed on the one surface side of the base substrate 221 and light emitted from each LED chip 100 to the side is disposed to face the base substrate 221. A light-emitting device is disclosed that includes a reflection frame 222 that reflects to the side, and a photodetecting element 400 that is a photodiode disposed on the inner surface of the reflection frame 222.
Japanese Patent Laid-Open No. 10-49074 (paragraph [0025] and FIG. 11)

  By the way, the light emitting device having the configuration shown in FIG. 6 can be downsized as compared with the configuration in which the light detection element 400 is arranged in parallel with the LED chip 100 on the one surface of the base substrate 221, and the mounting area on the circuit board or the like can be reduced. Although the light can be reduced, the light emitted from each LED chip 100 is incident on the light receiving surface of the light detection element 400, so that the light emitted from each LED chip 100 of each emission color can be detected separately and simultaneously with high accuracy. I couldn't. Although it is possible to provide a filter that selectively transmits the light emission color of each LED chip 100 on the light receiving surface side of the light detection element 400, it is necessary to form or prepare a filter according to the light emission color of each LED chip 100. This increases the cost of manufacturing and management costs. In particular, when manufacturing multiple types of light emitting devices with different combinations of light emitting colors of the LED chip 100, the cost of each type of light emitting device is increased. It becomes the cause of.

  In the light emitting device having the configuration shown in FIG. 6, disturbance light is incident on the light receiving surface of the light detecting element 400 through the light diffusing plate 230, and the S / N ratio is lowered.

  The present invention has been made in view of the above-mentioned reasons, and its object is to detect light emitted from each of a plurality of types of LED chips having different emission colors with high accuracy while simultaneously reducing the size. It is another object of the present invention to provide a light emitting device that can reduce the cost.

  The invention of claim 1 is a mounting having a plurality of types of LED chips having different emission colors, a base substrate portion on which each LED chip is mounted, and a wall portion protruding from the base substrate portion so as to surround each LED chip. A mounting board having a projecting portion projecting inwardly from the tip of the wall portion, and a plurality of each detecting light emitted from each LED chip of each emission color in the projecting portion. The light detection element is provided, and the internal space surrounded by the base substrate portion and the wall portion is divided into storage spaces for the respective LED chips of the respective emission colors, and light emitted from each of the LED chips is two or more lights. It is characterized in that a light-shielding portion for preventing the light from entering the light-receiving surface of the detection element is provided.

  According to the present invention, the mounting substrate has the protruding portion that protrudes inward from the tip portion of the wall portion, and a plurality of light beams that are detected individually from the LED chips of the respective emission colors in the protruding portion. Therefore, it is possible to reduce the size compared to the case where a plurality of types of LED chips and a plurality of light detection elements are arranged on the same plane, and the base substrate portion and the wall portion surround the light detection device. The internal space is divided into storage spaces for the respective LED chips of the respective emission colors, and a light shielding portion is provided for preventing light emitted from each of the LED chips from entering the light receiving surfaces of two or more light detection elements. Therefore, the LED chips of the respective emission colors and the respective light detection elements can be made to correspond one-to-one, and the light emitted from the LED chips of the respective emission colors can be accurately detected by the corresponding light detection elements. And each light No need to leave providing different filter transmittance characteristics to each element, thus making it possible to lower costs.

  According to a second aspect of the present invention, in the first aspect of the present invention, the light shielding portion includes a partition wall that protrudes from the base substrate portion and divides the internal space into the storage spaces.

  According to this invention, the radiation range of the light radiated | emitted from each said LED chip can be restrict | limited by the light-shielding part.

  According to the first aspect of the present invention, the light emitted from each of a plurality of types of LED chips having different emission colors can be detected separately and accurately with a reduction in size, and the cost can be reduced. There is an effect.

(Embodiment 1)
Hereinafter, the light emitting device of the present embodiment will be described with reference to FIGS.

  In the light emitting device of this embodiment, a plurality of types of LED chips 1a, 1b, 1c, and 1d having different emission colors and a storage recess 2a that stores the LED chips 1a to 1d are formed on one surface, and the storage recess 2a. A mounting substrate 2 in which the LED chips 1a to 1d are mounted on the inner bottom surface thereof, and a translucent member 3 fixed to the mounting substrate 2 so as to close the housing recess 2a on the one surface side of the mounting substrate 2. , A plurality (four in this case) of light detection elements 4 provided on the mounting substrate 2 for detecting light emitted from the LED chips 1a to 1d of the respective emission colors, and a housing recess 2a of the mounting substrate 2 Each of the LED chips 1a to 1d and the bonding wires 14 that are connected to the LED chips 1a to 1d, each of which is made of a translucent sealing resin (for example, silicone resin, acrylic resin, etc.) filled in It is provided with a part 5. Here, the mounting substrate 2 has a hook-like protruding portion 2c protruding inward from the peripheral portion of the housing recess 2a on the one surface side, and each light detection element 4 is provided in the protruding portion 2c. Is provided. In the present embodiment, the package is constituted by the mounting substrate 2 and the translucent member 3, but the translucent member 3 is not necessarily provided, and may be appropriately provided as necessary.

  Here, in this embodiment, red LED chips, green LED chips, blue LED chips, and yellow LED chips are employed as the LED chips 1a, 1b, 1c, and 1d, respectively, and red light, green light, and blue light are used. White light can be obtained as a mixed light of yellow light and yellow light. However, the emission colors of the LED chips 1a to 1d are not particularly limited, and may be appropriately selected according to desired mixed color light.

  The mounting substrate 2 includes a rectangular plate-shaped LED mounting substrate 20 on which each LED chip 1a to 1d is mounted on one surface side, and a circular light extraction window disposed to face the one surface side of the LED mounting substrate 20 41 is formed, and a light detection element forming substrate 40 on which each light detection element 4 is formed, and a rectangular shape that is interposed between the LED mounting substrate 20 and the light detection element formation substrate 40 and communicates with the light extraction window 41. A space surrounded by the LED mounting substrate 20, the intermediate layer substrate 30, and the light detection element forming substrate 40 constitutes the housing recess 2a. is doing. Here, the outer peripheral shapes of the LED mounting substrate 20, the intermediate layer substrate 30, and the light detection element formation substrate 40 are rectangular, and the intermediate layer substrate 30 and the light detection element formation substrate 40 have the same outer dimensions as the LED mounting substrate 20. Is formed. Further, the thickness dimension of the light detection element forming substrate 40 is set smaller than the thickness dimension of the LED mounting substrate 20 and the intermediate layer substrate 30. In the present embodiment, the LED mounting substrate 20 constitutes a base substrate portion on which the LED chips 1a to 1d are mounted, and the intermediate layer substrate 30 and the light detection element formation substrate 40 constitute the LED chips 1a to 1d. A wall portion 2b that protrudes from the base substrate portion so as to surround 1d is configured, and a portion of the light detection element forming substrate 40 that protrudes above the opening window 31 of the intermediate layer substrate 30 is formed from the front end portion of the wall portion 2b. The overhang | projection part 2c which protrudes toward the direction is comprised.

  The LED mounting substrate 20, the intermediate layer substrate 30, and the light detection element formation substrate 40 described above are formed using silicon substrates 20 a, 30 a, and 40 a each having an n-type conductivity and a (100) plane main surface. In addition, the inner side surface of the intermediate layer substrate 30 is configured by a (111) plane formed by anisotropic etching using an alkaline solution (for example, TMAH solution, KOH solution, etc.) (that is, the intermediate layer substrate) 30, the opening area of the opening window 31 gradually increases as the distance from the LED mounting substrate 20 increases.) Light emitted from the LED chips 1 a to 1 d to the side (wall portion 2 b side) is forward (projected). This constitutes a mirror 2d that reflects to the part 2c side). In short, in the present embodiment, the intermediate layer substrate 30 also serves as a frame-like reflector that reflects light emitted from the LED chips 1a to 1d to the side.

  The LED mounting substrate 20 has two conductor patterns 25a that are electrically connected to the electrodes of the LED chips 1a to 1d on one surface side (the upper surface side in FIG. 1A) of the silicon substrate 20a. , 25a are formed, and a pair of conductor patterns 25b, 25b that are electrically connected to the photodetecting element 4 through two through-hole wirings 34, 34 formed in the intermediate layer substrate 30. Are formed, and each external connection electrode 27a, 27a, 27b formed on the other surface side (the lower surface side in FIG. 1A) of each conductor pattern 25a, 25a, 25b, 25b and the silicon substrate 20a. 27b are electrically connected to each other through the through-hole wiring 24. The LED mounting substrate 20 is also formed with a bonding metal layer 29 for bonding to the intermediate layer substrate 30 on the one surface side of the silicon substrate 20a.

  The LED chips 1a to 1d in the present embodiment are visible light LED chips in which a conductive substrate is used as a crystal growth substrate and electrodes (not shown) are formed on both surfaces in the thickness direction. Therefore, the LED mounting substrate 20 is formed by connecting one of the two conductor patterns 25a and 25a to which the LED chips 1a to 1d are electrically connected to the LED chip 1a to 1d. The die pad portion 25aa has a shape, and a lead-out wiring portion 25ab that is continuously formed integrally with the die pad portion 25aa and serves as a connection portion with the through-hole wiring 24. In short, the LED chips 1a to 1d are die-bonded to the die pad portion 25aa of the one conductor pattern 25a, and the electrodes on the die pad portion 25aa side are joined and electrically connected to the die pad portion 25aa, and the light extraction surface side The electrode is electrically connected to the other conductor pattern 25a through the bonding wire.

  Further, the LED mounting substrate 20 has a rectangular heat dissipation pad portion 28 made of a metal material having a higher thermal conductivity than the silicon substrate 20a in the projection region of each die pad portion 25aa on the other surface side of the silicon substrate 20a. The die pad portion 25aa and the heat dissipation pad portion 28 that overlap in the thickness direction of the silicon substrate 20a are formed of a plurality of cylindrical shapes made of a metal material (for example, Cu) having a higher thermal conductivity than the silicon substrate 20a. The thermal vias 26 are thermally coupled to each other, and the heat generated in the LED chips 1a to 1d is radiated through the thermal vias 26 and the heat radiation pad portions 28.

  By the way, the LED mounting substrate 20 has a plurality of through holes 22a in which each of the above-described through-hole wirings 24 is formed inside and a plurality of each of the above-described thermal vias 26 are formed in the silicon substrate 20a. A through hole 22b is provided in the thickness direction, and an insulating film 23 made of a thermal oxide film (silicon oxide film) is formed across the one surface and the other surface of the silicon substrate 20a and the inner surfaces of the through holes 22a and 22b. The conductor patterns 25a, 25a, 25b, and 25b, the bonding metal layer 29, the external connection electrodes 27a, 27a, 27b, and 27b, the heat dissipation pad portions 28, the through-hole wirings 24, and the thermal elements are formed. The via 26 is electrically insulated from the silicon substrate 20a.

  Here, each conductor pattern 25a, 25a, 25b, 25b, bonding metal layer 29, each external connection electrode 27a, 27a, 27b, 27b, and each heat radiation pad portion 28 are formed on the insulating film 23. It is composed of a laminated film of a film and an Au film formed on the Ti film, and is formed at the same time. In this embodiment, the thickness of the Ti film on the insulating film 23 is set to 15 to 50 nm, and the thickness of the Au film on the Ti film is set to 500 nm. However, these numerical values are only examples and are particularly limited. Not what you want. Further, the material of each Au film is not limited to pure gold, and may be one added with impurities. In addition, although a Ti film is interposed as an adhesion layer for improving adhesion between each Au film and the insulating film 23, the material of the adhesion layer is not limited to Ti, for example, Cr, Nb, Zr, TiN, TaN or the like may be used. Moreover, although Cu is adopted as the material of the through-hole wiring 24 and the thermal via 26, it is not limited to Cu, and for example, Ni may be adopted.

  Two intermediate layer substrates 30 are joined to and electrically connected to the two conductor patterns 25b and 25b of the LED mounting substrate 20 on one surface side (the lower surface side in FIG. 1A) of the silicon substrate 30a. Four sets of conductor patterns (not shown) are formed, and a bonding metal layer 36 to be bonded to the bonding metal layer 29 of the LED mounting substrate 20 is formed. Further, the intermediate layer substrate 30 is electrically connected to the other surface side of the silicon substrate 30a (upper surface side in FIG. 1 (a)) through the through-hole wirings 34, 34, and a pair of conductor patterns on the one surface side. Four sets of two conductor patterns 37, 37 that are connected to each other are formed, and a bonding metal layer 38 for bonding to the light detection element forming substrate 40 is formed.

  In addition, the intermediate layer substrate 30 has a plurality of through holes 32 formed therein in the thickness direction of the silicon substrate 30a, and the one surface of the silicon substrate 30a and the other. An insulating film 33 made of a thermal oxide film (silicon oxide film) is formed across the surface and the inner surface of each through hole 32, and each conductor pattern on the one surface side and each conductor pattern 37 on the other surface side, 37 and each of the bonding metal layers 36 and 38 are electrically insulated from the silicon substrate 30a. Here, the conductor patterns on the one surface side, the conductor patterns 37 and 37 on the other surface side, and the bonding metal layers 36 and 38 are formed on the Ti film formed on the insulating film 33 and the Ti film, respectively. It is composed of a laminated film with the formed Au film and is formed at the same time. In this embodiment, the thickness of the Ti film on the insulating film 33 is set to 15 to 50 nm, and the thickness of the Au film on the Ti film is set to 500 nm. However, these numerical values are only examples and are particularly limited. Not what you want. Here, the material of each Au film is not limited to pure gold, and may be added with impurities. Further, although a Ti film is interposed as an adhesion improving layer for adhesion between each Au film and the insulating film 33, the material of the adhesion layer is not limited to Ti, for example, Cr, Nb, Zr, TiN, TaN or the like may be used. Moreover, although Cu is adopted as the material of the through-hole wiring 34, it is not limited to Cu, and for example, Ni may be adopted.

  The photodetecting element forming substrate 40 is bonded to and electrically connected to the two conductor patterns 37 and 37 of the intermediate layer substrate 30 on one surface side (the lower surface side in FIG. 1A) of the silicon substrate 40a. Four sets of conductor patterns 47a and 47b (see FIG. 3) are formed, and a bonding metal layer 48 bonded to the bonding metal layer 38 of the intermediate layer substrate 30 is formed. Here, each light detection element 4 is configured by a photodiode, and one conductor pattern 47a of the pair of conductor patterns 47a and 47b formed on the light detection element formation substrate 40 is the light detection element 4. Is electrically connected to the p-type region 4a of the photodiode, and the other conductor pattern 47b is electrically connected to the silicon substrate 40a constituting the n-type region 4b of the photodiode.

  Further, in the photodetecting element forming substrate 40, an insulating film 43 made of a silicon oxide film is formed on the one surface side of the silicon substrate 40a, and the insulating film 43 also serves as an antireflection film of the photodiode. In the photodetecting element forming substrate 40, the one conductor pattern 47a is electrically connected to the p-type region 43a through a first contact hole (not shown) formed in the insulating film 43, and the other conductor is formed. The pattern 47b is electrically connected to the n-type region 4b through a second contact hole (not shown) formed in the insulating film 43. Here, each of the conductor patterns 47a and 47b and the bonding metal layer 48 is composed of a laminated film of a Ti film formed on the insulating film 43 and an Au film formed on the Ti film, and is formed at the same time. It is. In this embodiment, the thickness of the Ti film on the insulating film 43 is set to 15 to 50 nm, and the thickness of the Au film on the Ti film is set to 500 nm. However, these numerical values are only examples and are particularly limited. Not what you want. Here, the material of each Au film is not limited to pure gold, and may be added with impurities. Further, although a Ti film is interposed as an adhesion improving layer for adhesion between each Au film and the insulating film 43, the material of the adhesion layer is not limited to Ti, for example, Cr, Nb, Zr, TiN, TaN or the like may be used.

  In forming the mounting substrate 2 described above, the silicon substrate 40a and the intermediate layer substrate 30 on which the respective light detection elements 4, the insulating film 43, the respective conductor patterns 47a and 47b, and the bonding metal layer 48 are formed are formed at a low temperature. After performing a first bonding step for bonding by a room temperature bonding method or the like capable of direct bonding, a polishing step for polishing the silicon substrate 40a to a desired thickness is performed, and then an inductively coupled plasma (ICP) type dry etching apparatus After completing the light extraction window forming step of forming the light extraction window 41 on the silicon substrate 40a using the above, the light detection element formation substrate 40 is completed, and then the LED chips 1a to 1d are mounted and the bonding wires 14 are connected. What is necessary is just to perform the 2nd joining process which joins the board | substrate 20 for LED mounting and intermediate | middle layer board | substrate 30 by which normal temperature joining was performed. In the normal temperature bonding method, the bonding surfaces are contacted with each other after the bonding surfaces are cleaned and activated by irradiating the bonding surfaces with argon plasma, ion beam or atomic beam in vacuum before bonding. And bond directly at room temperature.

  In the first bonding step, the bonding metal layer 48 of the silicon substrate 40a and the bonding metal layer 38 of the intermediate layer substrate 30 are bonded, and the conductor patterns 47a and 47b of the silicon substrate 40a and the intermediate layer substrate 30 are bonded. The conductor patterns 37 and 37 are joined and electrically connected. Here, since the joint portions of the conductor patterns 47a and 47b and the conductor patterns 37 and 37 are shifted from the region overlapping the through-hole wiring 34, the joint surfaces of the conductor patterns 47a and 47b and the conductor patterns 37 and 37 are mutually connected. The flatness of the substrate can be increased, the junction yield can be increased, and the junction reliability can be increased. In the second bonding step, the bonding metal layer 29 of the LED mounting substrate 20 and the bonding metal layer 36 of the intermediate layer substrate 30 are bonded, and the conductor patterns 25b and 25b of the LED mounting substrate 20 The conductor patterns 35 and 35 of the intermediate layer substrate 30 are joined and electrically connected. Here, since the joint portions of the conductor patterns 25b and 25b and the conductor patterns 35 and 35 are shifted from the region overlapping the through-hole wiring 24 and the region overlapping the through-hole wiring 34, the conductor patterns 25b and 25b and the conductor pattern 35 are arranged. , 35, the flatness of the mutual joint surfaces can be increased, the joint yield can be increased, and the joint reliability can be enhanced.

  Moreover, the above-mentioned translucent member 3 is formed using the translucent board | substrate which consists of translucent materials (for example, silicone, an acrylic resin, glass, etc.). Here, the translucent member 3 is formed in a rectangular plate shape having the same outer peripheral shape as the mounting substrate 2, and light emitted from the LED chips 1 a to 1 d on the light extraction surface opposite to the mounting substrate 2 side. A fine concavo-convex structure that suppresses total reflection is formed. Here, the fine concavo-convex structure formed on the light extraction surface of the translucent member 3 is formed such that many fine concave portions have a two-dimensional periodic structure. The fine concavo-convex structure described above may be formed using, for example, a laser processing technique, an etching technique, an imprint lithography technique, or the like.

  In manufacturing the light emitting device of this embodiment, a silicon wafer capable of forming a large number of LED mounting substrates 20, intermediate layer substrates 30, and light detection element formation substrates 40 is used as each of the silicon substrates 20a, 30a, and 40a described above. In addition, a wafer-like one (translucent wafer) capable of forming a large number of translucent members 3 is used as the above-described translucent substrate, and the above-described first bonding step, polishing step, second bonding step, light The mounting substrate after the extraction window forming step, the second bonding step, the sealing portion forming step of filling the housing recess 2a of the mounting substrate 2 with the sealing resin to form the sealing portion 5, and the sealing portion forming step The wafer level package structure is formed by performing each process such as a third joining process for joining 2 and the translucent member 3 at the wafer level, and then divided into the size of the mounting substrate 2 by the dicing process. Yes. Therefore, the LED mounting substrate 20, the intermediate layer substrate 30, the light detection element forming substrate 40, and the translucent member 3 have the same outer size, so that a small package can be realized and manufacturing is facilitated. In addition, the relative positional accuracy between the mirror 2d in the intermediate layer substrate 30 and the light detecting element 4 in the light detecting element forming substrate 40 can be improved, and the light emitted from the LED chips 1a to 1d to the side is mirror 2d. And is guided to the light detection elements 4 corresponding to the LED chips 1a to 1d.

  By the way, as described above, the light emitting device according to the present embodiment is provided with the four light detecting elements 4 that individually detect the light emitted from the LED chips 1a to 1d of the respective emission colors on the light detecting element forming substrate 40. In order to associate the four light detection elements 4 with the four LED chips 1a to 1d having different emission colors on a one-to-one basis, the LED mounting substrate 20 that is the base substrate portion and the wall portion 2b The enclosed internal space (that is, the internal space of the storage recess 2a in the mounting substrate 2) is partitioned into the storage spaces of the LED chips 1a to 1d of the respective emission colors, and the light emitted from the LED chips 1a to 1d is emitted. A cross-shaped light shielding portion 39 that prevents the light incident on the light receiving surfaces of the two or more light detecting elements 4 is formed integrally with the intermediate layer substrate 30. In other words, in the light emitting device according to the present embodiment, the light shielding portion 39 is configured by a cross-shaped partition wall that protrudes from the LED mounting substrate 20 that is the base substrate portion and divides the internal space into the storage spaces. Has been. Here, in the light emitting device of the present embodiment, the opening window 31 of the intermediate layer substrate 30 is partitioned into four small spaces 31a by the light shielding portion 39, and the emission range of light emitted from each of the LED chips 1a to 1d. Is limited by the light shielding unit 39. Here, in this embodiment, the light shielding part 39 in the intermediate layer substrate 30 is formed simultaneously with the opening window 31 by anisotropic etching using an alkaline solution, and each side surface of the light shielding part 39 is within the opening window 31. Since it is a (111) surface like the side surface, each side surface of the light shielding portion 39 functions as a mirror that reflects light emitted from the LED chips 1a to 1d forward. In the light emitting device according to the present embodiment, the protruding height of the light shielding portion 39 from the LED mounting substrate 20 as the base substrate portion is lower than the protruding height of the wall portion 2b. Since the optical member 3 is separated, it is possible to prevent a shadow (dark part) from being generated due to the light shielding part 39.

  In the light emitting device of the present embodiment described above, the mounting substrate 2 has the overhanging portion 2c that protrudes inward from the tip end portion of the wall portion 2b, and four LED chips having different emission colors from each other in the overhanging portion 2c. Since the four light detection elements 4 for detecting the light emitted from the respective light beams 1a to 1d are provided, the four LED chips 1a to 1d and the four light detection elements 4 are arranged on the same plane. The size can be reduced compared to. Further, in the light emitting device of the present embodiment, since the light receiving surface of each photodetecting element 4 is on the LED mounting substrate 20 side in the overhanging portion 2c, disturbance light is incident on the light receiving surface of each photodetecting element 4. Therefore, the S / N ratio of the output of each photodetecting element 4 can be further increased.

  Furthermore, in the light emitting device according to the present embodiment, the internal space surrounded by the LED mounting substrate 20 as the base substrate portion and the wall portion 2b is partitioned into storage spaces for the respective LED chips 1a to 1d of the respective emission colors. Since the light-shielding part 39 which prevents the light radiated | emitted from each of 1a-1d from injecting into the light-receiving surface of two or more photodetectors 4 is provided, LED chip 1a-1d of each luminescent color and each light The detection elements 4 can be made to correspond to each other on a one-to-one basis, and only the light emitted from the corresponding LED chips 1a to 1d can be selectively detected in each light detection element 4. The light emitted from 1d can be detected with high precision by the corresponding light detection element 4, and it is not necessary to provide a filter with different transmission characteristics for each light detection element 4, so that the cost can be reduced. The ability. In the present embodiment, since the mounting substrate 2 is formed using a plurality of silicon substrates 20a, 30a, and 40a, the photodetecting element 4 composed of a photoelectric conversion element such as a photodiode is formed in a general semiconductor manufacturing process. As a result, it can be easily formed in the mounting substrate 2, and the cost can be reduced. Moreover, in this embodiment, since the room temperature bonding method in which direct bonding at a low temperature can be performed in each of the above-described bonding processes in forming the mounting substrate 2, the junction temperatures of the LED chips 1 a to 1 d in each bonding process. Can be prevented from exceeding the maximum junction temperature.

  Further, in the light emitting device of the present embodiment, since a plurality of thermal vias 26 are provided for each die pad portion 25aa where the LED chips 1a to 1d are die-bonded on the LED mounting substrate 20 of the mounting substrate 2, the LED chips 1a to The heat generated in 1d can be efficiently released to the outside, and the temperature rise of the junction temperature of the LED chips 1a to 1d can be suppressed, so that the input power to each of the LED chips 1a to 1d can be increased and the light output is high. Can be realized.

  Further, in the light emitting device of the present embodiment, the LED chips 1a to 1d mounted on the one surface side of the LED mounting substrate 20 are connected via the through-hole wiring 24 penetrating in the thickness direction of the LED mounting substrate 20. Thus, each photodetecting element 4 electrically connected to the external connection electrode 27a formed on the other surface side and formed on the photodetecting element forming substrate 40 is penetrated in the thickness direction of the intermediate layer substrate 30. The external connection electrode 27b formed on the other surface side of the LED mounting substrate 20 is electrically connected through the through-hole wiring 34 and the through-hole wiring 24 provided in the thickness direction of the LED mounting substrate 20. Since they are connected, they can be surface-mounted on a circuit board such as a printed circuit board, and the wirings are electrically connected to the LED chips 1a to 1d and the respective light detection elements 4 on one surface side of the mounting board 2. Pull As compared with the case of turning, downsizing of the mounting substrate 2.

  Further, when the lighting device is configured by mounting the light emitting device of the present embodiment on a circuit board or the like, for example, it is detected by the drive circuit unit that drives the LED chips 1 a to 1 d on the circuit board and the light detection elements 4. By providing a control circuit unit that feedback-controls the current flowing from the drive circuit unit to the LED chips 1a to 1d of the respective emission colors so that the light intensity to be maintained at the respective target values, each light detection element 4 is provided. Based on the respective outputs, the light outputs of the LED chips 1a to 1d of the respective emission colors can be individually controlled, and the colors are mixed regardless of the temporal changes in the light outputs of the LED chips 1a to 1d for the respective emission colors. The accuracy of the light color and color temperature of light (here, white light) can be improved. In short, desired mixed color light can be stably obtained.

(Embodiment 2)
Hereinafter, the light-emitting device of this embodiment will be described with reference to FIGS. 4 and 5.

  The basic configuration of the light emitting device of the present embodiment is substantially the same as that of the first embodiment, except that the light shielding portion 39 is formed of a material different from the silicon substrate 30a of the intermediate layer substrate 30. In addition, the same code | symbol is attached | subjected to the component similar to Embodiment 1, and description is abbreviate | omitted.

  In the present embodiment, the light shielding portion 39 is formed by forming a photosensitive resin layer made of a photosensitive resin (for example, SU8) in the opening window 31 of the intermediate layer substrate 30, and then forming the photosensitive resin layer by a photolithography technique. It is formed by patterning and depositing a metal film covering the exposed surface of the patterned photosensitive resin layer by, for example, sputtering.

  Thus, in the light emitting device according to the present embodiment, as in the first embodiment, the light emitted from each of the plurality of types of LED chips 1a to 1d having different emission colors can be individually and accurately accurately while reducing the size. In addition, the cost can be reduced.

The light-emitting device of Embodiment 1 is shown, (a) is a schematic sectional drawing, (b) is a principal part schematic plan view. It is a general | schematic disassembled perspective view of a light-emitting device same as the above. It is a schematic bottom view of the optical detection element formation board | substrate in the same as the above. 6 is a schematic cross-sectional view of a light emitting device according to Embodiment 2. FIG. It is a principal part schematic plan view of a light-emitting device same as the above. It is a schematic sectional drawing which shows a prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1a-1d LED chip 2 Mounting board 2b Wall part 2c Overhang | projection part 4 Photodetection element 20 Board | substrate for LED mounting (base board part)
39 Shading part (partition wall)

Claims (2)

  A plurality of types of LED chips having different emission colors, a base substrate portion on which each LED chip is mounted, and a mounting substrate having a wall portion protruding from the base substrate portion so as to surround each LED chip. Has a protruding portion that protrudes inward from the tip of the wall portion, and a plurality of light detecting elements that individually detect the light emitted from each LED chip of each emission color is provided in the protruding portion. The interior space surrounded by the base substrate portion and the wall portion is partitioned into storage spaces for each LED chip of each light emitting color, and light emitted from each LED chip is incident on the light receiving surfaces of two or more light detection elements A light-emitting device, characterized in that a light-shielding portion for preventing the light-emitting device is provided. The light-emitting device according to claim 1, wherein the light shielding portion includes a partition wall that protrudes from the base substrate portion and divides the internal space into the storage spaces.

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