WO2017217549A1 - Light emitting device - Google Patents

Light emitting device Download PDF

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Publication number
WO2017217549A1
WO2017217549A1 PCT/JP2017/022417 JP2017022417W WO2017217549A1 WO 2017217549 A1 WO2017217549 A1 WO 2017217549A1 JP 2017022417 W JP2017022417 W JP 2017022417W WO 2017217549 A1 WO2017217549 A1 WO 2017217549A1
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WO
WIPO (PCT)
Prior art keywords
phosphor
led element
light emitting
emitting device
sealing resin
Prior art date
Application number
PCT/JP2017/022417
Other languages
French (fr)
Japanese (ja)
Inventor
加藤　達也
拓也 舟久保
恒太 吉澤
和 小山田
Original Assignee
シチズン電子株式会社
シチズン時計株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by シチズン電子株式会社, シチズン時計株式会社 filed Critical シチズン電子株式会社
Priority to JP2018524055A priority Critical patent/JP6739527B2/en
Publication of WO2017217549A1 publication Critical patent/WO2017217549A1/en

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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L33/00—Semiconductor devices having potential barriers specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L33/48—Semiconductor devices having potential barriers specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by the semiconductor body packages
    • H01L33/50—Wavelength conversion elements
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L33/00—Semiconductor devices having potential barriers specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L33/48—Semiconductor devices having potential barriers specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by the semiconductor body packages
    • H01L33/52—Encapsulations
    • H01L33/54—Encapsulations having a particular shape

Definitions

  • the present invention relates to a light emitting device.
  • LED package in which an LED (light emitting diode) element is mounted on a substrate and the LED element is sealed with a translucent resin containing a phosphor.
  • LED light emitting diode
  • white light or the like can be obtained depending on the application by mixing light from the LED element and light obtained by exciting the phosphor with the light from the LED element.
  • Patent Document 1 describes a light-emitting device including a light-emitting element, a package having a recess in which the light-emitting element is disposed, and a resin containing a phosphor and a filler.
  • the specific gravity relationship is (phosphor)> (filler)> (resin)
  • the filler deposition layer is disposed on the phosphor deposition layer covering the bottom surface side of the recess and the top surface of the light emitting element
  • the phosphor deposited layer disposed on the bottom surface side of the recess is lower than the height of the light emitting layer of the light emitting element
  • the filler deposited layer disposed on the phosphor deposited layer disposed on the bottom surface side of the recess is the side surface of the light emitting layer. Is covered.
  • Patent Document 2 discloses a light emitting device that includes a base, a light emitting element mounted on the upper surface of the base via a mount, and a sealing resin that seals the light emitting element.
  • a phosphor-containing first layer covering the light emitting element, a phosphor-containing second layer formed on the upper surface of the substrate around the mount portion, and a filler formed on the phosphor-containing second layer around the mount portion A light emitting device having an inclusion layer is described.
  • Patent Document 3 discloses a light conversion member made of glass containing dispersed phosphor particles, in which nanofillers having a 50% particle size of 50 nm or less are adsorbed on the surface of the phosphor particles. Further, there is described a light conversion member further containing a heat-resistant filler having a 50% particle size D50 of 5 to 30 ⁇ m dispersed therein.
  • JP 2016-026404 A International Publication No. 2012/029695 Japanese Patent Laying-Open No. 2015-046579
  • the phosphor in the sealing resin Since the phosphor in the sealing resin generates heat when excited by the light from the LED element, if the phosphor is dispersed in the sealing resin, the temperature of the sealing resin increases during light emission, This leads to a decrease in lifetime and light emission efficiency of the LED element. For this reason, the phosphor is naturally settling in the sealing resin during manufacturing and then the sealing resin is cured, so that the phosphor is disposed on the side closer to the mounting substrate of the LED element and the heat from the phosphor is mounted. It is desirable to facilitate release to the substrate side.
  • the phosphor when the phosphor is completely settled in the sealing resin, the phosphor is deposited on the upper surface of the mounting substrate and the upper surface of the LED element, but the phosphor layer is formed on the side surface and corners (obliquely upward) of the LED element. Is difficult to form.
  • the wavelength conversion by the phosphor with respect to the light emitted obliquely upward of the LED element becomes insufficient, the color corresponding to the emission wavelength of the LED element becomes strong in that direction, and color unevenness occurs on the light emitting surface of the light emitting device. Occurs (that is, angle directivity occurs in the chromaticity of the emitted light).
  • a “semi-sedimentation state” that is an intermediate between the state in which the phosphor is dispersed and the state in which the phosphor is settled in the sealing resin.
  • the phosphor settled state is obtained by leaving the sealing resin in an uncured state, for example, for several hours while manufacturing the light emitting device, so in principle, the sealing resin is cured during sedimentation. If so, it is considered to be in a semi-sedimentation state.
  • the variation of each product becomes large, and stable production cannot be performed, so it is practically difficult to take such a method.
  • the present invention can be manufactured without reducing the yield, heat generated by the phosphor that converts the wavelength of the light from the LED element is easily emitted through the mounting substrate, and angular directivity of the chromaticity of the emitted light occurs. It is an object to provide a light-emitting device that is difficult.
  • the sealing resin is formed by depositing a phosphor so as to cover the upper surface and side surfaces of the LED element and the oblique upper part of the LED element, and rises along the shape of the LED element. Further, a light emitting device having a sedimented layer of phosphor is provided.
  • the sealing resin preferably further contains a filler having an average particle diameter in the range of 1 ⁇ m to 100 ⁇ m.
  • the sealing resin is disposed on the upper side of the sedimentation layer, and is disposed on the upper side of the dispersion layer containing the phosphor in a higher concentration toward the lower side, and the phosphor is disposed above the dispersion layer. It is preferable to further have a resin layer contained at a low concentration.
  • the mounting substrate has a mounting portion that is one step higher than the peripheral portion, and the LED element is mounted on the upper surface of the mounting portion.
  • the above light-emitting device can be manufactured without reducing the yield, heat generated by the phosphor that converts the wavelength of light from the LED element is easily emitted through the mounting substrate, and angle directivity of the chromaticity of the emitted light occurs. Hateful.
  • FIG. (A) And (B) is sectional drawing and the top view of the light-emitting device 1.
  • FIG. (A) And (B) is the cross-sectional photograph of the light-emitting device 1 'and the light-emitting device 1 of a comparative example.
  • (A) to (D) are schematic diagrams for explaining the phosphor layers of the light emitting devices 1 and 1 ′.
  • (A) And (B) is sectional drawing and the top view of the light-emitting device 2.
  • FIG. (A) to (D) are schematic diagrams for explaining the phosphor layers of the light emitting devices 2 and 2 ′.
  • (A) to (D) are schematic views for explaining the phosphor layers of the light emitting devices 3 and 3 ′.
  • (A) to (C) are enlarged photographs showing a part of the sealing resin 30 of the light emitting device 1.
  • the light-emitting device 1 is a light-emitting device (LED package) that includes an LED element as a light-emitting element and emits white light or the like using wavelength conversion by a phosphor, and is used as an LED light source for various illuminations, for example.
  • the light emitting device 1 includes a mounting substrate 10, an LED element 20, and a sealing resin 30 as main components. Note that the number of LED elements 20 is not limited to one, and the light emitting device may have a plurality of LED elements 20 mounted on the mounting substrate 10.
  • the mounting substrate 10 has two connection electrodes (not shown) for connecting the LED element 20 to an external power supply, and is a substrate on which the LED element 20 is mounted.
  • the mounting substrate 10 may be a ceramic substrate, or an insulating circuit in which a metal substrate such as aluminum or copper excellent in heat resistance and heat dissipation, and a wiring pattern and connection electrodes of the LED element 20 are formed. It may be a laminate of a substrate.
  • the mounting substrate 10 is a base body of an LED package having a recess in which the LED element 20 is mounted and filled with the sealing resin 30, and two lead electrodes for connecting the LED element 20 to an external power source are provided. There may be.
  • the LED element 20 is an element composed of, for example, a gallium nitride compound semiconductor that emits light having a wavelength ranging from the ultraviolet region to the blue region.
  • the LED element 20 is described as a blue LED element that emits blue light having an emission wavelength band of about 450 to 460 nm.
  • the LED element 20 may be an element that emits light of other wavelengths. Good.
  • the LED element 20 is mounted on the upper surface of the mounting substrate 10 by die bonding, and the positive and negative electrodes of the LED element 20 are electrically connected to connection electrodes on the mounting substrate 10 by two bonding wires 21 (hereinafter simply referred to as wires 21). Connected.
  • the LED elements 20 are also electrically connected to each other by the wire 21.
  • the mounting method of the LED element 20 is not limited to wire bonding, and may be flip chip.
  • the sealing resin 30 is a translucent resin such as an epoxy resin or a silicone resin, and integrally seals the LED element 20 and the wire 21. Moreover, the sealing resin 30 contains a phosphor, a filler, and a nanofiller that are excited by the LED element 20.
  • the light-emitting device 1 may have a resin frame that is a dam material that prevents the sealing resin 30 from flowing out. In that case, the inner region surrounded by the frame is filled with the sealing resin 30. The LED element 20 and the wire 21 may be sealed.
  • the phosphor contained in the sealing resin 30 may be one type or plural types.
  • the sealing resin 30 contains, for example, a yellow phosphor such as YAG (Yttrium Aluminum Garnet) and a red phosphor such as CaAlSiN 3 : Eu 2+ .
  • the light emitting device 1 emits white light obtained by mixing the blue light from the LED element 20 and the yellow light and red light obtained by exciting the yellow phosphor and the red phosphor thereby.
  • the average particle diameter of the phosphor particles contained in the sealing resin 30 is, for example, about several tens of ⁇ m.
  • the filler contained in the sealing resin 30 is a micron-sized particulate inorganic material having an average particle diameter in the range of 1 ⁇ m to 100 ⁇ m.
  • the filler for example, silicon dioxide (silica), alumina, titania, zirconia, or magnesia may be used.
  • the filler functions as a scattering material that diffuses light in the sealing resin 30 and uniformly emits light in the entire light emitting region of the light emitting device 1 configured by the LED elements 20 and the sealing resin 30.
  • the nanofiller contained in the sealing resin 30 is a nanosized particulate inorganic material having an average particle diameter in the range of 1 nm to 100 nm.
  • the filler and nanofiller differ in particle size by about three orders of magnitude, but may be the same substance.
  • the nanofiller for example, silicon dioxide (silica), alumina, titania, zirconia, or magnesia may be used.
  • a nano filler has heat resistance and is easy to adsorb
  • the LED element 20 is fixed to the upper surface of the mounting substrate 10 by die bonding, and the positive and negative electrodes of the LED element 20 are connected to the connection electrodes on the mounting substrate 10 by wire bonding. Subsequently, the LED element 20 is filled with the translucent sealing resin 30 containing the phosphor, the filler, and the nanofiller, and the LED element 20 and the wire 21 are sealed. Then, while keeping the sealing resin 30 in an uncured state, for example, the phosphor and filler in the sealing resin 30 are naturally settled on the upper surface of the mounting substrate 10 and the LED element 20 over several hours, and after several hours have passed. For example, the sealing resin 30 is cured by heating. Thereby, the light emitting device 1 shown in FIGS. 1A and 1B is completed.
  • FIG. 2A is a cross-sectional photograph of the light-emitting device 1 ′ of the comparative example
  • FIG. 2B is a cross-sectional photograph of the light-emitting device 1.
  • the light emitting device 1 ′ has the same configuration as the above light emitting device 1 except for the sealing resin.
  • the sealing resin 30 ′ of the light emitting device 1 ′ is a silicone resin that contains a yellow phosphor, a red phosphor, and a silicon dioxide filler, and does not contain a nanofiller.
  • the sealing resin 30 of the light emitting device 1 is a silicone resin containing a yellow phosphor, a red phosphor, a silicon dioxide filler, and a nanofiller.
  • the average particle size of the yellow phosphor, the red phosphor and the filler is about several ⁇ m to several tens of ⁇ m, and the average particle size of the nanofiller is about several nm to several tens of nm. Further, the concentration of the nanofiller in the sealing resin 30 is about 0.5 wt%.
  • FIGS. 3A to 3D are schematic diagrams for explaining the phosphor layers of the light emitting devices 1 and 1 ′.
  • FIG. 3A shows a cross section immediately after the LED element 20 is sealed with the sealing resin 30 ′ during the manufacture of the light emitting device 1 ′
  • FIG. 3C shows a cross section immediately after the LED element 20 is sealed with the sealing resin 30 during the manufacture of the light emitting device 1
  • FIG. 3D shows the fluorescence in the sealing resin 30.
  • the cross section of the light-emitting device 1 which a body settled and became a finished product is shown.
  • the light emitting devices 1 and 1 ′ are in the same state immediately after sealing, but the settling states of the phosphors are different from each other.
  • the yellow phosphor, the red phosphor, and the filler particles in the sealing resin 30 ′ are formed on the upper surface of the mounting substrate 10 and the LED element. It has settled on the upper surface of 20. More specifically, in the light emitting device 1 ′, a yellow phosphor and a red phosphor sedimentation layer 31 ′ are formed on the upper surface of the mounting substrate 10 and the upper surface of the LED element 20. The resin layer 33 ′ is not contained in the resin layer 33 ′.
  • the sedimentation layer 31 ' is divided into a layer mainly containing a yellow phosphor and a layer mainly containing a red phosphor. In the light emitting device 1 ′, no phosphor sedimentation layer is formed at the corner (obliquely upward) of the upper surface of the LED element 20 indicated by a broken line 34 in FIG.
  • the yellow phosphor and the red phosphor in the sealing resin 30 are uniformly dispersed and completely settled. It is in a semi-sedimentation state that is in between. More specifically, the sealing resin 30 of the light-emitting device 1 is disposed on the sedimentary layer 31 of the yellow phosphor, the red phosphor and the filler, and on the sedimentary layer 31, and these phosphors are higher as they go downward. It has the dispersion layer 32 contained at a concentration, and the resin layer 33 that is disposed on the upper side of the dispersion layer 32 and substantially does not contain phosphor particles. Although some phosphor particles may exist in the resin layer 33, the concentration of the phosphor in the resin layer 33 is lower than the concentration of the phosphor in the dispersion layer 32 (the upper end thereof).
  • the boundary between the sedimentation layer 31 and the dispersion layer 32 and the boundary between the dispersion layer 32 and the resin layer 33 may not be clearly defined in practice, but are shown by broken lines in FIG. 3D for convenience.
  • the phosphor particles exist up to the upper end of the sealing resin 30, and the sealing resin 30 may be composed of only the sedimentation layer 31 and the dispersion layer 32.
  • the phosphor concentration at the upper end is preferably close to zero.
  • the phosphor settles so as to cover the upper surface and side surfaces of the LED element 20 and the diagonally upper portion of the LED element 20, and also on the corner portion of the upper surface of the LED element 20 indicated by the broken line 34 in FIG.
  • a fluorescent sedimentation layer 31 is formed.
  • the sedimentation layer 31 extends in the same direction as that shown in FIG. , And diagonally above (around the top four sides) isotropically.
  • the sedimented layer 31 of the light emitting device 1 is a continuous layer that rises along the shape of the LED element 20.
  • the sealing resin can be used if the concentration of the nanofiller in the sealing resin 30 is about 0.4 to 0.5 wt%.
  • the semi-sedimentation state shown in FIGS. 2 (B) and 3 (D) is obtained. In this semi-sedimentation state, some phosphor particles remain dispersed in the sealing resin and do not become a complete sedimentation state even after a lapse of time.
  • the sealing resin 30 contains nano filler, if the concentration is 0.2 wt% or less, the same sedimentation state as the light emitting device 1 ′ shown in FIG. 2 (A) and FIG. 3 (B) become. Further, when the concentration of the nanofiller in the sealing resin 30 exceeds 0.5 wt%, the phosphor does not settle sufficiently even after a sufficiently long time, and the dispersion is close to that shown in FIG. State is maintained. The higher the concentration of the nanofiller in the sealing resin 30, the more difficult it is for the phosphor to settle.
  • the temperature of the sealing resin 30 may increase excessively during light emission.
  • the upper limit of the amount of nanofiller that can be used is 0.5 wt% from the relationship with the heat resistance temperature of the sealing resin 30. It will be about. This upper limit is a value determined by the materials of the sealing resin and the nanofiller.
  • the sealing resin 30 Even if a high-viscosity resin is used as the sealing resin 30 for the purpose of making the phosphor difficult to settle, the sedimentation time only becomes longer depending on the viscosity.
  • the sedimentation state shown in FIG. In order to obtain the semi-sedimentation state shown in FIG. 2B and FIG. 3D, it is necessary to make the sealing resin 30 contain a nanofiller having a nano particle size.
  • the sealing resin 30 containing a phosphor, a filler, and a nanofiller is used as in the light emitting device 1, the phosphor settles to some extent, but does not become completely settled, and the phosphor is also present at the corner of the LED element 20.
  • a layer can be formed. Simply adding phosphor and micron-sized filler to the sealing resin 30 will cause the phosphor to settle completely, but adding a certain amount of nanofiller will allow the phosphor to be "softly" precipitated. become. If the nanofiller is contained in a certain amount, the semi-sedimentation state shown in FIG. 2 (B) and FIG.
  • the sealing resin 30 does not necessarily contain a filler in order to realize a semi-sediment state of the phosphor particles.
  • FIGS. 7A to 7C are enlarged photographs showing a part of the sealing resin 30 of the light emitting device 1.
  • the photographs in FIGS. 7A to 7C were taken at a magnification of 2,000, 3,000, and 20,000 times, respectively, and the length of the white line shown at the bottom of each photograph.
  • 7B corresponds to a part of FIG. 7A
  • FIG. 7C corresponds to an enlarged part of FIG. 7B.
  • Reference numerals 51 to 53 in FIG. 7A denote red phosphor, yellow phosphor and filler particles, respectively.
  • FIG. 7A micron-sized particles mixed in the sealing resin 30 are shown. It can be seen.
  • the particle size of the nanofiller is about three orders of magnitude smaller than that of the phosphor or filler, the particle itself is not visible in FIG. 7A, but a large number of particles gather to form an aggregate.
  • the phosphor In the light emitting device 1, the phosphor is not completely settled, and a phosphor layer having a constant thickness including the corners of the LED element 20 is formed.
  • the wavelength is converted by the phosphor in the sealing resin 30 in the same manner as the light emitted to the. Accordingly, in the light emitting device 1, angle directivity is hardly generated in the chromaticity of the emitted light, and thus color unevenness on the light emitting surface is hardly generated.
  • the semi-sediment state is realized, and the phosphor particles are arranged on the side close to the mounting substrate 10. Therefore, heat from the phosphor is easily released to the mounting substrate 10 side, and the sealing resin 30. It is also difficult to overheat.
  • the light-emitting device 1 cures the sealing resin during the precipitation without using the nanofiller. Compared to the case, the variation in chromaticity for each product is reduced, and the yield is improved.
  • the light emitting device 2 has the same configuration as the above light emitting device 1 except for the mounting substrate.
  • the mounting substrate 10 ′ of the light emitting device 2 has a mount portion 11 that is one step higher than the peripheral portion 12, and the LED element 20 is mounted on the upper surface of the mount portion 11.
  • the peripheral portion 12 of the mount portion 11 on which the LED element 20 is mounted on the mounting substrate 10 ′ is a recess that is one step lower than the mount portion 11.
  • the height of the mount portion 11 with respect to the peripheral portion 12 is preferably approximately the same as the height of the LED element 20.
  • the mount portion 11 may be configured integrally with the mounting substrate 10 ′, or a separate member from the mounting substrate 10 ′ may be attached to the mounting substrate 10 ′.
  • the number of LED elements 20 is not limited to one and may be plural.
  • FIGS. 5A to 5D are schematic views for explaining the phosphor layers of the light emitting devices 2 and 2 ′.
  • the light emitting device 2 ′ has the same configuration as the light emitting device 2 described above except for the sealing resin.
  • the sealing resin 40 ′ of the light emitting device 2 ′ contains a yellow phosphor, a red phosphor and a filler, but does not contain a nanofiller, like the sealing resin 30 ′ of the light emitting device 1 ′.
  • the sealing resin 40 of the light emitting device 2 contains a yellow phosphor, a red phosphor, a filler, and a nanofiller.
  • FIG. 5A shows a cross section immediately after the LED element 20 is sealed with the sealing resin 40 ′ during the manufacture of the light emitting device 2 ′
  • FIG. 5B shows the fluorescence in the sealing resin 40 ′.
  • the cross section of the light-emitting device 2 ′ in which the body has settled and becomes a finished product is shown.
  • FIG. 5C shows a cross section immediately after the LED element 20 is sealed with the sealing resin 40 at the time of manufacturing the light emitting device 2
  • FIG. 5D shows the fluorescence in the sealing resin 40.
  • the cross section of the light-emitting device 2 which the body settled and became a finished product is shown.
  • a yellow phosphor and a red phosphor sedimentation layer 41 are formed on the upper surface of the mount portion 11 and the peripheral portion 12 of the mounting substrate 10 ′ and the upper surface of the LED element 20. 'Is formed.
  • the sedimentation layer 41 ′ is divided into a layer mainly containing a yellow phosphor and a layer mainly containing a red phosphor.
  • Above the sedimentation layer 41 ' is a resin layer 43' that does not substantially contain phosphor particles.
  • no phosphor sedimentation layer is formed at the corner (obliquely upward) of the upper surface of the LED element 20 indicated by a broken line 44 in FIG.
  • the sealing resin 40 of the light emitting device 2 includes a sedimented layer 41, a dispersed layer 42, and a resin layer similar to the sedimented layer 31, the dispersed layer 32, and the resin layer 33 of the light emitting device 1. 43. Also in the light emitting device 2, the phosphor settles so as to cover the upper surface and side surfaces of the LED element 20 and the diagonally upper portion of the LED element 20, and also on the corner portion of the upper surface of the LED element 20 indicated by the broken line 44 in FIG. A sedimentation layer 41 of phosphor is formed. The sedimentation layer 41 also isotropically covers the four side surfaces, the top surface, and the diagonally upper side (around the four top surfaces) of the LED element 20.
  • the sealing resin 40 contains the nano filler, the phosphor does not completely settle, and a phosphor layer having a certain thickness including the corners of the LED element 20 is formed.
  • the angle directivity is less likely to occur in the chromaticity, and the color unevenness of the light emitting surface is less likely to occur.
  • the heat from the phosphor is easily released to the mounting substrate 10 ′ side, and the sealing resin is cured in the middle of the precipitation without using the nanofiller, so that the semi-sedimented state is obtained. Compared to realization, the product yield is also improved.
  • the light emitting device 1 since the side of the LED element 20 is buried in the sedimentation layer 31, the light emitted from the LED element 20 to the side is emitted light upward. Compared with, it passes through the phosphor layer longer.
  • the peripheral portion 12 since the peripheral portion 12 is at a lower position than the mount portion 11 on which the LED element 20 is mounted, the phosphor settled on the peripheral portion 12 is more LED element than in the light emitting device 1. It is in a lower position with respect to 20. Thereby, in the light emitting device 2, since the thickness of the sedimentation layer 41 on the side of the LED element 20, obliquely above and above is substantially uniform, wavelength conversion is performed almost uniformly regardless of the light emission direction.
  • the light emitting device 2 is less likely to cause color unevenness on the light emitting surface as compared to the light emitting device 1.
  • a useless phosphor layer is not formed between the LED elements 20, so that the light extraction efficiency is higher than that of the light emitting device 1.
  • FIGS. 6A to 6D are views showing the same states as FIGS. 3A to 3D, respectively.
  • the sealing resin 70 of the light emitting device 3 contains a yellow phosphor, a filler, and a nano filler
  • the sealing resin 70 'of the light emitting device 3' contains a yellow phosphor and a filler.
  • the sedimentation layer 71 ′ and the resin layer 73 ′ in the sealing resin 70 ′ shown in FIG. 6B are the same as those in FIG. 3 except that the sedimentation layer 71 ′ is not divided into a plurality of layers for each phosphor type. It is the same as the sedimentation layer 31 ′ and the resin layer 33 ′ of B).
  • the sealing resin 70 ′ having no nano filler the phosphor particles are completely settled, and thus settled at the corner of the upper surface of the LED element 20 (side of the light emitting layer 22 of the LED element 20) indicated by the broken line 74.
  • the sedimentation layer 71, the dispersion layer 72, and the resin layer 73 in the sealing resin 70 are the same as the sedimentation layer 31, the dispersion layer 32, and the resin layer 33 in FIG. 3 (D).
  • the sedimentation layer 71 of the phosphor particles is also formed at the corner portion of the upper surface of the LED element 20 indicated by the broken line 74, thereby realizing a semi-sedimentation state.
  • the side of the light emitting layer 22 of the LED element 20 is covered with the sedimented layer 71, and the semi-sedimented state is a state in which the light emitting layer of the LED element is covered with the sedimented layer of phosphor particles. It can be said that there is.
  • the sealing resin of the light emitting device may contain only a yellow phosphor as a phosphor so that white light can be emitted in combination with blue light.
  • a yellow phosphor having a particle diameter (median diameter D50) of 1 to 30 ⁇ m and a specific gravity of 2 to 10 g / cm 3 is used, and the concentration of the nanofiller with respect to the sealing resin 70 (silicone resin) is 0.2. It is preferable to be in the range of ⁇ 1.5 wt%.
  • the yellow phosphor completely settles when the nanofiller concentration is 0.2 wt% or less, and remains dispersed in the sealing resin 70 when the nanofiller concentration exceeds 1.5 wt%.
  • the sealing resin 70 contains 0.2 to 1.5 wt% of nanofiller, a semi-sedimentation state is realized. Therefore, even in the light emitting device 3 shown in FIG. 6D, color unevenness on the light emitting surface of the light emitting device. And overheating of the sealing resin 70 is less likely to occur.

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  • Microelectronics & Electronic Packaging (AREA)
  • Manufacturing & Machinery (AREA)
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  • Power Engineering (AREA)
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Abstract

Provided is a light emitting device which can be produced without causing lowering of yield, and in which heat generated by a fluorescent body for converting the wavelength of light from an LED element is easily released through a mount substrate, and which is less likely to cause angle directivity in the chromaticity of outgoing light. The light emitting device has: a mount substrate; an LED element mounted on the mount substrate; and a translucent sealing resin which comprises a fluorescent body to be excited by the LED element, and a nanofiller having an average particle diameter falling within the range of 1-100 nm, and which seals the LED element, wherein the sealing resin has a fluorescent body precipitation layer that is formed by precipitation of the fluorescent body so as to cover the top and the lateral surfaces of the LED element and the areas obliquely above the LED element, and that is raised so as to follow the contour of the LED element.

Description

発光装置Light emitting device
　本発明は、発光装置に関する。 The present invention relates to a light emitting device.
　基板上にＬＥＤ（発光ダイオード）素子が実装され、蛍光体を含有する透光性の樹脂によりそのＬＥＤ素子が封止された発光装置（ＬＥＤパッケージ）が知られている。こうした発光装置では、ＬＥＤ素子からの光と、ＬＥＤ素子からの光により蛍光体を励起させて得られる光とを混合させることにより、用途に応じて白色光などが得られる。 There is known a light emitting device (LED package) in which an LED (light emitting diode) element is mounted on a substrate and the LED element is sealed with a translucent resin containing a phosphor. In such a light emitting device, white light or the like can be obtained depending on the application by mixing light from the LED element and light obtained by exciting the phosphor with the light from the LED element.
　特許文献１には、発光素子と、その発光素子を配置する凹部を有するパッケージと、蛍光体とフィラーが含有された樹脂とを備える発光装置が記載されている。この発光装置では、比重の大小関係が（蛍光体）＞（フィラー）＞（樹脂）であり、凹部の底面側および発光素子の上面を覆う蛍光体堆積層の上にフィラー堆積層が配置され、凹部の底面側に配置された蛍光体堆積層は発光素子の発光層の高さよりも低く、凹部の底面側に配置された蛍光体堆積層の上に配置されたフィラー堆積層が発光層の側面を被覆している。 Patent Document 1 describes a light-emitting device including a light-emitting element, a package having a recess in which the light-emitting element is disposed, and a resin containing a phosphor and a filler. In this light emitting device, the specific gravity relationship is (phosphor)> (filler)> (resin), and the filler deposition layer is disposed on the phosphor deposition layer covering the bottom surface side of the recess and the top surface of the light emitting element, The phosphor deposited layer disposed on the bottom surface side of the recess is lower than the height of the light emitting layer of the light emitting element, and the filler deposited layer disposed on the phosphor deposited layer disposed on the bottom surface side of the recess is the side surface of the light emitting layer. Is covered.
　特許文献２には、基体と、基体の上面にマウント部を介して実装された発光素子と、発光素子を封止する封止樹脂とを含む発光装置であって、封止樹脂は、マウント部上で発光素子を覆う蛍光体含有第１層と、マウント部の周りの基体上面に形成された蛍光体含有第２層と、マウント部の周りの蛍光体含有第２層上に形成されたフィラー含有層とを有する発光装置が記載されている。 Patent Document 2 discloses a light emitting device that includes a base, a light emitting element mounted on the upper surface of the base via a mount, and a sealing resin that seals the light emitting element. A phosphor-containing first layer covering the light emitting element, a phosphor-containing second layer formed on the upper surface of the substrate around the mount portion, and a filler formed on the phosphor-containing second layer around the mount portion A light emitting device having an inclusion layer is described.
　また、特許文献３には、蛍光体粒子を分散して含有するガラスからなる光変換部材であって、蛍光体粒子の表面に５０％粒径が５０ｎｍ以下のナノフィラーが吸着されており、ガラス中にさらに５０％粒径Ｄ５０が５～３０μｍである耐熱フィラーを分散して含有する光変換部材が記載されている。 Patent Document 3 discloses a light conversion member made of glass containing dispersed phosphor particles, in which nanofillers having a 50% particle size of 50 nm or less are adsorbed on the surface of the phosphor particles. Further, there is described a light conversion member further containing a heat-resistant filler having a 50% particle size D50 of 5 to 30 μm dispersed therein.
特開２０１６－０２６４０４号公報JP 2016-026404 A 国際公開第２０１２／０２９６９５号International Publication No. 2012/029695 特開２０１５－０４６５７９号公報Japanese Patent Laying-Open No. 2015-046579
　封止樹脂内の蛍光体はＬＥＤ素子からの光によって励起されることで発熱するため、封止樹脂内に蛍光体を分散させると、発光時に封止樹脂の温度が上昇し、封止樹脂の寿命およびＬＥＤ素子の発光効率の低下につながる。このため、製造時に封止樹脂内で蛍光体を自然沈降させてから封止樹脂を硬化させることで、蛍光体をＬＥＤ素子の実装基板に近い側に配置して、蛍光体からの熱を実装基板側に放出し易くすることが望ましい。しかしながら、封止樹脂内で蛍光体を完全に沈降させると、実装基板の上面およびＬＥＤ素子の上面には蛍光体が堆積するが、ＬＥＤ素子の側面および角部（斜め上方）には蛍光体層が形成されにくい。この場合、ＬＥＤ素子の斜め上方への出射光に対する蛍光体による波長変換が不十分になるため、その方向ではＬＥＤ素子の発光波長に対応する色が強くなり、発光装置の発光面に色ムラが生じる（すなわち、出射光の色度に角度指向性が生じる）。 Since the phosphor in the sealing resin generates heat when excited by the light from the LED element, if the phosphor is dispersed in the sealing resin, the temperature of the sealing resin increases during light emission, This leads to a decrease in lifetime and light emission efficiency of the LED element. For this reason, the phosphor is naturally settling in the sealing resin during manufacturing and then the sealing resin is cured, so that the phosphor is disposed on the side closer to the mounting substrate of the LED element and the heat from the phosphor is mounted. It is desirable to facilitate release to the substrate side. However, when the phosphor is completely settled in the sealing resin, the phosphor is deposited on the upper surface of the mounting substrate and the upper surface of the LED element, but the phosphor layer is formed on the side surface and corners (obliquely upward) of the LED element. Is difficult to form. In this case, since the wavelength conversion by the phosphor with respect to the light emitted obliquely upward of the LED element becomes insufficient, the color corresponding to the emission wavelength of the LED element becomes strong in that direction, and color unevenness occurs on the light emitting surface of the light emitting device. Occurs (that is, angle directivity occurs in the chromaticity of the emitted light).
　封止樹脂の過熱と発光面の色ムラの両方を防止するためには、封止樹脂内で蛍光体が分散した状態と沈降した状態との中間である「半沈降状態」を実現できるとよい。蛍光体の沈降状態は、発光装置の製造時に、封止樹脂を未硬化の状態に保ったまま例えば数時間放置することで得られるため、原理的には、沈降途中に封止樹脂を硬化させれば半沈降状態になると考えられる。しかしながら、沈降時間を短くして半沈降状態を実現しようとすると、製品ごとのバラつきが大きくなり、安定した生産ができないため、こうした方法をとることは、現実的には難しい。 In order to prevent both the overheating of the sealing resin and the color unevenness of the light emitting surface, it is preferable to realize a “semi-sedimentation state” that is an intermediate between the state in which the phosphor is dispersed and the state in which the phosphor is settled in the sealing resin. . The phosphor settled state is obtained by leaving the sealing resin in an uncured state, for example, for several hours while manufacturing the light emitting device, so in principle, the sealing resin is cured during sedimentation. If so, it is considered to be in a semi-sedimentation state. However, when trying to realize a semi-sedimentation state by shortening the sedimentation time, the variation of each product becomes large, and stable production cannot be performed, so it is practically difficult to take such a method.
　そこで、本発明は、歩留まりを低下させることなく製造でき、ＬＥＤ素子からの光を波長変換する蛍光体が発した熱が実装基板を通じて放出され易く、かつ出射光の色度の角度指向性が生じにくい発光装置を提供することを目的とする。 Therefore, the present invention can be manufactured without reducing the yield, heat generated by the phosphor that converts the wavelength of the light from the LED element is easily emitted through the mounting substrate, and angular directivity of the chromaticity of the emitted light occurs. It is an object to provide a light-emitting device that is difficult.
　実装基板と、実装基板上に実装されたＬＥＤ素子と、ＬＥＤ素子により励起される蛍光体、および平均粒径が１ｎｍ～１００ｎｍの範囲内であるナノフィラーを含有し、ＬＥＤ素子を封止する透光性の封止樹脂とを有し、封止樹脂は、ＬＥＤ素子の上面および側面ならびにＬＥＤ素子の斜め上方を覆うように蛍光体が沈降して形成され、ＬＥＤ素子の形状に沿うように盛り上がった蛍光体の沈降層を有することを特徴とする発光装置が提供される。 A mounting substrate, an LED element mounted on the mounting substrate, a phosphor excited by the LED element, and a nanofiller having an average particle diameter in the range of 1 nm to 100 nm, and a transparent material for sealing the LED element The sealing resin is formed by depositing a phosphor so as to cover the upper surface and side surfaces of the LED element and the oblique upper part of the LED element, and rises along the shape of the LED element. Further, a light emitting device having a sedimented layer of phosphor is provided.
　上記の発光装置では、封止樹脂は、平均粒径が１μｍ～１００μｍの範囲内であるフィラーをさらに含有することが好ましい。 In the above light emitting device, the sealing resin preferably further contains a filler having an average particle diameter in the range of 1 μm to 100 μm.
　上記の発光装置では、封止樹脂は、沈降層の上側に配置され、下方に向かうほど蛍光体をより高い濃度で含有する分散層と、分散層の上側に配置され、蛍光体を分散層よりも低い濃度で含有する樹脂層とをさらに有することが好ましい。 In the above light emitting device, the sealing resin is disposed on the upper side of the sedimentation layer, and is disposed on the upper side of the dispersion layer containing the phosphor in a higher concentration toward the lower side, and the phosphor is disposed above the dispersion layer. It is preferable to further have a resin layer contained at a low concentration.
　上記の発光装置では、実装基板は、周辺部よりも高さが一段高いマウント部を有し、ＬＥＤ素子は、マウント部の上面に実装されていることが好ましい。 In the above light-emitting device, it is preferable that the mounting substrate has a mounting portion that is one step higher than the peripheral portion, and the LED element is mounted on the upper surface of the mounting portion.
　上記の発光装置は、歩留まりを低下させることなく製造でき、ＬＥＤ素子からの光を波長変換する蛍光体が発した熱が実装基板を通じて放出され易く、かつ出射光の色度の角度指向性が生じにくい。 The above light-emitting device can be manufactured without reducing the yield, heat generated by the phosphor that converts the wavelength of light from the LED element is easily emitted through the mounting substrate, and angle directivity of the chromaticity of the emitted light occurs. Hateful.
（Ａ）および（Ｂ）は、発光装置１の断面図および上面図である。(A) And (B) is sectional drawing and the top view of the light-emitting device 1. FIG. （Ａ）および（Ｂ）は、比較例の発光装置１’と発光装置１の断面写真である。(A) And (B) is the cross-sectional photograph of the light-emitting device 1 'and the light-emitting device 1 of a comparative example. （Ａ）～（Ｄ）は、発光装置１，１’の蛍光体層を説明するための模式図である。(A) to (D) are schematic diagrams for explaining the phosphor layers of the light emitting devices 1 and 1 ′. （Ａ）および（Ｂ）は、発光装置２の断面図および上面図である。(A) And (B) is sectional drawing and the top view of the light-emitting device 2. FIG. （Ａ）～（Ｄ）は、発光装置２，２’の蛍光体層を説明するための模式図である。(A) to (D) are schematic diagrams for explaining the phosphor layers of the light emitting devices 2 and 2 ′. （Ａ）～（Ｄ）は、発光装置３，３’の蛍光体層を説明するための模式図である。(A) to (D) are schematic views for explaining the phosphor layers of the light emitting devices 3 and 3 ′. （Ａ）～（Ｃ）は、発光装置１の封止樹脂３０内の一部を示す拡大写真である。(A) to (C) are enlarged photographs showing a part of the sealing resin 30 of the light emitting device 1.
　以下、図面を参照しつつ、発光装置について説明する。ただし、本発明は図面または以下に記載される実施形態には限定されないことを理解されたい。 Hereinafter, the light emitting device will be described with reference to the drawings. However, it should be understood that the present invention is not limited to the drawings or the embodiments described below.
　図１（Ａ）および図１（Ｂ）は、それぞれ発光装置１の断面図および上面図である。発光装置１は、発光素子としてＬＥＤ素子を含み、蛍光体による波長変換を利用して白色光などを出射する発光装置（ＬＥＤパッケージ）であり、例えば各種の照明用のＬＥＤ光源として利用される。発光装置１は、主要な構成要素として、実装基板１０、ＬＥＤ素子２０および封止樹脂３０を有する。なお、ＬＥＤ素子２０の個数は１個に限らず、発光装置は、実装基板１０上に複数のＬＥＤ素子２０が実装されたものであってもよい。 1A and 1B are a cross-sectional view and a top view of the light-emitting device 1, respectively. The light-emitting device 1 is a light-emitting device (LED package) that includes an LED element as a light-emitting element and emits white light or the like using wavelength conversion by a phosphor, and is used as an LED light source for various illuminations, for example. The light emitting device 1 includes a mounting substrate 10, an LED element 20, and a sealing resin 30 as main components. Note that the number of LED elements 20 is not limited to one, and the light emitting device may have a plurality of LED elements 20 mounted on the mounting substrate 10.
　実装基板１０は、ＬＥＤ素子２０を外部電源に接続するための図示しない２つの接続電極を有し、上面にＬＥＤ素子２０が実装される基板である。例えば、実装基板１０は、セラミック基板であってもよいし、耐熱性および放熱性に優れたアルミニウムまたは銅などの金属基板と、ＬＥＤ素子２０の配線パターンおよび接続電極が形成された絶縁性の回路基板とを貼り合わせたものであってもよい。あるいは、実装基板１０は、ＬＥＤ素子２０が実装され封止樹脂３０が充填される凹部を有し、ＬＥＤ素子２０を外部電源に接続するための２つのリード電極が設けられたＬＥＤパッケージの基体であってもよい。 The mounting substrate 10 has two connection electrodes (not shown) for connecting the LED element 20 to an external power supply, and is a substrate on which the LED element 20 is mounted. For example, the mounting substrate 10 may be a ceramic substrate, or an insulating circuit in which a metal substrate such as aluminum or copper excellent in heat resistance and heat dissipation, and a wiring pattern and connection electrodes of the LED element 20 are formed. It may be a laminate of a substrate. Alternatively, the mounting substrate 10 is a base body of an LED package having a recess in which the LED element 20 is mounted and filled with the sealing resin 30, and two lead electrodes for connecting the LED element 20 to an external power source are provided. There may be.
　ＬＥＤ素子２０は、例えば、紫外域から青色領域にわたる波長の光を出射する窒化ガリウム系化合物半導体などで構成された素子である。以下では、ＬＥＤ素子２０は、発光波長帯域が４５０～４６０ｎｍ程度の青色光を発光する青色ＬＥＤ素子であるとして説明するが、ＬＥＤ素子２０は、他の波長の光を出射する素子であってもよい。ＬＥＤ素子２０は実装基板１０の上面にダイボンディングによって実装され、ＬＥＤ素子２０の正負の電極は、２本のボンディングワイヤ２１（以下、単にワイヤ２１という）により、実装基板１０上の接続電極に電気的に接続されている。発光装置が複数のＬＥＤ素子２０を有する場合には、ＬＥＤ素子２０同士もワイヤ２１によって電気的に接続される。なお、ＬＥＤ素子２０の実装方法は、ワイヤボンディングに限らず、フリップチップであってもよい。 The LED element 20 is an element composed of, for example, a gallium nitride compound semiconductor that emits light having a wavelength ranging from the ultraviolet region to the blue region. Hereinafter, the LED element 20 is described as a blue LED element that emits blue light having an emission wavelength band of about 450 to 460 nm. However, the LED element 20 may be an element that emits light of other wavelengths. Good. The LED element 20 is mounted on the upper surface of the mounting substrate 10 by die bonding, and the positive and negative electrodes of the LED element 20 are electrically connected to connection electrodes on the mounting substrate 10 by two bonding wires 21 (hereinafter simply referred to as wires 21). Connected. When the light emitting device has a plurality of LED elements 20, the LED elements 20 are also electrically connected to each other by the wire 21. In addition, the mounting method of the LED element 20 is not limited to wire bonding, and may be flip chip.
　封止樹脂３０は、エポキシ樹脂またはシリコーン樹脂などの透光性の樹脂であり、ＬＥＤ素子２０およびワイヤ２１を一体的に封止する。また、封止樹脂３０は、ＬＥＤ素子２０により励起される蛍光体、フィラーおよびナノフィラーを含有する。発光装置１は、封止樹脂３０の流れ出しを防止するダム材である樹脂製の枠体を有してもよく、その場合、その枠体で囲まれた内側領域に封止樹脂３０を充填してＬＥＤ素子２０およびワイヤ２１を封止してもよい。 The sealing resin 30 is a translucent resin such as an epoxy resin or a silicone resin, and integrally seals the LED element 20 and the wire 21. Moreover, the sealing resin 30 contains a phosphor, a filler, and a nanofiller that are excited by the LED element 20. The light-emitting device 1 may have a resin frame that is a dam material that prevents the sealing resin 30 from flowing out. In that case, the inner region surrounded by the frame is filled with the sealing resin 30. The LED element 20 and the wire 21 may be sealed.
　封止樹脂３０が含有する蛍光体は、１種類でも複数種類でもよい。ＬＥＤ素子２０が青色ＬＥＤである場合には、封止樹脂３０は、例えば、ＹＡＧ（Yttrium Aluminum Garnet）などの黄色蛍光体、およびＣａＡｌＳｉＮ３：Ｅｕ２＋などの赤色蛍光体を含有する。この場合、発光装置１は、ＬＥＤ素子２０からの青色光と、それによって黄色蛍光体および赤色蛍光体を励起させて得られる黄色光および赤色光とを混合させることで得られる白色光を出射する。封止樹脂３０が含有する蛍光体粒子の平均粒径は、例えば、数十μｍ程度である。 The phosphor contained in the sealing resin 30 may be one type or plural types. When the LED element 20 is a blue LED, the sealing resin 30 contains, for example, a yellow phosphor such as YAG (Yttrium Aluminum Garnet) and a red phosphor such as CaAlSiN 3 : Eu 2+ . In this case, the light emitting device 1 emits white light obtained by mixing the blue light from the LED element 20 and the yellow light and red light obtained by exciting the yellow phosphor and the red phosphor thereby. . The average particle diameter of the phosphor particles contained in the sealing resin 30 is, for example, about several tens of μm.
　封止樹脂３０が含有するフィラーは、平均粒径が１μｍ～１００μｍの範囲内であるミクロンサイズの粒子状の無機材料である。フィラーとしては、例えば、二酸化ケイ素（シリカ）、アルミナ、チタニア、ジルコニアまたはマグネシアなどを使用してもよい。フィラーは、封止樹脂３０内で光を拡散させて、ＬＥＤ素子２０および封止樹脂３０で構成される発光装置１の発光領域全体を一様に発光させる散乱材として機能する。 The filler contained in the sealing resin 30 is a micron-sized particulate inorganic material having an average particle diameter in the range of 1 μm to 100 μm. As the filler, for example, silicon dioxide (silica), alumina, titania, zirconia, or magnesia may be used. The filler functions as a scattering material that diffuses light in the sealing resin 30 and uniformly emits light in the entire light emitting region of the light emitting device 1 configured by the LED elements 20 and the sealing resin 30.
　封止樹脂３０が含有するナノフィラーは、平均粒径が１ｎｍ～１００ｎｍの範囲内であるナノサイズの粒子状の無機材料である。フィラーとナノフィラーは、粒径が３桁程度異なるが、同じ物質であってもよい。ナノフィラーとしては、例えば、二酸化ケイ素（シリカ）、アルミナ、チタニア、ジルコニアまたはマグネシアなどを使用してもよい。なお、ナノフィラーは、耐熱性を有し、蛍光体粒子に吸着し易いものであることが好ましい。後述するように、ナノフィラーは、蛍光体粒子の沈降を抑制して、蛍光体粒子の半沈降状態を実現する。 The nanofiller contained in the sealing resin 30 is a nanosized particulate inorganic material having an average particle diameter in the range of 1 nm to 100 nm. The filler and nanofiller differ in particle size by about three orders of magnitude, but may be the same substance. As the nanofiller, for example, silicon dioxide (silica), alumina, titania, zirconia, or magnesia may be used. In addition, it is preferable that a nano filler has heat resistance and is easy to adsorb | suck to a fluorescent substance particle. As will be described later, the nanofiller suppresses the settling of the phosphor particles and realizes a semi-settling state of the phosphor particles.
　発光装置１の製造時には、まず、ＬＥＤ素子２０が実装基板１０の上面にダイボンディングにより固定され、ＬＥＤ素子２０の正負の電極が実装基板１０上の接続電極にワイヤボンディングにより接続される。続いて、ＬＥＤ素子２０の周囲に、上記の蛍光体、フィラーおよびナノフィラーを含有する透光性の封止樹脂３０が充填されて、ＬＥＤ素子２０およびワイヤ２１が封止される。そして、封止樹脂３０を未硬化の状態に保ったまま、例えば数時間かけて封止樹脂３０内の蛍光体とフィラーを実装基板１０およびＬＥＤ素子２０の上面に自然沈降させ、数時間経過後に、例えば加熱により封止樹脂３０を硬化させる。これにより、図１（Ａ）および図１（Ｂ）に示す発光装置１が完成する。 When manufacturing the light emitting device 1, first, the LED element 20 is fixed to the upper surface of the mounting substrate 10 by die bonding, and the positive and negative electrodes of the LED element 20 are connected to the connection electrodes on the mounting substrate 10 by wire bonding. Subsequently, the LED element 20 is filled with the translucent sealing resin 30 containing the phosphor, the filler, and the nanofiller, and the LED element 20 and the wire 21 are sealed. Then, while keeping the sealing resin 30 in an uncured state, for example, the phosphor and filler in the sealing resin 30 are naturally settled on the upper surface of the mounting substrate 10 and the LED element 20 over several hours, and after several hours have passed. For example, the sealing resin 30 is cured by heating. Thereby, the light emitting device 1 shown in FIGS. 1A and 1B is completed.
　図２（Ａ）は比較例の発光装置１’の断面写真であり、図２（Ｂ）は発光装置１の断面写真である。発光装置１’は、封止樹脂以外の点では上記の発光装置１と同じ構成を有する。発光装置１’の封止樹脂３０’は、黄色蛍光体および赤色蛍光体ならびに二酸化ケイ素のフィラーを含有し、ナノフィラーを含有しないシリコーン樹脂である。一方、発光装置１の封止樹脂３０は、黄色蛍光体および赤色蛍光体ならびに二酸化ケイ素のフィラーおよびナノフィラーを含有するシリコーン樹脂である。黄色蛍光体、赤色蛍光体およびフィラーの平均粒径は数μｍ～数十μｍ程度であり、ナノフィラーの平均粒径は数ｎｍ～数十ｎｍ程度である。また、封止樹脂３０におけるナノフィラーの濃度は、０．５ｗｔ％程度である。 FIG. 2A is a cross-sectional photograph of the light-emitting device 1 ′ of the comparative example, and FIG. 2B is a cross-sectional photograph of the light-emitting device 1. The light emitting device 1 ′ has the same configuration as the above light emitting device 1 except for the sealing resin. The sealing resin 30 ′ of the light emitting device 1 ′ is a silicone resin that contains a yellow phosphor, a red phosphor, and a silicon dioxide filler, and does not contain a nanofiller. On the other hand, the sealing resin 30 of the light emitting device 1 is a silicone resin containing a yellow phosphor, a red phosphor, a silicon dioxide filler, and a nanofiller. The average particle size of the yellow phosphor, the red phosphor and the filler is about several μm to several tens of μm, and the average particle size of the nanofiller is about several nm to several tens of nm. Further, the concentration of the nanofiller in the sealing resin 30 is about 0.5 wt%.
　図３（Ａ）～図３（Ｄ）は、発光装置１，１’の蛍光体層を説明するための模式図である。詳細には、図３（Ａ）は、発光装置１’の製造時に、ＬＥＤ素子２０が封止樹脂３０’で封止された直後の断面を示し、図３（Ｂ）は、封止樹脂３０’内の蛍光体が沈降し、完成品となった発光装置１’の断面を示す。同様に、図３（Ｃ）は、発光装置１の製造時に、ＬＥＤ素子２０が封止樹脂３０で封止された直後の断面を示し、図３（Ｄ）は、封止樹脂３０内の蛍光体が沈降し、完成品となった発光装置１の断面を示す。発光装置１，１’は、封止直後は同じ状態であるが、蛍光体の沈降状態が互いに異なる。 FIGS. 3A to 3D are schematic diagrams for explaining the phosphor layers of the light emitting devices 1 and 1 ′. Specifically, FIG. 3A shows a cross section immediately after the LED element 20 is sealed with the sealing resin 30 ′ during the manufacture of the light emitting device 1 ′, and FIG. The cross section of the light-emitting device 1 ′ in which the phosphor inside is settled and becomes a finished product is shown. Similarly, FIG. 3C shows a cross section immediately after the LED element 20 is sealed with the sealing resin 30 during the manufacture of the light emitting device 1, and FIG. 3D shows the fluorescence in the sealing resin 30. The cross section of the light-emitting device 1 which a body settled and became a finished product is shown. The light emitting devices 1 and 1 ′ are in the same state immediately after sealing, but the settling states of the phosphors are different from each other.
　図２（Ａ）および図３（Ｂ）に示すように、発光装置１’では、封止樹脂３０’内の黄色蛍光体、赤色蛍光体およびフィラーの粒子は、実装基板１０の上面およびＬＥＤ素子２０の上面に沈降している。より詳細には、発光装置１’では、実装基板１０の上面およびＬＥＤ素子２０の上面に、黄色蛍光体および赤色蛍光体の沈降層３１’が形成され、その上は、蛍光体粒子を実質的に含有しない樹脂層３３’になっている。沈降層３１’は、主に黄色蛍光体を含む層と、主に赤色蛍光体を含む層とに分かれている。発光装置１’では、図３（Ｂ）に破線３４で示したＬＥＤ素子２０の上面の角部（斜め上方）には、蛍光体の沈降層が形成されていない。 As shown in FIGS. 2A and 3B, in the light emitting device 1 ′, the yellow phosphor, the red phosphor, and the filler particles in the sealing resin 30 ′ are formed on the upper surface of the mounting substrate 10 and the LED element. It has settled on the upper surface of 20. More specifically, in the light emitting device 1 ′, a yellow phosphor and a red phosphor sedimentation layer 31 ′ are formed on the upper surface of the mounting substrate 10 and the upper surface of the LED element 20. The resin layer 33 ′ is not contained in the resin layer 33 ′. The sedimentation layer 31 'is divided into a layer mainly containing a yellow phosphor and a layer mainly containing a red phosphor. In the light emitting device 1 ′, no phosphor sedimentation layer is formed at the corner (obliquely upward) of the upper surface of the LED element 20 indicated by a broken line 34 in FIG.
　一方、図２（Ｂ）および図３（Ｄ）に示すように、発光装置１では、封止樹脂３０内の黄色蛍光体および赤色蛍光体は、一様に分散した状態と完全に沈降した状態との中間である半沈降状態になっている。より詳細には、発光装置１の封止樹脂３０は、黄色蛍光体、赤色蛍光体およびフィラーの沈降層３１と、沈降層３１の上側に配置され、下方に向かうほどこれらの蛍光体をより高い濃度で含有する分散層３２と、分散層３２の上側に配置され、蛍光体粒子を実質的に含有しない樹脂層３３とを有する。樹脂層３３内にも蛍光体粒子は多少存在し得るが、樹脂層３３の蛍光体の濃度は、分散層３２（の上端）の蛍光体の濃度よりも低い。 On the other hand, as shown in FIG. 2 (B) and FIG. 3 (D), in the light emitting device 1, the yellow phosphor and the red phosphor in the sealing resin 30 are uniformly dispersed and completely settled. It is in a semi-sedimentation state that is in between. More specifically, the sealing resin 30 of the light-emitting device 1 is disposed on the sedimentary layer 31 of the yellow phosphor, the red phosphor and the filler, and on the sedimentary layer 31, and these phosphors are higher as they go downward. It has the dispersion layer 32 contained at a concentration, and the resin layer 33 that is disposed on the upper side of the dispersion layer 32 and substantially does not contain phosphor particles. Although some phosphor particles may exist in the resin layer 33, the concentration of the phosphor in the resin layer 33 is lower than the concentration of the phosphor in the dispersion layer 32 (the upper end thereof).
　なお、沈降層３１と分散層３２の境界、および分散層３２と樹脂層３３の境界は、実際には明確に規定されないこともあるが、図３（Ｄ）では便宜的に破線で示している。また、図示した例とは異なり、封止樹脂３０の上端まで蛍光体粒子が存在し、封止樹脂３０は沈降層３１と分散層３２だけで構成されていてもよいが、封止樹脂３０の上端における蛍光体の濃度は０に近いことが好ましい。 Note that the boundary between the sedimentation layer 31 and the dispersion layer 32 and the boundary between the dispersion layer 32 and the resin layer 33 may not be clearly defined in practice, but are shown by broken lines in FIG. 3D for convenience. . Further, unlike the illustrated example, the phosphor particles exist up to the upper end of the sealing resin 30, and the sealing resin 30 may be composed of only the sedimentation layer 31 and the dispersion layer 32. The phosphor concentration at the upper end is preferably close to zero.
　発光装置１では、ＬＥＤ素子２０の上面および側面ならびにＬＥＤ素子２０の斜め上方を覆うように蛍光体が沈降し、図３（Ｄ）に破線３４で示したＬＥＤ素子２０の上面の角部にも蛍光体の沈降層３１が形成されている。沈降層３１は、図１（Ｂ）に示すように、ＬＥＤ素子２０の前後左右のどの方向にも図３（Ｄ）に示したものと同様に広がり、ＬＥＤ素子２０の４方の側面、上面、および斜め上方（上面の４方の周囲）を等方的に覆っている。発光装置１の沈降層３１は、発光装置１’の沈降層３１’とは異なり、ＬＥＤ素子２０の形状に沿うように盛り上がった一続きの層になっている。 In the light emitting device 1, the phosphor settles so as to cover the upper surface and side surfaces of the LED element 20 and the diagonally upper portion of the LED element 20, and also on the corner portion of the upper surface of the LED element 20 indicated by the broken line 34 in FIG. A fluorescent sedimentation layer 31 is formed. As shown in FIG. 1 (B), the sedimentation layer 31 extends in the same direction as that shown in FIG. , And diagonally above (around the top four sides) isotropically. Unlike the sedimented layer 31 ′ of the light emitting device 1 ′, the sedimented layer 31 of the light emitting device 1 is a continuous layer that rises along the shape of the LED element 20.
　封止樹脂３０としてシリコーン樹脂を、フィラーおよびナノフィラーとして二酸化ケイ素を使用する場合には、封止樹脂３０内のナノフィラーの濃度が０．４～０．５ｗｔ％程度であれば、封止樹脂３０を未硬化に保ったまま十分長い時間が経過すると、図２（Ｂ）および図３（Ｄ）に示した半沈降状態が得られる。この半沈降状態では、一部の蛍光体粒子が封止樹脂中に分散したままであり、時間が経過しても完全な沈降状態にはならない。 When silicone resin is used as the sealing resin 30 and silicon dioxide is used as the filler and nanofiller, the sealing resin can be used if the concentration of the nanofiller in the sealing resin 30 is about 0.4 to 0.5 wt%. When a sufficiently long time has passed while keeping 30 uncured, the semi-sedimentation state shown in FIGS. 2 (B) and 3 (D) is obtained. In this semi-sedimentation state, some phosphor particles remain dispersed in the sealing resin and do not become a complete sedimentation state even after a lapse of time.
　一方、封止樹脂３０内がナノフィラーを含有しても、その濃度が０．２ｗｔ％以下であると、図２（Ａ）および図３（Ｂ）に示した発光装置１’と同じ沈降状態になる。また、封止樹脂３０内のナノフィラーの濃度が０．５ｗｔ％を超えると、十分長い時間が経過しても蛍光体は十分に沈降せず、図３（Ｃ）に示したものに近い分散状態が維持される。封止樹脂３０内のナノフィラーの濃度が高いほど、蛍光体は沈降しにくくなる。 On the other hand, even if the sealing resin 30 contains nano filler, if the concentration is 0.2 wt% or less, the same sedimentation state as the light emitting device 1 ′ shown in FIG. 2 (A) and FIG. 3 (B) become. Further, when the concentration of the nanofiller in the sealing resin 30 exceeds 0.5 wt%, the phosphor does not settle sufficiently even after a sufficiently long time, and the dispersion is close to that shown in FIG. State is maintained. The higher the concentration of the nanofiller in the sealing resin 30, the more difficult it is for the phosphor to settle.
　蛍光体が封止樹脂３０内に分散したままであると、上記の通り、発光時に封止樹脂３０の温度が上がり過ぎるおそれがある。封止樹脂３０としてシリコーン樹脂を、フィラーおよびナノフィラーとして二酸化ケイ素を使用する場合には、封止樹脂３０の耐熱温度との関係から、使用可能なナノフィラーの量の上限は、０．５ｗｔ％程度になる。この上限値は、封止樹脂およびナノフィラーの材質によって決まる値である。 If the phosphor remains dispersed in the sealing resin 30, as described above, the temperature of the sealing resin 30 may increase excessively during light emission. When silicone resin is used as the sealing resin 30 and silicon dioxide is used as the filler and nanofiller, the upper limit of the amount of nanofiller that can be used is 0.5 wt% from the relationship with the heat resistance temperature of the sealing resin 30. It will be about. This upper limit is a value determined by the materials of the sealing resin and the nanofiller.
　なお、蛍光体を沈降しにくくする目的で封止樹脂３０として高粘度の樹脂を使用しても、粘度に応じて沈降時間が長くなるだけであり、最終的には、図２（Ａ）および図３（Ｂ）に示した沈降状態になる。図２（Ｂ）および図３（Ｄ）に示した半沈降状態を得るためには、粒径がナノサイズであるナノフィラーを封止樹脂３０に含有させる必要がある。 Note that even if a high-viscosity resin is used as the sealing resin 30 for the purpose of making the phosphor difficult to settle, the sedimentation time only becomes longer depending on the viscosity. The sedimentation state shown in FIG. In order to obtain the semi-sedimentation state shown in FIG. 2B and FIG. 3D, it is necessary to make the sealing resin 30 contain a nanofiller having a nano particle size.
　発光装置１のように、蛍光体、フィラーおよびナノフィラーを含有する封止樹脂３０を用いると、蛍光体はある程度沈降するが、完全沈降にはならず、ＬＥＤ素子２０の角部にも蛍光体層を形成することができる。封止樹脂３０に蛍光体とミクロンサイズのフィラーを含有させるだけでは蛍光体は完全沈降してしまうが、さらにナノフィラーを一定量追加することで、蛍光体を「ふんわりと」沈殿させることが可能になる。ナノフィラーを一定量含有すれば、蛍光体の種類や濃度を変えても、また、フィラーの種類や濃度を変えても、図２（Ｂ）および図３（Ｄ）に示した半沈降状態は維持される。なお、上記の通り、フィラーは主に散乱材として機能するものであるため、蛍光体粒子の半沈降状態を実現するためには、封止樹脂３０は必ずしもフィラーを含有しなくてもよい。 When the sealing resin 30 containing a phosphor, a filler, and a nanofiller is used as in the light emitting device 1, the phosphor settles to some extent, but does not become completely settled, and the phosphor is also present at the corner of the LED element 20. A layer can be formed. Simply adding phosphor and micron-sized filler to the sealing resin 30 will cause the phosphor to settle completely, but adding a certain amount of nanofiller will allow the phosphor to be "softly" precipitated. become. If the nanofiller is contained in a certain amount, the semi-sedimentation state shown in FIG. 2 (B) and FIG. 3 (D) can be obtained regardless of whether the type or concentration of the phosphor is changed or the type or concentration of the filler is changed. Maintained. As described above, since the filler mainly functions as a scattering material, the sealing resin 30 does not necessarily contain a filler in order to realize a semi-sediment state of the phosphor particles.
　図７（Ａ）～図７（Ｃ）は、発光装置１の封止樹脂３０内の一部を示す拡大写真である。図７（Ａ）～図７（Ｃ）の写真は、それぞれ、２千倍、３千倍、２万倍の倍率で撮影されたものであり、各写真の下端に示す白色の線の長さが、それぞれ、１０μｍ、１μｍ、１μｍに相当する。図７（Ｂ）は図７（Ａ）の一部を、図７（Ｃ）は図７（Ｂ）の一部を、それぞれ拡大したものに相当する。 7 (A) to 7 (C) are enlarged photographs showing a part of the sealing resin 30 of the light emitting device 1. The photographs in FIGS. 7A to 7C were taken at a magnification of 2,000, 3,000, and 20,000 times, respectively, and the length of the white line shown at the bottom of each photograph. Correspond to 10 μm, 1 μm, and 1 μm, respectively. 7B corresponds to a part of FIG. 7A and FIG. 7C corresponds to an enlarged part of FIG. 7B.
　図７（Ａ）における符号５１～５３は、それぞれ、赤色蛍光体、黄色蛍光体およびフィラーの粒子であり、図７（Ａ）では、封止樹脂３０内に混入しているミクロンサイズの粒子が見られる。一方、ナノフィラーについては、蛍光体やフィラーよりも粒径が３桁程度小さいため、図７（Ａ）では粒子そのものは見えないが、多数の粒子が集まって凝集体を形成しており、図７（Ａ）に符号５４で示す縞模様がその凝集体に相当する。ナノフィラーの濃度がある程度高ければ、その凝集体によって、図７（Ｂ）および図７（Ｃ）に拡大して示すように、封止樹脂３０内で網目のように入り組んだ層構造（網目構造）が形成される。このため、比重が軽い蛍光体粒子は、その網目構造によって封止樹脂３０内に保持されるので、時間が経過しても下方に沈降しにくくなると考えられる。 Reference numerals 51 to 53 in FIG. 7A denote red phosphor, yellow phosphor and filler particles, respectively. In FIG. 7A, micron-sized particles mixed in the sealing resin 30 are shown. It can be seen. On the other hand, since the particle size of the nanofiller is about three orders of magnitude smaller than that of the phosphor or filler, the particle itself is not visible in FIG. 7A, but a large number of particles gather to form an aggregate. A striped pattern indicated by reference numeral 54 in FIG. If the concentration of the nanofiller is high to some extent, a layer structure (mesh structure) that is intertwined like a mesh in the sealing resin 30 due to the aggregate, as shown in an enlarged view in FIGS. ) Is formed. For this reason, since the phosphor particles having a low specific gravity are held in the sealing resin 30 by the network structure, it is considered that the phosphor particles are less likely to settle downward even after a lapse of time.
　発光装置１では、蛍光体が完全沈降せず、ＬＥＤ素子２０の角部も含めて一定の厚みの蛍光体層が形成されるので、ＬＥＤ素子２０の斜め上方への出射光も、他の方向への出射光と同様に封止樹脂３０内の蛍光体によって波長変換される。したがって、発光装置１では、出射光の色度に角度指向性が生じにくくなるので、発光面の色ムラが生じにくい。また、発光装置１では、半沈降状態が実現され、蛍光体粒子が実装基板１０に近い側に配置されているため、蛍光体からの熱は実装基板１０側に放出され易く、封止樹脂３０の過熱も生じにくい。また、封止樹脂３０内のナノフィラーの濃度を同じにすれば最終的には同じ半沈降状態が得られるため、発光装置１では、ナノフィラーを用いずに沈降途中で封止樹脂を硬化させる場合と比べて、製品ごとの色度のバラつきは小さくなり、歩留まりも向上する。 In the light emitting device 1, the phosphor is not completely settled, and a phosphor layer having a constant thickness including the corners of the LED element 20 is formed. The wavelength is converted by the phosphor in the sealing resin 30 in the same manner as the light emitted to the. Accordingly, in the light emitting device 1, angle directivity is hardly generated in the chromaticity of the emitted light, and thus color unevenness on the light emitting surface is hardly generated. In the light emitting device 1, the semi-sediment state is realized, and the phosphor particles are arranged on the side close to the mounting substrate 10. Therefore, heat from the phosphor is easily released to the mounting substrate 10 side, and the sealing resin 30. It is also difficult to overheat. Moreover, since the same semi-sedimentation state is finally obtained if the concentration of the nanofiller in the sealing resin 30 is the same, the light-emitting device 1 cures the sealing resin during the precipitation without using the nanofiller. Compared to the case, the variation in chromaticity for each product is reduced, and the yield is improved.
　図４（Ａ）および図４（Ｂ）は、それぞれ、発光装置２の断面図および上面図である。発光装置２は、実装基板以外の点では上記の発光装置１と同じ構成を有する。発光装置２の実装基板１０’は、周辺部１２よりも高さが一段高いマウント部１１を有し、ＬＥＤ素子２０はマウント部１１の上面に実装されている。言い換えると、発光装置２では、実装基板１０’上でＬＥＤ素子２０が実装されるマウント部１１の周辺部１２は、マウント部１１よりも一段低い凹部になっている。周辺部１２に対するマウント部１１の高さは、ＬＥＤ素子２０の高さと同程度であることが好ましい。なお、マウント部１１は、実装基板１０’と一体で構成されていてもよいし、実装基板１０’とは別体のものが実装基板１０’に取り付けられていてもよい。また、発光装置２でも、ＬＥＤ素子２０の個数は１個に限らず、複数であってもよい。 4A and 4B are a cross-sectional view and a top view of the light-emitting device 2, respectively. The light emitting device 2 has the same configuration as the above light emitting device 1 except for the mounting substrate. The mounting substrate 10 ′ of the light emitting device 2 has a mount portion 11 that is one step higher than the peripheral portion 12, and the LED element 20 is mounted on the upper surface of the mount portion 11. In other words, in the light emitting device 2, the peripheral portion 12 of the mount portion 11 on which the LED element 20 is mounted on the mounting substrate 10 ′ is a recess that is one step lower than the mount portion 11. The height of the mount portion 11 with respect to the peripheral portion 12 is preferably approximately the same as the height of the LED element 20. The mount portion 11 may be configured integrally with the mounting substrate 10 ′, or a separate member from the mounting substrate 10 ′ may be attached to the mounting substrate 10 ′. In the light emitting device 2, the number of LED elements 20 is not limited to one and may be plural.
　図５（Ａ）～図５（Ｄ）は、発光装置２，２’の蛍光体層を説明するための模式図である。発光装置２’は、封止樹脂以外の点では上記の発光装置２と同じ構成を有する。発光装置２’の封止樹脂４０’は、発光装置１’の封止樹脂３０’と同様に、黄色蛍光体、赤色蛍光体およびフィラーを含有するが、ナノフィラーを含有しない。一方、発光装置２の封止樹脂４０は、黄色蛍光体、赤色蛍光体、フィラーおよびナノフィラーを含有する。図５（Ａ）は、発光装置２’の製造時に、ＬＥＤ素子２０が封止樹脂４０’で封止された直後の断面を示し、図５（Ｂ）は、封止樹脂４０’内の蛍光体が沈降し、完成品となった発光装置２’の断面を示す。同様に、図５（Ｃ）は、発光装置２の製造時に、ＬＥＤ素子２０が封止樹脂４０で封止された直後の断面を示し、図５（Ｄ）は、封止樹脂４０内の蛍光体が沈降し、完成品となった発光装置２の断面を示す。 FIGS. 5A to 5D are schematic views for explaining the phosphor layers of the light emitting devices 2 and 2 ′. The light emitting device 2 ′ has the same configuration as the light emitting device 2 described above except for the sealing resin. The sealing resin 40 ′ of the light emitting device 2 ′ contains a yellow phosphor, a red phosphor and a filler, but does not contain a nanofiller, like the sealing resin 30 ′ of the light emitting device 1 ′. On the other hand, the sealing resin 40 of the light emitting device 2 contains a yellow phosphor, a red phosphor, a filler, and a nanofiller. FIG. 5A shows a cross section immediately after the LED element 20 is sealed with the sealing resin 40 ′ during the manufacture of the light emitting device 2 ′, and FIG. 5B shows the fluorescence in the sealing resin 40 ′. The cross section of the light-emitting device 2 ′ in which the body has settled and becomes a finished product is shown. Similarly, FIG. 5C shows a cross section immediately after the LED element 20 is sealed with the sealing resin 40 at the time of manufacturing the light emitting device 2, and FIG. 5D shows the fluorescence in the sealing resin 40. The cross section of the light-emitting device 2 which the body settled and became a finished product is shown.
　図５（Ｂ）に示すように、発光装置２’では、実装基板１０’のマウント部１１および周辺部１２の上面、ならびにＬＥＤ素子２０の上面に、黄色蛍光体および赤色蛍光体の沈降層４１’が形成されている。沈降層４１’は、主に黄色蛍光体を含む層と、主に赤色蛍光体を含む層とに分かれている。沈降層４１’の上は、蛍光体粒子を実質的に含有しない樹脂層４３’になっている。発光装置２’では、図５（Ｂ）に破線４４で示したＬＥＤ素子２０の上面の角部（斜め上方）には、蛍光体の沈降層が形成されていない。 As shown in FIG. 5B, in the light emitting device 2 ′, a yellow phosphor and a red phosphor sedimentation layer 41 are formed on the upper surface of the mount portion 11 and the peripheral portion 12 of the mounting substrate 10 ′ and the upper surface of the LED element 20. 'Is formed. The sedimentation layer 41 ′ is divided into a layer mainly containing a yellow phosphor and a layer mainly containing a red phosphor. Above the sedimentation layer 41 'is a resin layer 43' that does not substantially contain phosphor particles. In the light emitting device 2 ′, no phosphor sedimentation layer is formed at the corner (obliquely upward) of the upper surface of the LED element 20 indicated by a broken line 44 in FIG.
　一方、図５（Ｄ）に示すように、発光装置２の封止樹脂４０は、発光装置１の沈降層３１、分散層３２および樹脂層３３と同様の沈降層４１、分散層４２および樹脂層４３を有する。発光装置２でも、ＬＥＤ素子２０の上面および側面ならびにＬＥＤ素子２０の斜め上方を覆うように蛍光体が沈降し、図５（Ｄ）に破線４４で示したＬＥＤ素子２０の上面の角部にも、蛍光体の沈降層４１が形成されている。沈降層４１も、ＬＥＤ素子２０の４方の側面、上面、および斜め上方（上面の４方の周囲）を等方的に覆っている。 On the other hand, as shown in FIG. 5D, the sealing resin 40 of the light emitting device 2 includes a sedimented layer 41, a dispersed layer 42, and a resin layer similar to the sedimented layer 31, the dispersed layer 32, and the resin layer 33 of the light emitting device 1. 43. Also in the light emitting device 2, the phosphor settles so as to cover the upper surface and side surfaces of the LED element 20 and the diagonally upper portion of the LED element 20, and also on the corner portion of the upper surface of the LED element 20 indicated by the broken line 44 in FIG. A sedimentation layer 41 of phosphor is formed. The sedimentation layer 41 also isotropically covers the four side surfaces, the top surface, and the diagonally upper side (around the four top surfaces) of the LED element 20.
　発光装置２でも、封止樹脂４０がナノフィラーを含有することで、蛍光体が完全沈降せず、ＬＥＤ素子２０の角部も含めて一定の厚みの蛍光体層が形成されるため、出射光の色度に角度指向性が生じにくくなり、発光面の色ムラが生じにくい。また、発光装置２でも、発光装置１と同様に、蛍光体からの熱は実装基板１０’側に放出され易く、ナノフィラーを用いずに沈降途中で封止樹脂を硬化させて半沈降状態を実現する場合と比べて、製品の歩留まりも向上する。 Also in the light emitting device 2, since the sealing resin 40 contains the nano filler, the phosphor does not completely settle, and a phosphor layer having a certain thickness including the corners of the LED element 20 is formed. The angle directivity is less likely to occur in the chromaticity, and the color unevenness of the light emitting surface is less likely to occur. Further, in the light emitting device 2, similarly to the light emitting device 1, the heat from the phosphor is easily released to the mounting substrate 10 ′ side, and the sealing resin is cured in the middle of the precipitation without using the nanofiller, so that the semi-sedimented state is obtained. Compared to realization, the product yield is also improved.
　発光装置１では、図３（Ｄ）に示したように、ＬＥＤ素子２０の側方が沈降層３１に埋まっているので、ＬＥＤ素子２０から側方に出射された光は、上方への出射光と比べて、蛍光体層をより長く通過する。一方、発光装置２では、ＬＥＤ素子２０が実装されるマウント部１１と比べて周辺部１２が低い位置にあるため、周辺部１２に沈降した蛍光体は、発光装置１の場合よりも、ＬＥＤ素子２０に対して低い位置にある。これにより、発光装置２では、ＬＥＤ素子２０の側方、斜め上方および上方における沈降層４１の厚さがほぼ均一になるため、光の出射方向によらず、ほぼ均一に波長変換が行われる。したがって、発光装置２では、発光装置１と比べてさらに発光面の色ムラが生じにくい。また、発光装置２では、特に複数のＬＥＤ素子２０を有する場合に、ＬＥＤ素子２０同士の間に無駄な蛍光体層ができないため、発光装置１と比べて光の取出し効率も高くなる。 In the light emitting device 1, as shown in FIG. 3D, since the side of the LED element 20 is buried in the sedimentation layer 31, the light emitted from the LED element 20 to the side is emitted light upward. Compared with, it passes through the phosphor layer longer. On the other hand, in the light emitting device 2, since the peripheral portion 12 is at a lower position than the mount portion 11 on which the LED element 20 is mounted, the phosphor settled on the peripheral portion 12 is more LED element than in the light emitting device 1. It is in a lower position with respect to 20. Thereby, in the light emitting device 2, since the thickness of the sedimentation layer 41 on the side of the LED element 20, obliquely above and above is substantially uniform, wavelength conversion is performed almost uniformly regardless of the light emission direction. Therefore, the light emitting device 2 is less likely to cause color unevenness on the light emitting surface as compared to the light emitting device 1. In addition, in the light emitting device 2, in particular, when a plurality of LED elements 20 are provided, a useless phosphor layer is not formed between the LED elements 20, so that the light extraction efficiency is higher than that of the light emitting device 1.
　図６（Ａ）～図６（Ｄ）は、発光装置３，３’の蛍光体層を説明するための模式図である。発光装置３，３’は、それぞれ、封止樹脂７０，７０’が含有する蛍光体が黄色蛍光体の１種類のみである点を除いて、上記の発光装置１，１’と同じ構成を有する。図６（Ａ）～図６（Ｄ）は、それぞれ、図３（Ａ）～図３（Ｄ）と同じ状態を示す図である。発光装置３の封止樹脂７０は、黄色蛍光体、フィラーおよびナノフィラーを含有し、発光装置３’の封止樹脂７０’は、黄色蛍光体およびフィラーを含有する。 6 (A) to 6 (D) are schematic diagrams for explaining the phosphor layers of the light emitting devices 3 and 3 '. The light emitting devices 3 and 3 ′ have the same configuration as the above light emitting devices 1 and 1 ′, except that the phosphors contained in the sealing resins 70 and 70 ′ are only one kind of yellow phosphor. . FIGS. 6A to 6D are views showing the same states as FIGS. 3A to 3D, respectively. The sealing resin 70 of the light emitting device 3 contains a yellow phosphor, a filler, and a nano filler, and the sealing resin 70 'of the light emitting device 3' contains a yellow phosphor and a filler.
　図６（Ｂ）に示す封止樹脂７０’内の沈降層７１’および樹脂層７３’は、沈降層７１’が蛍光体の種類ごとの複数層に分かれていない点を除いて、図３（Ｂ）の沈降層３１’および樹脂層３３’と同様のものである。ナノフィラーがない封止樹脂７０’内では、蛍光体粒子が完全に沈降するため、破線７４で示したＬＥＤ素子２０の上面の角部（ＬＥＤ素子２０の発光層２２の側方）には沈降層７１’がなく、発光層２２は樹脂層７３’内で露出している。 The sedimentation layer 71 ′ and the resin layer 73 ′ in the sealing resin 70 ′ shown in FIG. 6B are the same as those in FIG. 3 except that the sedimentation layer 71 ′ is not divided into a plurality of layers for each phosphor type. It is the same as the sedimentation layer 31 ′ and the resin layer 33 ′ of B). In the sealing resin 70 ′ having no nano filler, the phosphor particles are completely settled, and thus settled at the corner of the upper surface of the LED element 20 (side of the light emitting layer 22 of the LED element 20) indicated by the broken line 74. There is no layer 71 ′, and the light emitting layer 22 is exposed in the resin layer 73 ′.
　図６（Ｄ）に示す封止樹脂７０内の沈降層７１、分散層７２および樹脂層７３は、図３（Ｄ）の沈降層３１、分散層３２および樹脂層３３と同様のものである。ナノフィラーがある封止樹脂７０内では、破線７４で示したＬＥＤ素子２０の上面の角部にも蛍光体粒子の沈降層７１が形成され、半沈降状態が実現されている。封止樹脂７０内では、ＬＥＤ素子２０の発光層２２の側方が沈降層７１で覆われており、半沈降状態は、ＬＥＤ素子の発光層が蛍光体粒子の沈降層で覆われた状態であるとも言える。 6 (D), the sedimentation layer 71, the dispersion layer 72, and the resin layer 73 in the sealing resin 70 are the same as the sedimentation layer 31, the dispersion layer 32, and the resin layer 33 in FIG. 3 (D). In the sealing resin 70 with the nano filler, the sedimentation layer 71 of the phosphor particles is also formed at the corner portion of the upper surface of the LED element 20 indicated by the broken line 74, thereby realizing a semi-sedimentation state. In the sealing resin 70, the side of the light emitting layer 22 of the LED element 20 is covered with the sedimented layer 71, and the semi-sedimented state is a state in which the light emitting layer of the LED element is covered with the sedimented layer of phosphor particles. It can be said that there is.
　ＬＥＤ素子２０が青色ＬＥＤである場合には、青色光との組合せで白色光を出射できるように、発光装置の封止樹脂は、蛍光体として黄色蛍光体のみを含有してもよい。この場合、黄色蛍光体として粒径（メジアン径Ｄ５０）が１～３０μｍかつ比重が２～１０ｇ／ｃｍ３のものを使用し、封止樹脂７０（シリコーン樹脂）に対するナノフィラーの濃度を０．２～１．５ｗｔ％の範囲内とすることが好ましい。なお、黄色蛍光体は、ナノフィラーの濃度が０．２ｗｔ％以下であると完全沈降し、ナノフィラーの濃度が１．５ｗｔ％を超えると封止樹脂７０内に分散したままとなる。封止樹脂７０が０．２～１．５ｗｔ％のナノフィラーを含有すれば、半沈降状態が実現されるので、図６（Ｄ）に示す発光装置３でも、発光装置の発光面の色ムラや封止樹脂７０の過熱が生じにくくなる。 When the LED element 20 is a blue LED, the sealing resin of the light emitting device may contain only a yellow phosphor as a phosphor so that white light can be emitted in combination with blue light. In this case, a yellow phosphor having a particle diameter (median diameter D50) of 1 to 30 μm and a specific gravity of 2 to 10 g / cm 3 is used, and the concentration of the nanofiller with respect to the sealing resin 70 (silicone resin) is 0.2. It is preferable to be in the range of ~ 1.5 wt%. The yellow phosphor completely settles when the nanofiller concentration is 0.2 wt% or less, and remains dispersed in the sealing resin 70 when the nanofiller concentration exceeds 1.5 wt%. If the sealing resin 70 contains 0.2 to 1.5 wt% of nanofiller, a semi-sedimentation state is realized. Therefore, even in the light emitting device 3 shown in FIG. 6D, color unevenness on the light emitting surface of the light emitting device. And overheating of the sealing resin 70 is less likely to occur.

Claims (4)

  1. 　実装基板と、
    　前記実装基板上に実装されたＬＥＤ素子と、
    　前記ＬＥＤ素子により励起される蛍光体、および平均粒径が１ｎｍ～１００ｎｍの範囲内であるナノフィラーを含有し、前記ＬＥＤ素子を封止する透光性の封止樹脂と、を有し、
    　前記封止樹脂は、前記ＬＥＤ素子の上面および側面ならびに前記ＬＥＤ素子の斜め上方を覆うように前記蛍光体が沈降して形成され、前記ＬＥＤ素子の形状に沿うように盛り上がった前記蛍光体の沈降層を有する、
    　ことを特徴とする発光装置。     A mounting board;
    LED elements mounted on the mounting substrate;
    A phosphor excited by the LED element, and a nanofiller having an average particle diameter in the range of 1 nm to 100 nm, and a translucent sealing resin that seals the LED element,
    The sealing resin is formed by sinking the phosphor so as to cover an upper surface and a side surface of the LED element and an obliquely upper part of the LED element, and sinking the phosphor that rises along the shape of the LED element. Having a layer,
    A light emitting device characterized by that.
  2. 　前記封止樹脂は、平均粒径が１μｍ～１００μｍの範囲内であるフィラーをさらに含有する、請求項１に記載の発光装置。 2. The light emitting device according to claim 1, wherein the sealing resin further contains a filler having an average particle diameter in the range of 1 μm to 100 μm.
  3. 　前記封止樹脂は、
    　　前記沈降層の上側に配置され、下方に向かうほど前記蛍光体をより高い濃度で含有する分散層と、
    　　前記分散層の上側に配置され、前記蛍光体を前記分散層よりも低い濃度で含有する樹脂層と、
    　をさらに有する、請求項１または２に記載の発光装置。     The sealing resin is
    A dispersion layer that is disposed on the upper side of the sedimentation layer and contains the phosphor in a higher concentration toward the lower side;
    A resin layer disposed on the upper side of the dispersion layer and containing the phosphor at a lower concentration than the dispersion layer;
    The light emitting device according to claim 1, further comprising:
  4. 　前記実装基板は、周辺部よりも高さが一段高いマウント部を有し、
    　前記ＬＥＤ素子は、前記マウント部の上面に実装されている、請求項３に記載の発光装置。     The mounting substrate has a mount part that is one step higher than the peripheral part,
    The light emitting device according to claim 3, wherein the LED element is mounted on an upper surface of the mount portion.
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10825949B2 (en) 2018-08-27 2020-11-03 Nichia Corporation Method of manufacturing light emitting device

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2005277127A (en) * 2004-03-25 2005-10-06 Stanley Electric Co Ltd Light-emitting device
JP2011233870A (en) * 2010-04-09 2011-11-17 Mitsubishi Chemicals Corp Semiconductor light-emitting device
JP2014031436A (en) * 2012-08-03 2014-02-20 Shin Etsu Chem Co Ltd Curable resin composition, cured product of the same, and optical semiconductor device using the cured product
JP2016026404A (en) * 2010-11-05 2016-02-12 日亜化学工業株式会社 Light-emitting device and method for manufacturing the same
JP2016063001A (en) * 2014-09-16 2016-04-25 日亜化学工業株式会社 Light-emitting device
JP2016082212A (en) * 2014-10-17 2016-05-16 日亜化学工業株式会社 Light-emitting device and resin composition

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2005277127A (en) * 2004-03-25 2005-10-06 Stanley Electric Co Ltd Light-emitting device
JP2011233870A (en) * 2010-04-09 2011-11-17 Mitsubishi Chemicals Corp Semiconductor light-emitting device
JP2016026404A (en) * 2010-11-05 2016-02-12 日亜化学工業株式会社 Light-emitting device and method for manufacturing the same
JP2014031436A (en) * 2012-08-03 2014-02-20 Shin Etsu Chem Co Ltd Curable resin composition, cured product of the same, and optical semiconductor device using the cured product
JP2016063001A (en) * 2014-09-16 2016-04-25 日亜化学工業株式会社 Light-emitting device
JP2016082212A (en) * 2014-10-17 2016-05-16 日亜化学工業株式会社 Light-emitting device and resin composition

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10825949B2 (en) 2018-08-27 2020-11-03 Nichia Corporation Method of manufacturing light emitting device

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