JP2013098458A - Semiconductor light-emitting device and illumination instrument employing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor light-emitting device in which desired combination light can be supplied and costs can be reduced easily, and an illumination instrument employing the same.SOLUTION: A semiconductor light-emitting device comprises a wiring board, a semiconductor light-emitting element which is disposed on a mount surface of the wiring board and in which the wavelength of a light emission peak is 360 to 480 nm, and a wavelength conversion section which extends so as to cross radiation light emitted by the semiconductor light-emitting element and performs wavelength conversion on at least a part of the radiation light. The wavelength conversion section is divided in an extension direction of the wavelength conversion section into a first wavelength conversion region which includes an organic phosphor and a light scattering material and in which average transmissivity of the radiation light emitted by the semiconductor light-emitting element is 20% or less, and a second wavelength conversion region which includes an inorganic phosphor.

Description

  The present invention relates to a semiconductor light emitting device using an LED chip that emits light in a predetermined wavelength range, and a wavelength conversion member that converts the wavelength of light emitted from the LED chip, and a lighting fixture using the semiconductor light emitting device.

  Incandescent light bulbs and fluorescent lamps have been widely used as light sources for light emitting devices. In recent years, in addition to these, semiconductor light-emitting devices using a semiconductor light-emitting element such as a light-emitting diode (LED) or an organic EL (OLED) as a light source have been developed and used. Since these semiconductor light emitting elements can obtain various emission colors, a plurality of semiconductor light emitting elements having different emission colors are combined, and the respective emission colors are combined to obtain a combined light of a desired color. Such semiconductor light emitting devices have been developed and used.

  For example, a red LED using an LED chip whose emission color is red, a green LED using an LED chip whose emission color is green, and a blue LED using an LED chip whose emission color is blue are combined and supplied to each LED. Japanese Patent Application Laid-Open No. 2004-151867 discloses a semiconductor light emitting device that emits desired white light by adjusting the driving current to be synthesized and combining the light emitted from each LED.

  Originally, since the emission spectrum width of the LED chip itself is relatively narrow, when the light emitted from the LED chip itself is used as it is for illumination, there is a problem that the color rendering properties that are important in general illumination light are lowered. Therefore, in order to solve such problems, an LED has been developed in which the light emitted from the LED chip is wavelength-converted by a wavelength conversion member such as a phosphor, and the light obtained by the wavelength conversion is emitted. A semiconductor light emitting device combining LEDs is disclosed in, for example, Patent Document 2.

  In the semiconductor light emitting device of Patent Document 2, in addition to a blue LED using a blue light emitting LED chip, a similar LED chip is combined with a green phosphor that emits green light when excited by light emitted from the LED chip. A green LED and a red LED obtained by combining a similar LED chip with a red phosphor that is excited by light emitted from the LED chip to emit red light are used. Then, by combining the light emitted by each of the blue LED, the green LED, and the red LED, the semiconductor light emitting device can secure the excellent color rendering property to the light emitted from the semiconductor light emitting device and adjust the light output of each LED. The color of the light emitted by can be changed in various ways.

JP 2006-4839 A JP 2007-122950 A

  Conventionally, inorganic phosphors and organic phosphors have been known as materials used for wavelength conversion members. Although organic phosphors are cheaper than inorganic phosphors, they are more transparent than inorganic phosphors, so there is a high probability of transmitting the radiated light from the LED chip as it is, and excitation light is more in comparison with inorganic phosphors. It was also known to be difficult to occur. For this reason, even if a wavelength conversion member made of an organic phosphor is used for a semiconductor light emitting device that emits synthetic light, it is difficult to achieve desired white light characteristics. In many cases, a wavelength conversion member is used.

  However, with the widespread use of lighting fixtures equipped with semiconductor light emitting devices using LED chips, there is a demand for lower costs for lighting fixtures and lower costs for semiconductor light emitting devices. Has not been able to reduce the cost sufficiently.

  The present invention has been made in view of such a problem, and an object of the present invention is to provide a semiconductor light-emitting device capable of supplying desired synthesized light and easily reducing the cost, and the semiconductor light-emitting device A lighting apparatus using the above will be provided.

  In order to achieve the above object, a semiconductor light emitting device of the present invention includes a wiring board, a semiconductor light emitting element disposed on a mounting surface of the wiring board, and having a light emission peak wavelength of 360 nm to 480 nm, and the semiconductor light emitting element. A wavelength converter that extends so as to intersect with the emitted light, and converts the wavelength of at least a part of the emitted light, and the wavelength converter includes an organic phosphor and a light diffusing material, and The first wavelength conversion region where the average transmittance of the emitted light emitted from the semiconductor light emitting element is 20% or less and the second wavelength conversion region including the inorganic phosphor are divided into regions in the extending direction of the wavelength conversion unit. It is characterized by being.

  In the semiconductor light emitting device described above, the concentration of the organic phosphor in the first wavelength conversion region is more preferably 10% by weight or less, and further preferably 0.1% by weight or more and 5.0% by weight or less.

  In the semiconductor light emitting device described above, the wavelength conversion unit may be formed on the surface of the transparent substrate.

  In the semiconductor light emitting device described above, the wavelength conversion unit may be formed by mixing with a light transmissive material.

  In the semiconductor light emitting device described above, the first wavelength conversion region may include an organic phosphor layer made of the organic phosphor and a light diffusion layer made of the light diffusing material. In such a case, the first wavelength conversion region has a laminated structure in which the organic phosphor layer is laminated on the light diffusion layer, and the light diffusion layer is more light emitting than the organic phosphor layer. It may be close to the element.

  In the semiconductor light emitting device described above, the organic phosphor may be composed of a red organic phosphor. In such a case, the red organic phosphor may have a perylene structure or a porphyrin structure.

  In the semiconductor light emitting device described above, the inorganic phosphor may be composed of at least one of a green inorganic phosphor and a yellow inorganic phosphor.

  In the semiconductor light emitting device described above, the wavelength of the emission peak of the semiconductor light emitting element may be 440 nm to 470 nm.

  In the semiconductor light emitting device described above, the content of the light diffusing material in the first wavelength conversion region is more preferably 1.0 wt% or more and 70 wt% or less.

  In the semiconductor light emitting device described above, the light diffusing material may be one or more selected from the group consisting of zinc oxide, titanium oxide, aluminum oxide, silicon oxide, zirconium oxide, calcium carbonate, and boron oxide. Good.

  In the semiconductor light emitting device described above, the film thickness of the first wavelength conversion region is more preferably 10 μm or more.

  In the semiconductor light emitting device described above, the emitted light that has passed through the wavelength conversion unit without being wavelength-converted by the wavelength conversion unit, the first converted light that has been wavelength-converted by the organic phosphor, and the wavelength by the inorganic phosphor White light may be generated by mixing the converted second converted light.

  You may comprise a lighting fixture using the semiconductor light-emitting device mentioned above.

  In the semiconductor light emitting device of the present invention, since the wavelength conversion unit is composed of the first wavelength conversion region including the organic phosphor and the light diffusing material and the second wavelength conversion region including the inorganic phosphor, the LED chip emits light. The converted light is wavelength-converted into light corresponding to each phosphor in each wavelength conversion region.

  Further, in the semiconductor light emitting device of the present invention, the average transmittance of the first wavelength conversion region is 20% or less, so that the light from the LED chip is favorably wavelength-converted to other light according to the organic phosphor. Can do.

  Therefore, with the configuration of the semiconductor light emitting device as described above, desired synthesized light can be easily supplied and cost reduction can be easily achieved.

  In the semiconductor light emitting device described above, the first wavelength conversion region is adjusted by adjusting the concentration of the organic phosphor in the first wavelength conversion region to 10 wt% or less, more preferably from 0.1 wt% to 5.0 wt%. The wavelength conversion efficiency in can be improved, and desired light can be easily emitted by the wavelength conversion.

  In the semiconductor light emitting device described above, by adjusting the content ratio of the light diffusing material in the first wavelength conversion region to 1.0 wt% or more and 70 wt% or less, the light from the LED chip incident on the first wavelength conversion region is adjusted. It can diffuse well. As a result, the light wavelength-converted by the organic phosphor in the first wavelength conversion region increases, and the wavelength conversion efficiency in the first wavelength conversion region is improved. Therefore, desired light can be easily emitted by the wavelength conversion.

  In the semiconductor light emitting device described above, by adjusting the film thickness of the first wavelength conversion region to 10 μm or more, the wavelength conversion efficiency in the first wavelength conversion region is improved, and desired light is easily emitted by the wavelength conversion. Can do.

  By using the above-described semiconductor light-emitting device for a lighting fixture, it becomes possible to supply light of various color temperatures and to manufacture the light at low cost.

1 is a perspective view showing an outline of an overall configuration of a semiconductor light emitting device according to a first embodiment. 1 is a plan view of a semiconductor light emitting device according to a first embodiment. FIG. 3 is a cross-sectional view of the semiconductor light emitting device taken along line III-III in FIG. 2. It is an expanded sectional view of the principal part in FIG. It is an expanded sectional view of the principal part different from FIG. 4 in FIG. It is an electric circuit diagram which shows the outline of the electric circuit structure of the illuminating device using the semiconductor light-emitting device which concerns on 1st Embodiment. It is a top view which shows the 1st modification of the wavelength conversion part of the semiconductor light-emitting device concerning 1st Embodiment. It is a top view which shows the 2nd modification of the wavelength conversion part of the semiconductor light-emitting device concerning 1st Embodiment. It is sectional drawing which shows the 3rd modification of the semiconductor light-emitting device concerning 1st Embodiment. It is sectional drawing which shows the 4th modification of the semiconductor light-emitting device concerning 1st Embodiment. It is an expanded sectional view of the principal part of the semiconductor light-emitting device concerning a 2nd embodiment. It is a schematic block diagram of the 1st wavelength conversion area | region of the semiconductor light-emitting device concerning 2nd Embodiment. It is a perspective view which shows the basic composition of the semiconductor light-emitting device concerning 3rd Embodiment. It is a top view of the semiconductor light-emitting device concerning a 3rd embodiment. It is sectional drawing of the semiconductor light-emitting device which follows the XV-XV line | wire in FIG. It is a graph which shows the relationship between the wavelength of the light radiated | emitted from a wavelength conversion member, and peak intensity. 18 is an emission spectrum of the semiconductor light emitting device according to Example 17;

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail based on some embodiments with reference to the drawings. In addition, this invention is not limited to the content demonstrated below, In the range which does not change the summary, it can change arbitrarily and can implement. The drawings used for describing each embodiment schematically show a semiconductor light emitting device according to the present invention, and are partially emphasized, enlarged, reduced, or omitted to deepen understanding. In some cases, it does not accurately represent the scale or shape of each component. Furthermore, all the various numerical values used in each embodiment show an example, and can be changed variously as necessary.

<First Embodiment>
(Configuration of semiconductor light emitting device)
FIG. 1 is a perspective view schematically showing the overall configuration of the semiconductor light emitting device 1 according to the first embodiment, and FIG. 2 is a plan view of the semiconductor light emitting device 1 of FIG. 1 and 2, the width direction of the semiconductor light emitting device 1 is defined as the X direction, the longitudinal direction is defined as the Y direction, and the height direction is defined as the Z direction. As shown in FIG. 1, the semiconductor light emitting device 1 includes a wiring substrate 2 made of an alumina-based ceramic having excellent electrical insulation and good heat dissipation. On the chip mounting surface 2 a of the wiring board 2, there are a total of 20 semiconductor light emitting elements, four in the width direction (that is, the X direction) and five in the longitudinal direction (that is, the Y direction) at equal intervals. A certain light emitting diode (LED) chip 3 is arranged. Although not shown in FIG. 1, a wiring pattern for supplying electric power to each of these LED chips 3 is formed on the wiring board 2, and constitutes an electric circuit described later.

  Note that the material of the wiring board 2 is not limited to alumina-based ceramics. For example, a material selected from resin, glass epoxy, a composite resin containing a filler in the resin, and the like as a material excellent in electrical insulation. You may form the main body of the wiring board 2 using. Alternatively, in order to improve the light reflectivity on the chip mounting surface 2a of the wiring board 2 and improve the light emission efficiency of the semiconductor light emitting device 1, silicone containing white pigment such as alumina powder, silica powder, magnesium oxide, titanium oxide or the like is used. It is preferable to use a resin. On the other hand, in order to obtain better heat dissipation, the main body of the wiring board 2 may be made of metal. In this case, it is necessary to electrically insulate the wiring pattern of the wiring board 2 from the metal body.

  As shown in FIG. 1, a plate-like transparent substrate 4 made of glass is disposed so as to face the chip mounting surface 2a of the wiring substrate 2 on which the LED chip 3 is mounted. For convenience, the wiring board 2 and the transparent substrate 4 are shown separated from each other in FIG. 1, but as will be described later, the wiring board 2 and the transparent substrate 4 are actually arranged close to each other. The material of the transparent substrate 4 is not limited to glass, and the transparent substrate 4 may be formed using a resin having translucency with respect to the light emitted from the LED chip 3.

  As shown in FIGS. 1 and 2, the wavelength conversion unit 5 that converts at least a part of the wavelengths of the light emitted from the LED chip 3 includes a first wavelength conversion region P1 (first wavelength conversion member) and a second wavelength conversion unit. The wavelength conversion region P2 (second wavelength conversion member) is divided into two wavelength conversion regions. Corresponding to the division of the wavelength conversion unit 5, each LED chip 3 mounted on the wiring board 2 also has a first wavelength conversion region P1 and a second wavelength conversion region as shown in FIGS. 1 and 2. It is divided into two LED groups corresponding to each position of P2. That is, as shown in FIG. 2, when the semiconductor light emitting device 1 is viewed in plan (that is, in the XY plan view of the semiconductor light emitting device 1), the first wavelength conversion region P1 and the second wavelength conversion region P2 Ten LED chips 3 are arranged for each of the two wavelength conversion regions. Here, “corresponding” means that the first wavelength conversion region P1 is provided so as to face (that is, overlap or overlap) the first LED group D1, and the second wavelength conversion region P2 faces the second LED group D2. The state that was provided. In the following description, when the LED chip 3 is referred to separately for each wavelength conversion region, a or b is added to the end of the code corresponding to the first wavelength conversion region P1 and the second wavelength conversion region P2. Shall. From the above, the ten LED chips 3a located at the position corresponding to the first wavelength conversion region P1 constitute the first LED group D1, and the ten LED chips 3b located at the position corresponding to the second wavelength conversion region P2. Constitutes the second LED group D2.

  Therefore, in the present embodiment, the first light emitting unit U1 and the second light emitting unit U1 and the second wavelength converting region P2 are combined with the first LED group D1 and the second LED group D2 corresponding to the first wavelength converting region P1 and the second wavelength converting region P2, respectively. A two-light-emitting unit U2 is configured. That is, the first LED group D1 and the first wavelength conversion region P1 constitute the first light emitting unit U1, and the second LED group D2 and the second wavelength conversion region P2 constitute the second light emitting unit U2. In the present embodiment, the first light emitting unit U1 and the second light emitting unit U2 are integrally provided and constitute the semiconductor light emitting device 1 that is a light emitting unit group. In the following, the light emitted from each of the first light emitting unit U1 and the second light emitting unit U2 is referred to as primary light, and the primary light emitted from each of the first light emitting unit U1 and the second light emitting unit U2 is synthesized. In addition, the light emitted from the semiconductor light emitting device 1 is referred to as synthesized light.

  3 is a cross-sectional view of the semiconductor light-emitting device 1 taken along the line III-III in FIG. 2, and FIG. 4 is an enlarged view of a main part on the first light-emitting unit U1 side of the cross-sectional view shown in FIG. FIG. 5 is an enlarged view of a main part on the first light emitting unit U2 side of the cross-sectional view shown in FIG. As shown in FIG. 3, the transparent substrate 4 is joined to the wiring substrate 2 via a plurality of spacers 6, and by interposing these spacers 6, as shown in FIGS. 4 and 5, A gap is provided between each LED chip 3.

  The gap provided here is provided with a distance L1 calculated in advance so that the light emitted from the LED chip 3 reaches the wavelength conversion unit 5 at a position corresponding to the LED chip 3 with certainty. If the LED chip 3 is made as close as possible to the wavelength conversion unit 5, the light emitted from the LED chip 3 will surely reach the wavelength conversion unit 5, but the LED chip 3 is close to the wavelength conversion unit 5. If it is too high, the wavelength conversion section 5 may be heated by the heat generated by the LED chip 3, and the wavelength conversion function and the light emission efficiency may be reduced. For this reason, in order to prevent such an excessive temperature rise, it is preferable that the space | interval of LED chip 3 and the wavelength conversion part 5 is 0.01 mm or more.

  If the semiconductor light emitting device 1 has a thermal margin, the first surface 4a of the transparent substrate 4 may be brought into close contact with the LED chip 3 without providing such a gap. Even when the LED chip 3 and the transparent substrate 4 are separated from each other, the gap may be sealed with a translucent silicone resin, epoxy resin, glass, or the like. By doing so, the light from the LED chip 3 can be efficiently guided to the wavelength converter 5.

  In the present embodiment, the wavelength converter 5 is provided on the second surface 4b of the transparent substrate 4. However, the wavelength converter 5 is provided on the first surface 4a of the transparent substrate 5, that is, the surface on the wiring substrate 2 side. You may make it provide. In this case as well, it is possible to provide an appropriate gap between the wavelength conversion unit 5 and the LED chip 3 as in the present embodiment, but when there is a thermal margin, the wavelength conversion unit 5 Can be brought into close contact with or close to the LED chip 3.

(LED chip)
In the present embodiment, an LED chip that emits blue light having a peak wavelength of 460 nm is used as the LED chip 3. Specifically, as such an LED chip, for example, there is a GaN-based LED chip in which an InGaN semiconductor is used for a light emitting layer. Note that the type and emission wavelength characteristics of the LED chip 3 are not limited thereto, and various semiconductor light emitting elements such as LED chips can be used without departing from the gist of the present invention. In the present embodiment, the peak wavelength of light emitted from the LED chip 3 is preferably in the wavelength range of 360 nm to 480 nm, and more preferably in the wavelength range of 440 nm to 470 nm.

  As shown in FIGS. 4 and 5, a p-electrode 7 and an n-electrode 8 are provided on the surface of the LED chips 3a and 3b facing the wiring board 2 side. In the case of the LED chip 3 shown in FIG. 4, the p electrode 7 is bonded to the wiring pattern 9 formed on the chip mounting surface 2a of the wiring substrate 2, and the wiring pattern 10 also formed on the chip mounting surface 2a is connected to the n. The electrode 8 is joined. The p electrode 7 and the n electrode 8 are connected to the wiring pattern 9 and the wiring pattern 10 by soldering via metal bumps (not shown). Other LED chips 3 (not shown) are also bonded to the wiring pattern formed on the chip mounting surface 2a of the wiring board 2 corresponding to each LED chip 3 in the same manner. Has been.

  The method of mounting the LED chip 3 on the wiring board 2 is not limited to this, and an appropriate method can be selected according to the type and structure of the LED chip 3. For example, after the LED chip 3 is bonded and fixed to a predetermined position of the wiring board 2, two electrodes of each LED chip 3 may be connected to a corresponding wiring pattern by wire bonding, or one electrode may be connected as described above. While joining to a corresponding wiring pattern, you may make it connect the other electrode to a corresponding wiring pattern by wire bonding.

(Wavelength converter)
As described above, the wavelength conversion unit 5 is divided into two first wavelength conversion regions P1 and second wavelength conversion regions P2 corresponding to the first LED group D1 and the second LED group D2. As shown in FIGS. 3 and 4, the first wavelength conversion region P <b> 1 among the two wavelength conversion regions constituting the wavelength conversion unit 5 is further configured by two layers. Specifically, the first wavelength conversion region P <b> 1 includes a light diffusion layer 11 formed on the transparent substrate 4 and an organic phosphor layer 12 formed on the light diffusion layer 11. The light diffusing layer 11 includes light diffusing particles 11 a that diffuse light emitted from the LED chip 3 and a filler 11 b that disperses and holds the light diffusing particles. The light diffusing layer 11 emits light emitted from the LED chip 3. It has the effect of diffusing and spreading the light over the entire surface of the wavelength conversion region P1. Further, the organic phosphor layer 12 includes a red organic phosphor 12a that converts the wavelength of blue light emitted from the LED chip 3 to emit red light, and a filler 12b that disperses and holds the red organic phosphor. Has been. The film thickness of the wavelength conversion region 12 is preferably 10 μm or more. The reason will be described in the evaluation results described later.

  On the other hand, as shown in FIG. 5, the second wavelength conversion region P2 is composed of one layer. Specifically, the second wavelength conversion region P2 includes a green inorganic phosphor 13a that converts the wavelength of blue light emitted from the LED chip 3 and emits green light, and a filler that holds the inorganic phosphor dispersedly. 13b. The second wavelength conversion region P2 may include a yellow inorganic phosphor that emits yellow light by converting the wavelength of the blue light emitted from the LED chip 3, instead of the green inorganic phosphor 13a. The yellow inorganic phosphor may be further included in addition to 13a.

  The organic phosphor is not limited to the red organic phosphor, and may be an organic phosphor of another color that converts light from the LED chip into light of another color. Similarly, the inorganic phosphor is not limited to the green inorganic phosphor and the yellow inorganic phosphor, and may be an inorganic phosphor of another color that converts light from the LED chip into light of another color. .

  In the following, light diffusing particles 11a and filler 11b constituting the light diffusing layer 11, red organic phosphor 12a and filler 12b constituting the organic phosphor layer 12, and green which is an inorganic phosphor forming the wavelength conversion region P2. Specific examples of the inorganic phosphor 13a and the filler 13b and the above-described yellow phosphor will be described.

(Light diffusion particles)
In the present embodiment, as the light diffusing particles 11a, a light diffusing material such as an inorganic light diffusing material made of an inorganic compound or an organic light diffusing material made of an organic compound can be used.

  Inorganic light diffusing materials include silicon oxide (silica), white carbon, talc, magnesium oxide, zinc oxide, titanium oxide, aluminum oxide, zirconium oxide, boron oxide, calcium carbonate, aluminum hydroxide, barium sulfate, calcium silicate, silicic acid Materials such as magnesium, aluminum silicate, sodium aluminosilicate, zinc silicate, glass, mica and the like can be mentioned.

  Examples of the organic light diffusing material include materials such as styrene (co) polymers, acrylic (co) polymers, siloxane (co) polymers, and polyamide (co) polymers. Here, “(co) polymer” means both “polymer” and “copolymer”.

  Of the above-described materials, zinc oxide, titanium oxide, aluminum oxide, silicon oxide, zirconium oxide, calcium carbonate, and boron oxide, which are small amounts and have a large light diffusion effect, are preferable.

  The average particle diameter of the light diffusion particles 11a is usually 10 μm or less, preferably 0.1 to 10 μm, more preferably 0.1 to 5 μm, and further preferably 1 to 5 μm. If the particle size of the light diffusion particle 11a is too large, the leakage light of the excitation light increases. On the other hand, if the particle size of the light diffusing particles 11a is too small, the effect of shielding excitation light is reduced. Here, the average particle diameter of the light diffusing particles 11a is a 50% average particle diameter based on volume, and is a value of a median diameter (D50) of a volume reference particle size distribution measured by a laser or diffraction scattering method.

  One kind of the inorganic light diffusing material and the organic diffusing material used as the light diffusing particles 11a described above may be used alone, or two or more kinds having different materials and average particle diameters may be used in combination.

  The content of the light diffusing material (light diffusing particles 11a) in the first wavelength conversion region P1 is preferably 1.0% by weight or more and 70% by weight or more. The reason will be described in the evaluation results described later.

(Red organic phosphor)
Examples of the red phosphor 12a include β-diketonates, β-diketones, aromatic carboxylic acids, red organic phosphors composed of rare earth element ion complexes having an anion such as Bronsted acid as a ligand, and perylene pigments (for example, Dibenzo {[f, f ′]-4,4 ′, 7,7′-tetraphenyl} diindeno [1,2,3-cd: 1 ′, 2 ′, 3′-lm] perylene), porphyrin pigment , Anthraquinone pigment, lake pigment, azo pigment, quinacridone pigment, anthracene pigment, isoindoline pigment, isoindolinone pigment, phthalocyanine pigment, triphenylmethane basic dye, indanthrone pigment, Indophenol pigments, cyanine pigments, dioxazine pigments and the like can be mentioned. Of these, perylene pigments and porphyrin pigments are particularly preferred. The red organic phosphor is not limited to these. One of the above materials may be used alone, or two or more may be used in combination.

  The concentration of the red phosphor (organic phosphor) in the first wavelength conversion region P1 is preferably 10% by weight or less, and more preferably 0.1% by weight or more and 5.0% by weight or less. The reason will be described in the evaluation results described later.

(Green inorganic phosphor)
The emission peak wavelength of the green phosphor 13a is usually 500 nm or more, preferably 510 nm or more, more preferably 515 nm or more, and usually less than 550 nm, preferably 542 nm or less, more preferably 535 nm or less. It is. Among them, as the green phosphor, for example, Y ₃ (Al, Ga) ₅ O ₁₂ : Ce, CaSc ₂ O ₄ : Ce, Ca ₃ (Sc, Mg) ₂ Si ₃ O ₁₂ : Ce, (Sr, Ba) ₂ SiO ₄ : Eu, (Si, Al) ₆ (O, N) ₈ : Eu (β-sialon), (Ba, Sr) ₃ Si ₆ O ₁₂ : N ₂ : Eu, SrGa ₂ S ₄ : Eu, BaMgAl ₁₀ O ₁₇ : Eu and Mn are preferable.

(Yellow inorganic phosphor)
The emission peak wavelength of the yellow phosphor is usually 530 nm or more, preferably 540 nm or more, more preferably 550 nm or more, and usually 620 nm or less, preferably 600 nm or less, more preferably 580 nm or less. is there. Among them, as the yellow phosphor, for example, Y ₃ Al ₅ O ₁₂ : Ce, (Y, Gd) ₃ Al ₅ O ₁₂ : Ce, (Sr, Ca, Ba, Mg) ₂ SiO ₄ : Eu, (Ca, Sr) Si ₂ N ₂ O ₂ : Eu, α-sialon, La ₃ Si ₆ N ₁₁ : Ce (however, a part thereof may be substituted with Ca or O) are preferable.

(Filler)
A thermoplastic resin, a thermosetting resin, a photocurable resin, or the like is used for the filler 11b that disperses and holds the light diffusing particles 11a. However, the filler 11b is sufficiently transparent to the blue light emitted from the LED chip 3. It is preferable to use a material having high durability. Specifically, for example, (meth) acrylic resins such as methyl poly (meth) acrylate, styrene resins such as polystyrene and styrene-acrylonitrile copolymer, polycarbonate resins, polyester resins, phenoxy resins, butyral resins, polyvinyl alcohol, Examples thereof include cellulose resins such as ethyl cellulose, cellulose acetate, and cellulose acetate butyrate, epoxy resins, phenol resins, and silicone resins. Also, inorganic materials such as metal alkoxides, ceramic precursor polymers or solutions containing metal alkoxides by hydrolytic polymerization by a sol-gel method or a combination of these, solidified inorganic materials such as siloxane bonds. The inorganic material and glass which it has can be used.

  As the filler 12b for dispersing and holding the red phosphor 12a, at least one of a thermoplastic polymer resin, a thermosetting polymer resin, a reactive polymer resin, and an ultraviolet curable resin can be used. Two or more kinds of resins may be selected from these resins and used in combination.

  Examples of the thermoplastic polymer resin include PVC, vinyl acetate resin, polyvinyl alcohol resin, vinyl acetal resin, vinyl carbazole resin, vinylidene chloride resin, polyethylene resin, polypropylene resin, styrene resin, methacrylic resin, polyamide resin, polycarbonate resin, A simple substance or a copolymer such as an acetal resin, an ether chloride resin, a fluororesin, or a polyurethane resin can be used.

  Examples of the thermosetting polymer resin and the reactive polymer resin include a simple substance or a copolymer such as a phenol resin, a urea resin, a melamine resin, an unsaturated polyester resin, an epoxy resin, a silicone resin, and a reactive polyurethane resin. Can be used.

  As the ultraviolet curable resin, for example, epoxy acrylate, polyester acrylate, polyether acrylate, urethane acrylate, or the like can be used.

  For the filler 13b for dispersing and holding the inorganic phosphor such as the green inorganic phosphor 13a and the yellow inorganic phosphor, a thermoplastic resin, a thermosetting resin, a photocurable resin, or the like is used. It is preferable to use a material having sufficient transparency and durability against the emitted blue light. Specifically, for example, (meth) acrylic resins such as methyl poly (meth) acrylate, styrene resins such as polystyrene and styrene-acrylonitrile copolymer, polycarbonate resins, polyester resins, phenoxy resins, butyral resins, polyvinyl alcohol, Examples thereof include cellulose resins such as ethyl cellulose, cellulose acetate, and cellulose acetate butyrate, epoxy resins, phenol resins, and silicone resins. Also, inorganic materials such as metal alkoxides, ceramic precursor polymers or solutions containing metal alkoxides by hydrolytic polymerization by a sol-gel method or a combination of these, solidified inorganic materials such as siloxane bonds. The inorganic material and glass which it has can be used.

(Average transmittance in the first wavelength conversion region)
In the first wavelength conversion region P1 according to the embodiment, the average transmittance that is the probability of transmitting the primary light emitted from the LED chip 3a is 20% or less, preferably 5% or less, more preferably 3% or less, and further Preferably it is 2% or less, particularly preferably 1% or less and 0.01% or more. When the average transmittance is 20% or more, the wavelength conversion efficiency (that is, the emissivity of red light) in the first wavelength conversion region P1 is low, and good synthesized light is emitted from the semiconductor light emitting device 1. Can not be.

Here, the transmittance refers to the first wavelength conversion region when the first wavelength conversion region P1 is provided in the predetermined region with respect to the amount of light passing through the predetermined region when the first wavelength conversion region P1 is not provided. It is the ratio of the amount of light transmitted through P1. That is, transmittance f (λ) at wavelength λ = (transmitted light intensity at wavelength λ) / (incident light intensity at wavelength λ).

  The average transmittance of the first wavelength conversion region P1 in the present embodiment can be calculated using, for example, a measurement result using a microspectrophotometer (MCPD2000, Otsuka Electronics Co., Ltd.) and the following mathematical formula (1). .

  Blue light emitted from the LED chip 3a constituting the first LED group D1 reaches the organic phosphor layer 12 while being diffused by the light diffusion layer 11 due to the configuration of the wavelength conversion unit 5 as described above. And the organic fluorescent substance layer 12 converts the wavelength of a part of blue light which reached | attained, and radiates | emits red light. Further, the blue light that has not been wavelength-converted by the organic phosphor layer 12 is emitted as it is from the organic phosphor layer 12 (that is, passes through the organic phosphor layer 12). On the other hand, the blue light emitted from the LED chip 3b constituting the second LED group D2 reaches the second wavelength conversion region P2. And in the 2nd wavelength conversion area | region P2, the wavelength of a part of blue light which reached | attained is converted, and green light is radiated | emitted. Further, the blue light that has not been wavelength-converted in the second wavelength conversion region P2 is radiated as it is from the second wavelength conversion region P2 (that is, passes through the second wavelength conversion region P2). When the second wavelength conversion region P2 includes a yellow inorganic phosphor, yellow light is also emitted from the second wavelength conversion region P2.

  As described above, blue light, red light, green light, or yellow light is emitted from the wavelength conversion unit 5, and for an observer who views the semiconductor light emitting device 1 of the present embodiment, the semiconductor light emitting device. The combined light of blue light, red light, and green light or yellow light is emitted from 1. Further, when a green inorganic phosphor and a yellow inorganic phosphor are used as the inorganic phosphor, blue light, red light, green light, and yellow light are radiated from the wavelength conversion unit 5, and this embodiment For an observer who views the semiconductor light emitting device 1 of the embodiment, the combined light of blue light, red light, green light, and yellow light is emitted from the semiconductor light emitting device 1. For example, by emitting blue light, red light, and green light in a balanced manner, the combined light becomes white light.

(Lighting device using semiconductor light emitting device)
FIG. 6 is an electric circuit diagram showing an outline of the electric circuit configuration of the illumination device 20 using the semiconductor light emitting device 1 described above. As shown in FIG. 6, in the semiconductor light emitting device 1, in addition to the LED chip 3a of the first LED group D1 and the LED chip 3b of the second LED group D2, the current limiting resistor R1 and resistor R2, and each LED group are provided. Are provided with a transistor Q1 and a transistor Q2 for supplying a driving current for each LED chip 3. The resistors R1 and R2 are provided to limit the current flowing through the corresponding LED chip 3 to an appropriate magnitude (for example, 60 mA per LED chip 3).

  Specifically, ten LED chips 3a constituting the first LED group D1 are connected in parallel with the same polarity, and the anode of each LED chip 3a is connected to the positive electrode of the power source 21 via the resistor R1. Has been. The cathode of each LED chip 3 a is connected to the collector of the transistor Q 1, and the emitter of the transistor Q 1 is connected to the negative electrode of the power source 21. The ten LED chips 3b constituting the second LED group D2 are also connected in parallel with the same polarity. Like the LED chip 3a, the anode is connected to the positive electrode of the power supply 21 via the resistor R2. The cathode is connected to the negative electrode of the power source 21 via the transistor Q2.

  In such an electric circuit configuration, when the transistor Q1 is turned on, a forward current supplied from the power source 21 flows to each LED chip 3a of the first LED group D1, and each LED chip 3a emits light. Therefore, by turning on the transistor Q1, blue light and red light are emitted from the first light emitting unit U1 including the first LED group D1 and the first wavelength conversion region P1 corresponding to the first LED group D1.

  Similarly, when the transistor Q2 is turned on, a forward current supplied from the power source 21 flows to each LED chip 3b of the second LED group D2, and the LED chip 3b emits light. Therefore, by turning on the transistor Q2, blue light and green light are emitted from the second LED group D2 and the second light emitting unit U2 including the second wavelength conversion region P2 corresponding to the second LED group D2.

  When the amount of power supplied to the second LED group D2 is larger than the amount of power supplied to the first LED group D1 due to the configuration of the semiconductor light emitting device 1 as described above, the amount of light emitted from the second light emitting unit U2. Therefore, the combined light emitted from the semiconductor light emitting device 1 is greatly affected by the emitted light emitted from the second light emitting unit U2. Therefore, as the amount of power supplied to the second LED group D2 becomes larger than the amount of power supplied to the first LED group D1, the combined light emitted from the semiconductor light emitting device 1 changes from white to cyan (only the first wavelength conversion group P1). To the primary light color). On the other hand, when the amount of power supplied to the second LED group D2 is smaller than the amount of power supplied to the first LED group D1, the amount of light emitted from the first light emitting unit U1 increases, and the semiconductor light emitting device 1 emits light. The effect of the radiated light radiated | emitted from the 1st light emission unit U1 becomes large for the synthesized light to be performed. Therefore, as the amount of power supplied to the first LED group D1 becomes larger than the amount of power supplied to the second LED group D2, the combined light emitted from the semiconductor light emitting device 1 changes from white to magenta (only the second wavelength conversion group P2). To the primary light color). That is, the color temperature of the synthesized light can be changed by the control.

As described above, by changing the amount of power supplied to the first LED group D1 and the second LED group D2, it is possible to adjust the combined light emitted from the semiconductor light emitting device 1 to light of various colors. That is, the color temperature of the synthesized light can be changed by the control.
In the present embodiment, as a method of specifically changing the amount of electric power, the transistor corresponding to each light emitting unit is intermittently turned on and off at a predetermined cycle, and the duty ratio of the current supply pulse at this time is adjusted. Thus, a method of adjusting the power supplied to the LED group of the light emitting unit is used.

  In order to control such on / off states of the transistors Q1 and Q2, the light emitting control unit 22 is provided in the illumination device 20 of the present embodiment. Both the transistors Q1 and Q2 can be switched on / off according to the respective base signals, and the base signals are individually sent from the light emission control unit 22 to the respective bases.

  As described above, by controlling the on / off states of the transistors Q1 and Q2, the color temperature of the combined light of the semiconductor light emitting device 1 can be changed. Therefore, the color temperature of the combined light is adjusted from the outside. The lighting device 20 of the present embodiment is provided with an operation unit 23. The operation unit 23 is connected to the light emission control unit 22 and transmits an electrical signal corresponding to the set color temperature to the light emission control unit 22 in response to an external operation for setting the color temperature of the combined light. An instruction corresponding to the set color temperature is given.

(First modification)
In the embodiment described above, the wavelength conversion unit 5 is divided into one first wavelength conversion region P1 and one second wavelength conversion region P2, and the first wavelength conversion region P1 and the second wavelength conversion region P2 are juxtaposed. It was. However, instead of such a pattern of the wavelength conversion unit 5, a pattern as shown in FIG. 7 may be used, and the wavelength conversion unit 5 ′ formed in such a pattern will be described below as a first modification. To do. FIG. 7 is a plan view of the semiconductor light emitting device 1 according to this embodiment, and is a different pattern diagram of the wavelength conversion unit.

  As shown in FIG. 7, in the wavelength conversion unit 5 ′ of the present modification, the wavelength conversion unit 5 ′ is divided into two first wavelength conversion regions P1 ′ and two second wavelength conversion regions P2 ′, and the first wavelength conversion region P1. 'And the second wavelength conversion region P2' are alternately arranged. That is, the wavelength conversion unit 5 ′ has a structure in which first wavelength conversion regions P1 ′ and second wavelength conversion regions P2 ′ formed in a stripe shape are alternately arranged. The structure of the first wavelength conversion region P1 ′ is the same as the first wavelength conversion region P1 of the first embodiment described above, and the structure of the second wavelength conversion region P2 ′ is the same as the second wavelength conversion region P2 described above. Therefore, the description of the layer structure and materials is omitted.

  In such a case, the plurality of LED chips 3 are also divided into a first ELD group D1 ′ corresponding to the first wavelength conversion region P1 ′ and a second ELD group D2 ′ corresponding to the second wavelength conversion region P2 ′. The first ELD group D1 ′ and the second ELD group D2 ′ are alternately arranged.

  In this way, by forming the pattern of the wavelength conversion unit 5 ′, each wavelength conversion region is adjacent to other wavelength conversion regions, so that the primary light emitted from the wavelength conversion unit 5 ′ can be combined well. It becomes possible.

(Second modification)
In the embodiment described above, the wavelength conversion unit 5 is divided into one first wavelength conversion region P1 and one second wavelength conversion region P2, and the first wavelength conversion region P1 and the second wavelength conversion region P2 are juxtaposed. It was. However, instead of such a pattern of the wavelength conversion unit 5, a pattern as shown in FIG. 8 may be used, and the wavelength conversion unit 5 ″ formed in such a pattern will be described below as a second modification. 8 is a plan view of the semiconductor light emitting device 1 according to the present embodiment, and is a pattern diagram with different wavelength conversion units.

  As shown in FIG. 8, in the wavelength conversion unit 5 ″ of this modification, the wavelength conversion unit 5 ″ is divided into a plurality of cell regions corresponding to each LED chip 3, and the first wavelength conversion region P1 ″. And the second wavelength conversion region P2 ″ are arranged in a lattice pattern. The structure of the first wavelength conversion region P1 ″ is the same as the first wavelength conversion region P1 of the first embodiment described above, and the structure of the second wavelength conversion region P2 ″ is the same as the second wavelength conversion region P2 described above. Therefore, the description of the layer structure and materials is omitted.

  In such a case, the LED chips 3a and the LED chips 3b are latticed so as to correspond to the first wavelength conversion regions P1 ″ and the LED chips 3a, respectively. Will be arranged.

  In this way, by forming the pattern of the wavelength conversion unit 5 ″, each wavelength conversion region is adjacent to a plurality of other wavelength conversion regions, so that the primary light emitted from the wavelength conversion unit 5 ″ can be combined better. It becomes possible to do.

(Third Modification)
In the embodiment described above, the transparent substrate 4 and the wavelength conversion unit 5 are arranged in parallel to the wiring substrate 2. However, instead of such a shape of the transparent substrate 4 and the wavelength conversion unit 5, the shape as shown in FIG. 9 may be used, and the light emitting device 31 including the transparent substrate and the wavelength conversion unit formed in this way is the third one. A modification will be described below. FIG. 9 is a cross-sectional view showing the semiconductor light emitting device 31 according to this modification in the same cross section as FIG. Further, the parts different from the first embodiment are only the transparent substrate and the wavelength conversion unit, and the same components as those in the first embodiment are denoted by the same reference numerals and the description thereof is omitted.

  As shown in FIG. 9, the transparent substrate 34 has a bent shape at the center. For example, the angle of bending at the central portion is an obtuse angle. The transparent substrate 34 is bonded to the wiring substrate 2 via the spacer 6 at both ends. Therefore, the transparent substrate 34 is not parallel to the wiring substrate 2 but is inclined with respect to the wiring substrate 2. Specifically, the transparent substrate 34 is inclined with respect to the wiring substrate 2 so that the distance between the wiring substrate 2 and the transparent substrate 34 increases toward the center of the wiring substrate 2. That is, the transparent substrate 34 has a bent shape so that its XY cross section is substantially V-shaped.

  The wavelength conversion unit 35 is formed on the transparent substrate 34. Specifically, the first wavelength conversion region P31 is disposed on the −X side from the central portion of the transparent substrate 34, and the second wavelength conversion region P32 is disposed on the + X side from the central portion of the transparent substrate 34. Therefore, the first wavelength conversion region P31 and the second wavelength conversion region P32 are not parallel to the wiring board 2 but are arranged to be inclined. That is, the wavelength conversion unit 35 also has a bent shape so that its XY cross section is substantially V-shaped. The structure of the first wavelength conversion region P31 is the same as the first wavelength conversion region P1 of the first embodiment described above, and the structure of the second wavelength conversion region P32 is the same as the second wavelength conversion region P2 described above. Therefore, description of the layer structure and materials is omitted.

(Fourth modification)
In the embodiment described above, the transparent substrate 4 and the wavelength conversion unit 5 are arranged in parallel to the wiring substrate 2. However, in place of such a shape of the transparent substrate 4 and the wavelength conversion unit 5, the shape as shown in FIG. 10 may be used, and the light emitting device 41 including the transparent substrate and the wavelength conversion unit formed in this way is the fourth. A modification will be described below. FIG. 10 is a cross-sectional view showing the semiconductor light emitting device 41 according to this modification in the same cross section as FIG. Further, the parts different from the first embodiment are only the transparent substrate and the wavelength conversion unit, and the same components as those in the first embodiment are denoted by the same reference numerals and the description thereof is omitted.

  As shown in FIG. 10, the transparent substrate 44 is curved and is bonded to the wiring substrate 2 via the spacers 6 at both ends. Specifically, the transparent substrate 44 is curved so that the central portion is the farthest from the wiring substrate 2. Therefore, the distance between the transparent substrate 44 and the wiring substrate 2 increases toward the central portion. That is, the transparent substrate 44 is formed in a substantially bowl shape, and has a curved shape so that its XY cross section becomes a substantially U shape.

  Further, as shown in FIG. 8, an entirely curved wavelength conversion unit 45 is formed on the transparent substrate 44. Specifically, the first wavelength conversion region P41 is disposed on the −X side from the central portion of the transparent substrate 44, and the second wavelength conversion region P42 is disposed on the + X side from the central portion of the transparent substrate 44. Accordingly, the first wavelength conversion region P41 and the second wavelength conversion region P42 are not parallel to the wiring board 2, but are substantially inclined. That is, the wavelength converter 35 also has a curved shape so that its XY cross section is substantially U-shaped. The structure of the first wavelength conversion region P41 is the same as the first wavelength conversion region P1 of the first embodiment described above, and the structure of the second wavelength conversion region P42 is the same as the second wavelength conversion region P2 described above. Therefore, description of the layer structure and materials is omitted.

  If the transparent substrate and the wavelength conversion unit can be shaped as in the third and fourth modifications as described above, the emission surface side of the semiconductor light emitting device (in accordance with the environment in which the semiconductor light emitting device is used) That is, it is possible to optimize the shape of the surface side on which the wavelength conversion unit is provided. Moreover, when used for a lighting fixture, the designability of the lighting fixture can be improved.

(Effects of this embodiment)

  In the semiconductor light emitting device 1 of the present embodiment, the wavelength conversion unit 5 includes a first wavelength conversion region P1 including the red organic phosphor 12a and the light diffusion particles 11a, and a second wavelength conversion region P2 including the green inorganic phosphor 13a. Since it is comprised, the light radiated | emitted from LED chip 3 is wavelength-converted into the light according to each fluorescent substance in each wavelength conversion area | region.

  Further, in the semiconductor light emitting device 1 of the present embodiment, since the average transmittance of the first wavelength conversion region P1 is 20% or less, the light from the LED chip is favorably wavelength-converted to other light according to the organic phosphor. Can be converted.

  Therefore, with such a configuration of the semiconductor light emitting device 1, desired synthesized light can be supplied and cost reduction can be easily achieved.

  In addition, by forming the lighting device 20 using the semiconductor light emitting device 1 described above, it is possible to supply light with various color temperatures and to manufacture the lighting device 20 at low cost.

  In the above-described embodiment, the light emitting unit is formed by associating the wavelength conversion region with the LED group, but the present invention is not limited to such a form. For example, in the case where combined light (for example, white light) having the same color temperature is always emitted from the semiconductor light emitting device, the LED group is not configured, and the arrangement of the LED chips is irrelevant to the pattern shape of the wavelength conversion region. Desired white light may always be emitted.

Second Embodiment
In the first embodiment, the first wavelength conversion region P1 constituting the wavelength conversion unit 5 has a two-layer structure including the light diffusion layer 11 and the organic phosphor layer 12, but the first wavelength conversion region is It may be composed of one layer. A semiconductor light-emitting device having such a wavelength conversion member will be described in detail as a second embodiment with reference to FIGS. 11 and 12. In addition, since it is the same as that of 1st Embodiment about structures other than a 1st wavelength conversion area | region, about the members and structures other than a 1st wavelength conversion area | region, the same code | symbol as 1st Embodiment is attached | subjected, The Description is omitted.

(Configuration of semiconductor light emitting device)
FIG. 11 is an enlarged cross-sectional view showing the main part on the first wavelength conversion region P51 side of the semiconductor light emitting device 51 according to the present embodiment in the same manner as FIG. FIG. 12 is a schematic configuration diagram of the first wavelength conversion region P51 of the semiconductor light emitting device 51 according to this embodiment. As shown in FIG. 11, the first wavelength conversion region P51 is formed on the transparent substrate 4 and has a single-layer structure. Although not shown, the second wavelength conversion region has the same structure as that of the first embodiment and has a one-layer structure.

  As shown in FIG. 12, the first wavelength conversion region P51 has a light diffusion particle 52 that diffuses light emitted from the LED chip 3, and a red light that emits red light by converting the wavelength of blue light emitted from the LED chip 3a. The organic phosphor 53 is composed of a filler 54 for dispersing and holding the light diffusion particles 52 and the red organic phosphor 53. Therefore, in the first wavelength conversion region P51, there are the light diffusion particles 52 that are radiated from the LED chip 3 and diffuse blue light, and the red organic phosphor 53 that converts blue light into red light. That is, the first wavelength conversion region 51 in the present embodiment does not have a two-layer structure of a light diffusion layer including light diffusion particles and an organic phosphor layer including red organic phosphors, and the light diffusion particles are included in one layer. 52 and a red organic phosphor 53 are mixed.

  The light diffusing particles 52 are the same as the light diffusing particles 11a of the first embodiment, the red organic phosphor 53 is the same as the red organic phosphor 12a of the first embodiment, and the filler 54 is Since it is the same as the filler 12b of 1st Embodiment mentioned above, description of the layer structure, material, etc. is abbreviate | omitted.

  Even when the first wavelength conversion region P51 according to the present embodiment is used in the semiconductor light emitting device 51, the same effect as the semiconductor light emitting device 1 according to the first embodiment can be obtained. That is, the semiconductor light emitting device 51 can supply desired synthesized light and can easily reduce the cost.

  In addition, since the light diffusing particles 52 and the red phosphor particles 53 are mixed and close to each other, the blue light diffused by the light diffusing particles 52 is favorably converted into red light by the red phosphor particles 53. be able to. That is, the wavelength conversion efficiency in the first wavelength conversion region 51 can be improved, and the amount of red light emitted from the first wavelength conversion region 51 can be increased.

<Third Embodiment>
In the first embodiment described above, the semiconductor light emitting device 1 is configured by the plurality of LED chips 3 mounted on the wiring substrate 2 and the wavelength conversion unit 5 provided on the light transmitting substrate 4. However, the semiconductor light emitting layer of the present invention is not limited to such a form, and can be variously changed or replaced without departing from the gist of the present invention. Accordingly, an example of a semiconductor light emitting device having a structure different from the structure of the first embodiment will be described below as a third embodiment of the present invention.

(Configuration of semiconductor light emitting device)
FIG. 13 is a perspective view showing a basic configuration of the semiconductor light emitting device 101 according to the present embodiment, and FIG. 14 is a plan view of the semiconductor light emitting device 101. The semiconductor light emitting device 101 includes LED chips 103 that are mounted in four rows on a chip mounting surface 102a of a wiring board 102 made of an alumina-based ceramic having excellent electrical insulation and good heat dissipation. Further, on the chip mounting surface 102 a of the wiring substrate 102, an annular and truncated cone-shaped reflector (wall member) 104 is provided so as to surround the LED chips 103.

  The inner side of the reflector 104 is divided into a first area 106 and a second area 107 by a partition member 105. In the first area 106, one of the LED chips 103 arranged in two rows is arranged, and in the second area 107, the other LED chip 103 is arranged. Yes. The reflector 104 and the partition member 105 can be formed of resin, metal, ceramic, or the like, and are fixed to the wiring board 102 using an adhesive or the like. Moreover, when using the material which has electroconductivity for the reflector 104 and the partition member 105, the process for giving electrical insulation with respect to the wiring pattern mentioned later is needed. Hereinafter, for convenience of explanation, the LED chip 103 arranged in the first region 106 is also referred to as an LED chip 103a, and the LED chip 103 arranged in the second region 107 is also referred to as an LED chip 103b.

  Note that the number of LED chips 103 in the present embodiment is an example, and can be increased or decreased as necessary. One LED chip 103 can be provided for each of the first region 106 and the second region 107, respectively. It is also possible to vary the number in the area. Also, the material of the wiring board 102 is not limited to alumina ceramics, and various materials can be applied, for example, ceramic, resin, glass epoxy, composite resin containing filler in the resin, etc. A selected material may be used. Furthermore, in order to improve the light reflectivity on the chip mounting surface 102a of the wiring substrate 102 and improve the light emission efficiency of the semiconductor light emitting device 101, silicone containing white pigment such as alumina powder, silica powder, magnesium oxide, titanium oxide or the like is used. It is preferable to use a resin. On the other hand, it is also possible to improve heat dissipation using a metal substrate such as a copper substrate or an aluminum substrate. However, in this case, it is necessary to form a wiring pattern on the wiring board with electrical insulation therebetween.

  Further, the shapes of the reflector 104 and the partition member 105 described above are examples, and can be variously changed as necessary. For example, instead of the reflector 104 and the partition member 105 formed in advance, a dispenser or the like is used to form an annular wall portion (wall member) corresponding to the reflector 104 on the chip mounting surface 102a of the wiring board 102, and then the partition member 105. A partition wall (partition member) corresponding to may be formed. In this case, examples of the material used for the annular wall portion and the partition wall portion include a paste-like thermosetting resin material or a UV curable resin material, and a silicone resin containing an inorganic filler is preferable.

  As shown in FIGS. 13 and 14, in the first region 106 in the reflector 104, four LED chips 103 are arranged in a row in parallel with the extending direction of the partition member 105, and the second region in the reflector 104. 107 also includes four LED chips 103 arranged in a row in parallel with the extending direction of the partition member 105. In FIG. 14, the reflector 104 and the partition member 105 are indicated by broken lines for convenience.

  On the chip mounting surface 102a of the wiring substrate 102, wiring patterns 108, 109, 110 and 111 for supplying a driving current to each of the LED chips 103 are formed as shown in FIG. In the wiring pattern 108, a connection terminal 108a for external connection is formed at one end portion outside the reflector 104, and the other end portion side in the first region 106 is partitioned as shown in FIG. It extends in parallel with the member 105. Further, the wiring pattern 109 has a connection terminal 109a for external connection formed at one end portion outside the reflector 104, and the other end portion side in the first region 106 is as shown in FIG. The partition member 105 extends in parallel.

  The four LED chips 103 in the first region 106 are connected in parallel between the wiring pattern 108 and the wiring pattern 109 formed in this manner with the same polarity direction. More specifically, the LED chip 103 has two electrodes (not shown) for supplying driving current on the surface of the wiring board 102 side. These LED chips 103 have one electrode (p electrode) connected to the wiring pattern 108 and the other electrode (n electrode) connected to the wiring pattern 109.

  On the other hand, in the wiring pattern 110, a connection terminal 110a for external connection is formed at one end portion outside the reflector 104, and the other end portion side in the second region 107 is as shown in FIG. The partition member 105 extends in parallel. Further, the wiring pattern 111 has a connection terminal 111a for external connection formed at one end portion outside the reflector 104, and the other end portion side in the second region 107 is as shown in FIG. The partition member 105 extends in parallel.

  The four LED chips 103 in the second region 107 are connected in parallel between the wiring pattern 110 and the wiring pattern 111 thus formed with the same polarity direction. More specifically, these LED chips 103 have one electrode (p electrode) connected to the wiring pattern 110 and the other electrode (n electrode) connected to the wiring pattern 111.

  The mounting of the LED chip 103 and the connection of both electrodes to each wiring pattern employ flip chip mounting and are performed via eutectic solder via metal bumps (not shown). The method for mounting the LED chip 103 on the wiring substrate 102 is not limited to this, and an appropriate method can be selected according to the type and structure of the LED chip 103. For example, double wire bonding in which the LED chip 103 is bonded and fixed to a predetermined position of the wiring substrate 102 as described above and then the electrodes of the LED chip 103 are connected to the corresponding wiring pattern by wire bonding may be employed. This electrode may be bonded to the wiring pattern as described above, and single wire bonding may be employed in which the other electrode is connected to the wiring pattern by wire bonding.

  In the first region 106 and the second region 107 in the reflector 104, wavelength conversion members having different wavelength conversion characteristics are accommodated so as to cover the LED chip 103. A specific wavelength conversion member will be described below with reference to FIG.

  15 is a cross-sectional view of the semiconductor light emitting device 101 taken along line XV-XV in FIG. As shown in FIG. 15, in the semiconductor light emitting device 101, the first wavelength conversion member 121 is accommodated in the first region 106 in the reflector 104 so as to cover the four LED chips 103 a. In the second region 107, the second wavelength conversion member 122 is accommodated so as to cover the four LED chips 103b.

  The first wavelength conversion member 121 includes a light diffusion particle 131 that diffuses light emitted from the LED chip 103a, a red organic phosphor 132 that emits red light by converting the wavelength of blue light emitted from the LED chip 103a, and diffusion. It is comprised from the 1st translucent material 133 which disperse | distributes and hold | maintains particle | grains 113 and red organic fluorescent substance 132. FIG. Meanwhile, the second wavelength conversion member 122 disperses and holds the green inorganic phosphor 134 that converts the wavelength of the blue light emitted from the LED chip 103 b and emits green light, and the green inorganic phosphor 134. It is comprised from the property material 135. The second wavelength conversion member 122 may include a yellow inorganic phosphor that converts yellow light emitted from the LED chip 103b and emits yellow light instead of the green inorganic phosphor 134. The green inorganic phosphor In addition to 134, the yellow inorganic phosphor may further be included.

  Therefore, in this embodiment, the wavelength conversion unit 123 is configured by the wavelength conversion member 121 accommodated in the first region 106 and the wavelength conversion member 122 accommodated in the second region 107. That is, the wavelength conversion unit 123 is divided into a first wavelength conversion region formed in the first region 106 and a first wavelength conversion region formed in the second region 107.

(LED chip)
In the present embodiment, an LED chip that emits blue light having a peak wavelength of 460 nm is used as the LED chip 3. Specifically, as such an LED chip, for example, there is a GaN-based LED chip in which an InGaN semiconductor is used for a light emitting layer. Note that the type and emission wavelength characteristics of the LED chip 3 are not limited thereto, and various semiconductor light emitting elements such as LED chips can be used without departing from the gist of the present invention. In the present embodiment, the peak wavelength of light emitted from the LED chip 3 is preferably in the wavelength range of 360 nm to 480 nm, and more preferably in the wavelength range of 440 nm to 470 nm.

(Wavelength conversion member)
The diffusion particles 113, the red organic phosphor 132, the green inorganic phosphor 134, and the yellow inorganic phosphor are the same as the diffusion particles 11a, the red organic phosphor 12a, the green inorganic phosphor 13a, and the yellow inorganic phosphor of the first embodiment. Consists of the same material. On the other hand, as the 1st translucent material 133, the material provided with translucency, such as an epoxy resin, a silicone resin, an acrylic resin, can be used, for example. Moreover, as the 2nd translucent material 135, the material provided with translucency, such as an epoxy resin, a silicone resin, an acrylic resin, can be used, for example.

  The semiconductor light emitting device 101 according to the present embodiment can be applied to a lighting device in the same manner as the semiconductor light emitting device 1 according to the first embodiment. Here, the semiconductor light emitting device 101 of the present embodiment has the same electric circuit configuration as the semiconductor light emitting device 1 of the first embodiment, and the semiconductor light emitting device 1 of the first embodiment is changed to the semiconductor light emitting device 101 of the present embodiment. If replaced, the lighting device functionally identical to the lighting device 20 of the first embodiment can be configured. Therefore, since the electrical circuit configuration of the illumination device of the semiconductor light emitting device 101 is the same as the electrical circuit configuration of the illumination device 20 of the first embodiment, the description thereof is omitted.

  Even when the first wavelength conversion member 121 according to the present embodiment is used in the semiconductor light emitting device 101, the same effects as those of the semiconductor light emitting device 1 according to the first embodiment can be obtained. That is, the semiconductor light emitting device 101 can supply desired synthesized light and can easily reduce the cost.

  Further, since the light diffusing particles 131 and the red phosphor particles 132 are mixed and exist in the vicinity, the blue light diffused by the light diffusing particles 131 is favorably converted into red light by the red phosphor particles 132. be able to. That is, the wavelength conversion efficiency in the first wavelength conversion member 121 can be improved, and the amount of red light emitted from the first wavelength conversion member 121 can be increased.

<Evaluation of the first wavelength conversion member>
First, the concentration of the red organic phosphor in the first wavelength conversion member (first wavelength conversion region) in the third embodiment described above is changed, and the peak wavelength (nm) of red light and the fluorescence intensity with respect to the concentration of the red organic phosphor. Was measured.

  Specifically, 1 g of binder resin (MRX-HF manufactured by Teikoku Inc.) and red fluorescent dye “Lumogen F Red 305” manufactured by BASF (0.0085 g, 0.017 g, 0.02125 g, 0.0255 g, 0.0425 g) 0.085 g) and 0.1 g of “CR-1” manufactured by Baukousky Japan Co., Ltd. were placed in the same container and mixed and stirred by Nawataro Awatori (Sinky Co., Ltd.). 6 types of wavelength conversion members (Examples 1 to 6) by applying onto a PET resin having a thickness of 100 μm using ST-310F1G) and solidifying the resin by drying it by heating at 80 ° C. for 30 minutes. ) Was produced.

  Specifically, light of 360 to 480 nm is incident on Examples 1 to 6, and the peak wavelength of red light emitted from Examples 1 to 6 is measured using a Hitachi fluorescence spectrophotometer “F4500”. did. Further, the fluorescence intensity of the red light emitted from Examples 1 to 6 was measured using a luminance meter “SpecBos1200” manufactured by JETI. The evaluation results are shown in Table 1 below.

  As can be seen from Table 1, in order to emit good red light from the first wavelength conversion member, the concentration of the red phosphor is preferably 10 wt% or less. More preferably, the concentration of the red phosphor is adjusted to 0.1 wt% or more and 5.0 wt% or less. Particularly preferably, the concentration of the red phosphor is adjusted to about 4% by weight.

  Next, by changing the film thickness of the first wavelength conversion member (first wavelength conversion region) and the amount of the light diffusing material included in the third embodiment described above, the average transmittance (%) and the peak of the blue emission spectrum are changed. The intensity and the peak intensity of the red emission spectrum were measured.

  Specifically, 1 g of binder resin (MRX-HF manufactured by Teikoku Ink Co., Ltd.) and 0.017 g of red fluorescent dye “Lumogen F Red 305” manufactured by BASF Co. are placed in the same container, and mixed by Awatori Nertaro (Sinky Co., Ltd.). By applying the agitated material on a PET resin having a thickness of 100 μm using a screen printing machine (ST-310F1G manufactured by Okuhara Electric Co., Ltd.) and drying it by heating at 80 ° C. for 30 minutes to solidify the resin. Wavelength conversion members (Examples 7 to 10) were produced.

  In addition, 1 g of binder resin (MRX-HF manufactured by Teikoku Ink Co., Ltd.), 0.017 g of red fluorescent dye “Lumogen F Red 305” manufactured by BASF, “CR-1” manufactured by Baukosky Japan Co., Ltd. (0.1 g: Example 11) , 0.5 g: Examples 12 to 16) were put in the same container and mixed and stirred by Nawataro Awatori (manufactured by Shinky Corporation), and the thickness was measured using a screen printing machine (ST-310F1G manufactured by Okuhara Electric Co., Ltd.). A wavelength conversion member (Examples 11 to 16) was produced by applying the resin onto a 100 μm PET resin and drying it by heating at 80 ° C. for 30 minutes to solidify the resin. In addition, adjustment of the film thickness of the wavelength conversion member was performed by repeatedly coating the wavelength conversion member using a screen printer.

  As a specific measurement, light of 360 to 480 nm is incident on Examples 7 to 16, and the peak intensity of the blue emission spectrum and the peak intensity of the red emission spectrum emitted from Examples 7 to 16 are measured by Ocean Optics. The measurement was performed using a fiber multichannel spectrometer “USB2000”. The evaluation results are shown in Table 1 below and FIG. FIG. 16 is a graph showing the relationship between the wavelength of light emitted from each example and the peak intensity.

  As can be seen from Table 2, the wavelength conversion member (Examples 7 to 10) not including the light diffusing material did not increase the peak intensity of the red emission spectrum even when the film thickness of the wavelength conversion member was changed. Therefore, in order to radiate red light satisfactorily by converting the wavelength of blue light, it is necessary to mix a light diffusing material in the wavelength conversion member containing the red phosphor. Here, from the above results, it is preferable that the content of the light diffusing material in the first wavelength conversion member is 1.0 wt% or more and 70 wt% or less. In addition, since the quantity of the light-diffusion material in Table 2 is described in the ratio with respect to resin, it differs from the content rate of the light-diffusion material in a 1st wavelength conversion member.

  Further, from the results of Examples 12 to 15, it was found that when the film thickness of the wavelength conversion member was increased, the peak intensity of the red emission spectrum was increased. However, from the results of Example 16, it was also found that the peak intensity of the red emission spectrum does not increase when a certain film thickness is exceeded. From such results, the film thickness of the first wavelength conversion member is preferably 10 μm or more.

  Furthermore, from the results described above, it is possible to obtain a favorable peak intensity of the red emission spectrum by setting the average transmittance of the wavelength conversion member to 20% or less. Further, if the average transmittance is reduced, the peak intensity of the blue emission spectrum is reduced. Therefore, if the average transmittance is too small, blue light from the LED chip may be absorbed unnecessarily. However, in the present invention, since the blue light can be emitted also from the second wavelength conversion member (second wavelength conversion region), the blue light is not insufficient as the semiconductor light emitting device. Therefore, when the above-described semiconductor light emitting device is configured, the average transmission of the first wavelength conversion member is usually 0.01% or more.

<Evaluation of semiconductor light emitting device>
A semiconductor light emitting device having a wavelength conversion unit according to the second embodiment was manufactured as Example 17, and an emission spectrum and emission characteristics were evaluated. Hereinafter, a specific method for manufacturing a semiconductor light emitting device and evaluation results will be described.

  First, a blue LED chip having an emission peak wavelength of 460 nm was bonded to a terminal of a 3528 SMD type PPA (polyphthalamide) resin package with a transparent die bond paste. Thereafter, the die bond paste was cured by heating at 150 ° C. for 2 hours, and then the blue LED chip and the package electrode were wire-bonded with a gold wire having a diameter of 25 μm.

  Next, the two-part silicone resin was vacuum defoamed and mixed with a vacuum degassing apparatus “V-mini300” manufactured by EME, and 4 μL of this was injected into the recess of the SMD type resin package in which the blue LED was installed using a dispenser. did. Thereafter, the resin was cured by heating in an environment of 100 ° C. for 1 hour and further in an environment of 150 ° C. for 5 hours to obtain a light emitting part of the semiconductor light emitting device.

  Next, 1 g of binder resin (MRX-HF manufactured by Teikoku Ink Co., Ltd.), 0.017 g of red fluorescent dye “Lumogen F Red 305” manufactured by BASF, and light diffusion material “CR-1” manufactured by Baukousky Japan Co., Ltd. (aluminum oxide) ) 0.5 g was put in the same container and mixed and stirred by Nawataro Awatori (Sinky Corp.) and applied onto a PET resin with a thickness of 100 μm using a screen printing machine (ST-310F1G manufactured by Okuhara Denki Co., Ltd.). Then, it was dried by heating at 80 ° C. for 30 minutes to solidify the resin, thereby obtaining a first phosphor coating film (first wavelength conversion region, first wavelength conversion portion) having a film thickness of 13 μm. In addition, the said 1st fluorescent substance coating film is corresponded to the said Example 1, and the average transmittance | permeability is 13.2%.

Next, 1 g of binder resin (MRX-HF manufactured by Teikoku Ink Co., Ltd.) and YAG phosphor (Y ₃ (Al, Ga) ₅ O ₁₂ : Ce, CaSc ₂ O ₄ : Ce, Ca ₃ (Sc, Mg) ₂ Si ₃ 1 g of O ₁₂ : Ce) was put in the same container and mixed and stirred by Awatori Nertaro (Shinky Corp.) on a PET resin having a thickness of 100 μm using a screen printer (ST-310F1G manufactured by Okuhara Electric Co., Ltd.). The second phosphor coating film having a film thickness of 104 μm (second wavelength conversion region, second wavelength conversion section) was repeated six times by applying the resin to the resin and drying it by heating at 80 ° C. for 30 minutes to solidify the resin. Got.

  Next, each of the first phosphor coating film and the second phosphor coating film is cut into 17 mm × 28 mm, and the outer frame 36 mm × 28 mm (diameter 2 mm of the inner diameter of the opening) so as to be adjacent to each other in the horizontal direction. Adhered to the assay sheet. Two bonded phosphor coating films were placed on the upper surface of the light-emitting part obtained through the above-described steps to obtain a semiconductor light-emitting device (Example 17) that emits white light.

  Then, a current of 20 mA was passed through the obtained semiconductor light emitting device, and an emission spectrum was measured using a fiber multichannel spectroscope USB2000 (manufactured by Ocean Optics). The obtained emission spectrum is shown in FIG. In addition, Table 3 shows values of light emission characteristics of the obtained semiconductor light emitting device.

  Furthermore, the luminous efficiency of the obtained semiconductor light emitting device was about 30.3 lm / W, and it was also found that the luminous efficiency was excellent.

1, 31, 41, 51, 101 Semiconductor light emitting device 2,102 Wiring substrate 3, 3a, 3b, 103a, 103b LED chip (semiconductor light emitting element)
5, 35, 45, 123 Wavelength converter 11a Light diffusing particles (light diffusing material)
12a Red organic phosphor (organic phosphor)
13a Green inorganic phosphor (inorganic phosphor)
P1 first wavelength conversion region (first wavelength conversion member)
P2 Second wavelength conversion region (first wavelength conversion member)
111 1st wavelength conversion member 112 2nd wavelength conversion member

Claims (16)

A wiring board;
A semiconductor light emitting device disposed on the mounting surface of the wiring board and having an emission peak wavelength of 360 nm to 480 nm;
A wavelength conversion unit extending so as to intersect with the emitted light emitted from the semiconductor light emitting element, and converting the wavelength of at least a part of the emitted light,
The wavelength conversion unit includes an organic phosphor and a light diffusing material, a first wavelength conversion region in which an average transmittance of emitted light emitted from the semiconductor light emitting element is 20% or less, and a second wavelength conversion including an inorganic phosphor. The semiconductor light-emitting device is divided into regions in the extending direction of the wavelength converter.   2. The semiconductor light emitting device according to claim 1, wherein the concentration of the organic phosphor in the first wavelength conversion region is 10 wt% or less.   3. The semiconductor light emitting device according to claim 2, wherein a concentration of the organic phosphor in the first wavelength conversion region is 0.1 wt% or more and 5.0 wt% or less.   The semiconductor light emitting device according to claim 1, wherein the wavelength conversion unit is formed on a surface of a transparent substrate.   4. The semiconductor light emitting device according to claim 1, wherein the wavelength conversion unit is formed by being mixed with a translucent material. 5.   The said 1st wavelength conversion area | region is comprised from the organic fluorescent substance layer which consists of the said organic fluorescent substance, and the light-diffusion layer which becomes the said light-diffusion material, The any one of Claim 1 thru | or 5 characterized by the above-mentioned. The semiconductor light-emitting device as described.   The first wavelength conversion region has a laminated structure in which the organic phosphor layer is laminated on the light diffusion layer, and the light diffusion layer is closer to the semiconductor light emitting element than the organic phosphor layer. The semiconductor light-emitting device according to claim 6.   The semiconductor light-emitting device according to claim 1, wherein the organic phosphor is a red organic phosphor.   9. The semiconductor light emitting device according to claim 8, wherein the red organic phosphor has a perylene structure or a porphyrin structure.   The semiconductor light-emitting device according to claim 1, wherein the inorganic phosphor includes at least one of a green inorganic phosphor and a yellow inorganic phosphor.   The semiconductor light-emitting device according to claim 1, wherein a wavelength of an emission peak of the semiconductor light-emitting element is 440 nm to 470 nm.   12. The semiconductor light emitting device according to claim 1, wherein a content of the light diffusing material in the first wavelength conversion region is 1.0 wt% or more and 70 wt% or less.   2. The light diffusing material is one or more selected from the group consisting of zinc oxide, titanium oxide, aluminum oxide, silicon oxide, zirconium oxide, calcium carbonate, and boron oxide. 12. The semiconductor light emitting device according to any one of 12 above.   14. The semiconductor light emitting device according to claim 1, wherein a film thickness of the first wavelength conversion region is 10 μm or more.   The emitted light that has passed through the wavelength converter without being wavelength-converted by the wavelength converter, the first converted light that has been wavelength-converted by the organic phosphor, and the second converted light that has been wavelength-converted by the inorganic phosphor The semiconductor light emitting device according to claim 1, wherein white light is generated.   A lighting apparatus comprising the semiconductor light emitting device according to claim 1.

Images