JP4877239B2 - Method for manufacturing light emitting device - Google Patents

Description

  The present invention relates to a method for manufacturing a light emitting device using a light emitting diode chip (LED chip).

  Conventionally, an LED, a drive circuit unit that drives the LED, a light detection element that detects the light output of the LED, and an LED from the drive circuit unit so that the output of the light detection element is maintained at a preset target value. There has been proposed an illuminating device including a control circuit unit that feedback-controls a current flowing in the direction (for example, see Patent Document 1).

  Here, in Patent Document 1, as shown in FIG. 11, an inner bottom surface of a housing recess 102a in which a plurality of types of LEDs 101a, 101b, and 101c having different emission colors are formed on one surface of a mounting substrate (base member) 102. And a transparent resin layer 103 for sealing the LEDs 101a, 101b, and 101c is provided on the one surface side of the mounting substrate 102 so as to cover the LEDs 101a, 101b, and 101c. A light emitting device is disclosed in which a photodetection element forming substrate 106 on which photodetection elements 104a, 104b, and 104c made of photodiodes that detect light emitted from the LEDs 101a, 101b, and 101c are formed is disposed.

  In the light emitting device having the configuration shown in FIG. 11, the transparent resin layer 103 has a function of guiding a part of the light emitted from each of the LEDs 101a, 101b, and 101c toward the light detection elements 104a, 104b, and 104c. The thickness dimension of the transparent resin layer 103 is set. In addition, in the light emitting device having the configuration shown in FIG. 11, the three spectral filters 105a, 105b, and 105c that selectively transmit light in the wavelength regions of the light emission colors of the respective LEDs 101a, 101b, and 101c 104b and 104c are provided alternatively on the light receiving surface side, and light in the wavelength band of each LED 101a, 101b and 101c is detected simultaneously and separately by the three photodetectors 104a, 104b and 104c. Can be done. Therefore, in the illuminating device including the light emitting device having the configuration shown in FIG. 11, the control circuit unit feedback-controls each of the currents flowing from the drive circuit unit to the LEDs 101a, 101b, and 101c, whereby the LEDs 101a, Regardless of differences in the light output of 101b and 101c over time, mixed light with a desired light color and color temperature (for example, LED 101a emits red, LED 101b emits green, and LED 101c emits blue) White light) can be obtained.

  Further, in Patent Document 1, light is emitted by controlling the drive circuit unit by the control circuit unit so that the period in which the LED 101a emits light, the period in which the LED 101b emits light, and the period in which the LED 101c emits light appear in time series. A technique is also disclosed in which the light output of a plurality of types of LEDs 101a, 101b, and 101c having different colors is individually detected by a single light detection element.

Further, in Patent Document 1, as shown in FIG. 12, the LEDs 101 having the same emission color are mounted on the inner bottom surface of each storage recess 102 a formed on one surface of the mounting substrate 102, and There has also been proposed a light emitting device in which the light detection element 104 is mounted on one surface and each LED 101 and the light detection element 104 are covered with a transparent resin layer 103.
JP 2002-344031 A

  However, as shown in FIG. 12, the light detection element 104 is mounted on the one surface of the mounting substrate 102 in which the housing recess 102 a for housing the LED 101 is formed on one surface, and the LED 101 and the light detection element are formed by the transparent resin layer 103. In the light emitting device configured to cover 104, it is necessary to separately secure a space for arranging the light detection element 104 on the one surface of the mounting substrate 102, and the planar size of the mounting substrate 102 becomes large. The mounting area on a circuit board such as a printed board becomes large.

  The present invention has been made in view of the above reasons, and an object of the present invention is to provide a method for manufacturing a light-emitting device that can be downsized while providing a light detection element on a mounting substrate.

  The invention of claim 1 includes an LED chip and a package constituted by a mounting substrate in which at least a storage recess for storing the LED chip is formed on one surface, and the mounting substrate is inward from a peripheral portion of the storage recess. And a light detection element that detects light emitted from the LED chip is provided on the protrusion, and the mounting substrate is formed using the first silicon substrate. The LED mounting substrate on which the LED chip is mounted on the one surface side and the second silicon substrate are formed, and the light mounting window is formed to be opposed to the one surface side of the LED mounting substrate. A light detection element forming substrate on which a light detection element is formed, and an opening window formed between the LED mounting substrate and the light detection element formation substrate, which is formed using a third silicon substrate, and communicates with the light extraction window. Formed A space in which the inner surface of the opening window is composed of an intermediate layer substrate that serves as a mirror that guides light emitted from the LED chip to the light detection element, and is surrounded by the LED mounting substrate, the intermediate layer substrate, and the light detection element formation substrate Is a method of manufacturing a light emitting device comprising the housing recess, wherein the first bonding step of bonding the second silicon substrate on which the light detection element is formed and the intermediate layer substrate, and the first bonding A polishing step of polishing the second silicon substrate to a desired thickness after the step, a light extraction window forming step of forming a light extraction window on the second silicon substrate after the polishing step, and a light extraction window forming step And a second bonding step of bonding the LED mounting substrate on which the LED chip is mounted and the intermediate layer substrate later.

  According to the present invention, it is possible to provide a light emitting device that can be miniaturized while providing the light detection element on the mounting substrate. Moreover, according to this invention, the relative positional accuracy of the mirror in an intermediate | middle layer board | substrate and the photon detection element in a photon detection element formation board | substrate can be improved.

  The invention according to claim 2 is the invention according to claim 1, wherein in the first joining step and the second joining step, the joining surfaces are brought into contact with each other after the joining surfaces are activated before joining. It is characterized by joining.

  According to this invention, it is possible to prevent the junction temperature of the LED chip from exceeding the maximum junction temperature in the second bonding step.

  According to a third aspect of the invention, in the invention of the second aspect, a through-hole wiring electrically connected to the photodetecting element is formed in the intermediate layer substrate, and the LED chip is electrically connected to the LED mounting substrate. Connected through hole wiring and through hole wiring electrically connected to the through hole wiring of the intermediate layer substrate are formed, and the intermediate layer substrate and the light detection element forming substrate are the same as the LED mounting substrate In the first bonding step, the activated bonding metal layers and the activated conductor patterns of the second silicon substrate and the intermediate layer substrate are bonded at room temperature in the first bonding step. In the second bonding step, the bonding portion between the conductor patterns is shifted from the region overlapping the through-hole wiring formed in the intermediate layer substrate. The activated bonding metal layers and the activated conductor patterns are bonded to each other at room temperature, and the bonding portion between the conductor patterns overlaps the through-hole wiring formed on the LED mounting substrate. And it has shifted from the area | region which overlaps with the said through-hole wiring formed in the said intermediate | middle layer formation board | substrate.

  According to the present invention, the flatness of the bonding surfaces of the conductor patterns can be increased in the first bonding step, the bonding yield can be increased, and the bonding reliability can be increased. In this bonding step, the flatness of the bonding surfaces of the conductor patterns can be increased, the bonding yield can be increased, and the bonding reliability can be increased.

  According to a fourth aspect of the present invention, in the first to third aspects of the present invention, a wafer level package structure is formed by performing each of the steps at a wafer level, and the light emitting device is formed from the wafer level package structure. A dicing process for dividing is provided.

  According to the present invention, the LED mounting substrate, the intermediate layer substrate, and the photodetecting element forming substrate have the same outer size, so that a small package can be realized and manufacturing is facilitated.

  According to a fifth aspect of the present invention, in the invention of the fourth aspect, between the second bonding step and the dicing step, the housing recess of the mounting substrate is filled with a sealing resin to seal the LED chip. A sealing portion forming step for forming a sealing portion to be stopped is provided.

  According to this invention, the LED chip can be sealed before the dicing step.

  According to a sixth aspect of the present invention, in the invention of the fifth aspect, the package is joined to the mounting substrate so as to close the housing recess on the mounting substrate and the one surface side of the mounting substrate. And a third joining step for joining the mounting substrate and the translucent member between the sealing portion forming step and the dicing step.

  According to the present invention, the translucent member has the same outer size as the LED mounting substrate, so that a small package can be realized and manufacture is facilitated.

  According to the first aspect of the present invention, there is an effect that it is possible to provide a light emitting device that can be downsized while providing the light detection element on the mounting substrate.

  Hereinafter, the light-emitting device of this embodiment will be described with reference to FIGS.

  As shown in FIG. 2, the light emitting device of the present embodiment includes one LED chip 1 that emits visible light (for example, red light, green light, blue light, and the like) and a storage recess 2 a that stores the LED chip 1. Is mounted on the mounting substrate 2 in such a manner that the LED chip 1 is mounted on the inner bottom surface of the housing recess 2a and the housing recess 2a is closed on the one surface side of the mounting substrate 2. Translucent member 3, photodetecting element 4 provided on mounting substrate 2 for detecting light emitted from LED chip 1, and translucent sealing resin filled in housing recess 2 a of mounting substrate 2 It is provided with a sealing portion 5 that is made of (for example, a silicone resin, an acrylic resin, etc.) and seals the LED chip 1 and the bonding wire 14 (see FIG. 3) connected to the LED chip 1. Here, the mounting substrate 2 has a hook-like protrusion 2c protruding inward from the peripheral portion of the housing recess 2a on the one surface side, and the light detection element 4 is provided on the protrusion 2c. ing. 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.

  As shown in FIGS. 2 to 4, the mounting substrate 2 is disposed so as to be opposed to the rectangular plate-shaped LED mounting substrate 20 on which the LED chip 1 is mounted on one surface side and the LED mounting substrate 20 on the one surface side. The circular light extraction window 41 and the light detection element forming substrate 40 on which the light detection element 4 is formed, and the light extraction window interposed between the LED mounting substrate 20 and the light detection element formation substrate 40. The space surrounded by the LED mounting substrate 20, the intermediate layer substrate 30, and the photodetecting element forming substrate 40 is configured by the intermediate layer substrate 30 in which the rectangular opening window 31 communicating with the terminal 41 is formed. The storage recess 2a is configured. 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 chip 1 constitutes an LED, the LED mounting substrate 20 constitutes an LED mounting portion on which the LED is mounted, and the intermediate layer substrate 30 and the light detection element forming substrate 40 include the LED mounting portion. The wall portion 2b provided in the peripheral portion of the region where the LED is mounted is configured, and the portion of the light detection element forming substrate 40 that protrudes over the opening window 31 of the intermediate layer substrate 30 is from the tip portion of the wall portion 2b. The protrusion part 2c which protrudes inward 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 indicates that the opening area of the opening window 31 gradually increases as the distance from the LED mounting substrate 20 increases), and constitutes a mirror 2d that reflects light emitted from the LED chip 1 forward. 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 chip 1 to the side.

  As shown in FIGS. 5 and 6, the LED mounting substrate 20 is electrically connected to each of both electrodes of the LED chip 1 on one surface side (left surface side in FIG. 5C) of the silicon substrate 20 a. Two conductor patterns 25a and 25a are formed, and two conductor patterns 25b that are electrically connected to the light detection element 4 through two through-hole wirings 34 and 34, which will be described later, formed on the intermediate layer substrate 30. , 25b, and four external connection electrodes 27a, 27a, 27b formed on the other surface side (right side in FIG. 5 (c)) of each conductor pattern 25a, 25a, 25b, 25b and the silicon substrate 20a. 27b and 27b are electrically connected through the through-hole wiring 24, respectively. 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 chip 1 in the present embodiment is a visible light LED chip 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 has one of the two conductor patterns 25a, 25a to which the LED chip 1 is electrically connected, the rectangular die pad portion 25aa to which the LED chip 1 is die-bonded. 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 chip 1 is die-bonded to the die pad portion 25aa of the one conductor pattern 25a, and the electrode on the die pad portion 25aa side is joined to and electrically connected to the die pad portion 25aa, and the electrode on the light extraction surface side. Is electrically connected to the other conductor pattern 25 a via the bonding wire 14.

  The LED mounting substrate 20 has a rectangular heat radiation pad portion 28 made of a metal material having a higher thermal conductivity than the silicon substrate 20a on the other surface side of the silicon substrate 20a. The die pad portion 25aa And the heat dissipating pad portion 28 through a plurality of (in this embodiment, nine) cylindrical thermal vias 26 made of a metal material (for example, Cu) having a thermal conductivity higher than that of the silicon substrate 20a. The heat generated in the LED chip 1 is dissipated through the thermal vias 26 and the heat dissipating pad portion 28.

  By the way, the LED mounting substrate 20 has, in the silicon substrate 20a, four through holes 22a in which the above-described four through-hole wirings 24 are formed inside, and each of the nine thermal vias 26 in the inside. Nine through holes 22b are provided in the thickness direction, and an insulating film made of a thermal oxide film (silicon oxide film) straddling the one surface and the other surface of the silicon substrate 20a and the inner surfaces of the through holes 22a and 22b. 23, each conductor pattern 25a, 25a, 25b, 25b, bonding metal layer 29, each external connection electrode 27a, 27a, 27b, 27b, heat radiation pad 28, each through-hole wiring 24, and each The thermal 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 heat radiation pad portion 28 are formed on the insulating film 23. And an Au film formed on the Ti film, and are 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.

  As shown in FIGS. 7 and 8, the intermediate layer substrate 30 is bonded to the two conductor patterns 27b and 27b of the LED mounting substrate 20 on one surface side (right side in FIG. 7C) of the silicon substrate 30a. Thus, two conductive patterns 35 and 35 that are electrically connected are formed, and a bonding metal layer 36 that is bonded to the bonding metal layer 29 of the LED mounting substrate 20 is formed. In addition, the intermediate layer substrate 30 is a conductor pattern electrically connected to the conductor patterns 35 and 35 via the through-hole wirings 34 and 34 on the other surface side (the left side in FIG. 7C) of the silicon substrate 30a. 37 and 37 are formed, and a bonding metal layer 38 for bonding to the light detection element forming substrate 40 is formed.

  Further, the intermediate layer substrate 30 has two 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 35, 35, 37, 37 and each bonding metal layer 36, 38 are formed. Is electrically insulated from the silicon substrate 30a. Here, each of the conductor patterns 35, 35, 37, 37 and each of the bonding metal layers 36, 38 is a laminated film of a Ti film formed on the insulating film 33 and an Au film formed on the Ti film. Constructed and formed simultaneously. 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.

  As shown in FIGS. 9 and 10, the photodetecting element forming substrate 40 has two conductor patterns 37, 37 of the intermediate layer substrate 30 on one surface side of the silicon substrate 40a (right side in FIG. 9C). Two conductor patterns 47 a and 47 b that are bonded and electrically connected are formed, and a bonding metal layer 48 that is bonded to the bonding metal layer 38 of the intermediate layer substrate 30 is formed. Here, the photodetecting element 4 is constituted by a photodiode, and one of the two conductor patterns 47a and 47b formed on the photodetecting element forming substrate 40 (the upper conductive pattern 47a in FIG. 10). Is electrically connected to the p-type region 4a of the photodiode constituting the photodetecting element 4, and the other conductor pattern 47b (lower conductor pattern 47b in FIG. 10) is connected to the n-type region 4b of the photodiode. It is electrically connected to the silicon substrate 40a that constitutes it.

  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. Further, in the light detection element forming substrate 40, the one conductor pattern 47a is electrically connected to the p-type region 4a through the contact hole 43a formed in the insulating film 43, and the other conductor pattern 47b is connected to the insulating film 43. The n-type region 4b is electrically connected through the formed contact hole 43b. 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 the formation of the mounting substrate 2 described above, for example, as shown in FIG. 1, the silicon substrate 40a and the intermediate layer on which the light detecting element 4, the insulating film 43, the conductor patterns 47a and 47b, and the bonding metal layer 48 are formed. After performing a first bonding step for bonding the substrate 30 to the substrate 30 by a room temperature bonding method capable of direct bonding at a low temperature, a polishing step for polishing the silicon substrate 40a to a desired thickness is performed, and then inductively coupled plasma ( The light detection element forming substrate 40 is completed by performing the light extraction window forming step of forming the light extraction window 41 on the silicon substrate 40a using an ICP) type dry etching apparatus or the like, and then the LED chip 1 is mounted and bonded. If a second bonding step is performed in which the LED mounting substrate 20 to which the wires 14 are connected and the intermediate layer substrate 30 are bonded by a room temperature bonding method or the like. There. 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 present embodiment, the silicon substrate 20a constitutes a first silicon substrate, the silicon substrate 40a constitutes a second silicon substrate, and the silicon substrate 30a constitutes a third silicon substrate.

  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 all of the light emitted from the LED chip 1 is formed on the light extraction surface opposite to the mounting substrate 2 side. A fine concavo-convex structure that suppresses 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. The period of the fine concavo-convex structure may be set as appropriate within a range of about ¼ to 100 times the emission peak wavelength of the LED chip 1.

  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, light extraction window forming step, The mounting substrate 2 and the translucent member after the bonding step 2, 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 bonding process for bonding 3 to the wafer 3 at the wafer level, and then divided into the size of the mounting substrate 2 by a dicing process. 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. Further, the relative positional accuracy between the mirror 2d on the intermediate layer substrate 30 and the light detecting element 4 on the light detecting element forming substrate 40 can be increased, and the light emitted from the LED chip 1 to the side is reflected by the mirror 2d. Then, it is guided to the light detection element 4.

  In the light emitting device of the present embodiment described above, the housing recess 2a for housing the LED chip 1 is formed on one surface, and the mounting substrate 2 on which the LED chip 1 is mounted on the inner bottom surface of the housing recess 2a Since the projecting portion 2c projecting inward from the peripheral portion of the location 2a and the light detecting element 4 for detecting the light emitted from the LED chip 1 is provided on the projecting portion 2c, one of the mounting substrates 2 is provided. There is no need to separately provide a space for disposing the light detection element 4 around the housing recess 2a on the front surface side, and the light detection element 4 can be downsized while being provided on the mounting substrate 2.

  Further, in the light emitting device of this embodiment, the through hole wiring 24 that electrically connects the external connection electrode 27a on the other surface side of the mounting substrate 2 and the LED chip 1 is formed on the mounting substrate 2. The mounting substrate 2 can be reduced in size as compared with the case where the wiring electrically connected to the LED chip 1 is routed on the one surface side of the mounting substrate 2. In the present embodiment, since the mounting substrate 2 is formed using a plurality of silicon substrates 20a, 30a, and 40a, the light detection element 4 such as a photodiode can be easily formed in the mounting substrate 2. This is possible and the cost can be reduced.

  In the light emitting device of the present embodiment, since the light detection element 4 is provided on the mounting substrate 2, for example, a light emitting device employing a red LED chip as the LED chip 1 and a green LED chip as the LED chip 1 are employed. A light emitting device and a light emitting device employing a blue LED chip as the LED chip 1 are arranged close to each other on the same circuit board, and a drive circuit unit that drives the LED chip 1 of each light emitting apparatus on the circuit board; In addition, a control circuit unit that feedback-controls the current flowing from the drive circuit unit to the LED chip 1 of each emission color is provided so that the light intensity detected by each photodetecting element 4 is maintained at each target value. Thus, the light output of the LED chip 1 of each emission color can be controlled separately based on the output of each light detection element 4, and the LED chip 1 for each emission color can be controlled. The light output of the difference such as to depend not mixed color light of aging (here, white light) can improve the accuracy of the light color and color temperature. In short, desired mixed color light can be stably obtained.

  Further, in the light emitting device of the present embodiment, disturbance light can be prevented from entering the light receiving surface of the light detection element 4, and the S / N ratio of the output of the light detection element 4 can be further increased. .

  In the conventional configuration shown in FIG. 12, it is necessary to totally reflect a part of the light from the LED 101 at the interface between the transparent resin layer 103 and the air. Since the fine concavo-convex structure for suppressing the total reflection of the light emitted from the LED chip 1 is formed on the light extraction surface of the transparent member 3, the medium existing opposite to the mounting substrate 2 side in the transparent member 3 Total reflection of light caused by the difference in refractive index between (air) and the translucent member 3 can be suppressed, and light extraction efficiency can be increased.

  Further, in the present embodiment, since the room temperature bonding method capable of direct bonding at a low temperature is adopted in each of the above-described bonding processes in forming the mounting substrate 2, the junction temperature of the LED chip 1 is maximized in each bonding process. It is possible to prevent the junction temperature from being exceeded.

  Further, in the light emitting device of the present embodiment, the thermal via 26 that is thermally coupled to the LED chip 1 is provided on the LED mounting substrate 20 of the mounting substrate 2, so that the heat generated in the LED chip 1 is efficiently released to the outside. Since the temperature rise of the junction temperature of the LED chip 1 can be suppressed, the input power can be increased and the light output can be increased.

  In the present embodiment, one LED chip 1 is mounted on the inner bottom surface of the housing recess 2a of the mounting substrate 2. However, the number of LED chips 1 is not particularly limited, and a plurality of light emission colors are the same. The LED chip 1 may be mounted on the inner bottom surface of the storage recess 2a.

It is explanatory drawing of the formation method of the mounting substrate in the light-emitting device of embodiment. It is a schematic sectional drawing of a light-emitting device same as the above. It is a general | schematic disassembled perspective view of a light-emitting device same as the above. The mounting board | substrate is shown, (a) is a schematic plan view, (b) is A-A 'schematic sectional drawing of (a), (c) is B-B' schematic sectional drawing of (a). The board | substrate for LED mounting same as the above is shown, (a) is a schematic plan view, (b) is AA 'schematic sectional drawing of (a), (c) is BB' schematic sectional drawing of (a). . It is a schematic bottom view of the board | substrate for LED mounting in the same as the above. The intermediate | middle layer board | substrate in the same is shown, (a) is a schematic plan view, (b) is A-A 'schematic sectional drawing of (a), (c) is B-B' schematic sectional drawing of (a). It is a schematic bottom view of the intermediate | middle layer board | substrate in the same as the above. The optical detection element formation board in the same as above is shown, (a) is a schematic plan view, (b) is an AA 'schematic sectional view of (a), (c) is a BB' schematic sectional view of (a). is there. It is a schematic bottom view of the optical detection element formation board | substrate in the same as the above. A prior art example is shown, (a) is a schematic plan view, and (b) is a schematic cross-sectional view along A-A 'of (a). It is a schematic sectional drawing which shows another prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 LED chip 2 Mounting board | substrate 2a Storage recess 2c Protrusion part 4 Photodetection element 20 LED mounting board | substrate 20a Silicon substrate (1st silicon substrate)
24 Through-hole wiring 30 Intermediate layer substrate 30a Silicon substrate (third silicon substrate)
31 Opening window 34 Through-hole wiring 40 Photodetecting element forming substrate 40a Silicon substrate (second silicon substrate)
41 Light extraction window

Claims (6)

  An LED chip and a package formed of a mounting substrate in which at least a storage recess for storing the LED chip is formed on one surface, and the mounting substrate has a protruding portion that protrudes inward from the peripheral portion of the storage recess. In addition, a light detection element for detecting light emitted from the LED chip is provided in the projecting portion, and the mounting substrate is formed using the first silicon substrate, and the LED chip is on the one surface side. The LED mounting substrate and the second silicon substrate mounted on the LED mounting substrate are opposed to the one surface side of the LED mounting substrate to form a light extraction window and a light detection element. An opening window formed between the LED mounting substrate and the light detection element formation substrate is formed by using the light detection element formation substrate and the third silicon substrate, and communicates with the light extraction window. Side An intermediate layer substrate that serves as a mirror that guides light emitted from the ED chip to the light detection element, and a space surrounded by the LED mounting substrate, the intermediate layer substrate, and the light detection element formation substrate forms the storage recess. A method for manufacturing a light-emitting device comprising the first bonding step for bonding the second silicon substrate on which the light detection element is formed and the intermediate layer substrate, and the second after the first bonding step. The LED chip is mounted after the polishing step of polishing the silicon substrate to a desired thickness, the light extraction window forming step of forming the light extraction window on the second silicon substrate after the polishing step, and the light extraction window forming step And a second bonding step for bonding the LED mounting substrate and the intermediate layer substrate.   2. The room temperature bonding according to claim 1, wherein in the first bonding step and the second bonding step, the bonding surfaces are brought into contact with each other after the bonding surfaces are activated before bonding. Manufacturing method of light-emitting device.   A through-hole wiring electrically connected to the photodetecting element is formed in the intermediate layer substrate, and the through-hole wiring electrically connected to the LED chip and the intermediate layer substrate are electrically connected to the LED mounting substrate. A through-hole wiring electrically connected to the through-hole wiring is formed, and the intermediate layer substrate and the light detection element forming substrate are formed to have the same outer dimensions as the LED mounting substrate, and the first bonding step Then, the activated bonding metal layers of the second silicon substrate and the intermediate layer substrate and the activated conductor patterns are bonded at room temperature, and the bonding portion of the conductive patterns is defined as the intermediate layer. In the second bonding step, the activated bonding metal layers of the LED mounting substrate and the intermediate layer substrate and the active metal layers are shifted from the region overlapping the through-hole wiring formed on the substrate. The conductor patterns thus formed are joined at room temperature, and the joint portions of the conductor patterns are overlapped with the through-hole wiring formed in the LED mounting substrate and the through-hole formed in the intermediate layer forming substrate. 3. The method for manufacturing a light emitting device according to claim 2, wherein the method is shifted from a region overlapping with the wiring.   4. A dicing process for dividing the wafer level package structure into the light emitting device by forming each wafer level at a wafer level to form a wafer level package structure. The manufacturing method of the light-emitting device of any one of these.   A sealing portion forming step of forming a sealing portion for sealing the LED chip by filling the housing recess of the mounting substrate with a sealing resin between the second bonding step and the dicing step. The method for manufacturing a light emitting device according to claim 4, further comprising:   The package is composed of the mounting substrate and a translucent member bonded to the mounting substrate so as to close the housing recess on the one surface side of the mounting substrate, and the sealing portion forming step and the The method for manufacturing a light emitting device according to claim 5, further comprising a third joining step for joining the mounting substrate and the translucent member between the dicing steps.

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