JP4863794B2 - Wavelength converting material, method for producing the same, and light emitting device using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a novel fluorophor exerting blue to red color emission by near-ultraviolet excitation. <P>SOLUTION: This fluorophor which emits light by irradiation of a near-ultraviolet ray is represented by general formula (1); A<SB>2-x</SB>B<SB>x</SB>O<SB>1+x</SB>N<SB>2-x</SB>:RE wherein A is at least one kind of element selected from the group consisting of Si, Ge, and C; B is at least one kind of element selected from the group consisting of A1, Ga, B, and In; RE is at least one kind of element selected from the group consisting of Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, and Mn; and x represents a number satisfying 0&le;x&lt;0.3. <P>COPYRIGHT: (C)2008,JPO&amp;INPIT

Description

  The present invention relates to a novel wavelength conversion material that emits light in a blue to red range by near-ultraviolet excitation.

SiAlON phosphors are phosphors fired mainly from silicon nitride or aluminum nitride, and are of various types with different ratios of silicon Si, aluminum Al, oxygen O and nitrogen N, which are the main elements constituting the crystal structure. It has been known. Of these, α-SiAlON phosphors and β-SiAlON phosphors have been reported to be applied to LEDs and the like as wavelength conversion materials. For example, Patent Document 1, as SiAlON phosphor used in white light emitting diode as a light source a blue light emitting diode, the general formula _{Li x M y Ln z Si 12-} (m + n) Al (m + n) O n N An α-SiAlON phosphor represented by _16-n (M is at least one of Ca, Mg, and Y. Ln is at least one lanthanide) has been proposed. The emission peak of this α-SiAlON phosphor has a wavelength of about 560 nm to 590 nm and the color is yellow. Further, Patent Document 2, beta-SiAlON as a phosphor, having a beta-type Si ₃ N ₄ crystal structure, one has the general formula _{M a Si b1 Al b2 O c1} N c2 (M chosen Mn, Ce, Eu, Or two or more types of green phosphors have been proposed. This β-SiAlON phosphor has a peak at an emission wavelength of 500 nm to 600 nm.

Further, Patent Document 3 describes fluorescence of oxynitride having the structure MSiON, sialon having the structure MSiAl ₂ O ₃ N ₂ , M ₁₃ Si ₁₈ Al ₁₂ O ₁₈ N ₃₆ , MSi ₅ Al ₂ ON ₉ , and M ₃ Si ₅ AlON _10. LEDs using the body (in which the cation M is partially replaced by Eu, Ce) are disclosed.
SiAlON is a phosphor with excellent heat resistance due to the robustness of the crystal lattice, but there are few reports of blue ones. A barium magnesium aluminate phosphor (hereinafter referred to as a BAM phosphor) widely used as a blue light-emitting phosphor can obtain a high-efficiency blue light emission, but has a problem in heat resistance.

On the other hand, SiAlON (hereinafter referred to as O-SiAlON) having a higher ratio of Si to Al or N than α-SiAlON phosphor and β-SiAlON phosphor is disclosed in Patent Document 4 and Patent Document 5, It is described that the ceramic structural material is a material excellent in heat resistance, particularly heat resistance at high temperatures. However, there has been no report of phosphors manufactured using the materials (base materials) disclosed in Patent Documents 4 and 5 so far.
JP 2005-36038 A JP 2005-255895 A JP 2003-206481 A US Pat. No. 5,316,988 US Pat. No. 5,851,943

  The present invention provides a SiAlON phosphor, particularly a phosphor having an O-SiAlON or Sinoite structure, capable of obtaining a high-efficiency blue light emission, and by using such a phosphor as a wavelength conversion material, An object is to provide a good light-emitting device.

The phosphor of the present invention that solves the above problems is represented by the general formula (1) and emits light by irradiation with near-ultraviolet light (light having a wavelength range of about 300 nm to 420 nm) (hereinafter referred to as O-SiAlON phosphor). ).
A _2-x B _x O _{1 + x} N _2-x : RE (1)
(Wherein A is one or more elements selected from Si, Ge and C, B is one or more elements selected from A1, Ga, B and In, RE is Ce, It represents one or more elements selected from Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu and Mn, where x is a numerical value satisfying 0 ≦ x <0.3 To express.)

  The phosphor production method of the present invention is a method for producing the O-SiAlON phosphor by mixing raw materials and firing in a predetermined temperature range under nitrogen pressure, wherein the general formula (1) A phosphor having a desired emission wavelength is produced by adjusting the amount (x) of element B added.

  The phosphor production method of the present invention is a method for producing the O-SiAlON phosphor by mixing raw materials and firing in a predetermined temperature range under nitrogen pressure, wherein the general formula (1) A phosphor having a desired emission wavelength is produced by adjusting the concentration of RE.

  The light-emitting device of the present invention includes at least a semiconductor light-emitting element, an electrode connected to the light-emitting element, light that is emitted from the light-emitting element, and light that has a wavelength different from that of the light that is emitted from the light-emitting element. It has 1 type of wavelength conversion material and the sealing material which seals the said light emitting element, The O-SiAlON fluorescent substance of this invention mentioned above is included as said wavelength conversion material, It is characterized by the above-mentioned.

  In the light emitting device of the present invention, for example, a light emitting element having an emission peak wavelength in the range of 300 to 420 nm is used. The sealing material is preferably composed of one or more resins selected from epoxy resins, silicone resins, polydimethylsiloxane derivatives having an epoxy group, oxetane resins, acrylic resins, and cycloolefin resins.

  According to the present invention, a phosphor excellent in luminous efficiency and heat resistance is provided. Further, according to the present invention, it is possible to provide a white LED having excellent color rendering properties as compared with a conventional BAM phosphor.

Hereinafter, the phosphor of the present invention and the production method thereof will be described.
The O-SiAlON phosphor of the present invention has a composition represented by the general formula (1).
A _2-x B _x O _{1 + x} N _2-x : RE (1)
(In the formula, x represents a numerical value satisfying 0 ≦ x <0.3. The same applies hereinafter.)
A is one or more elements selected from Si, Ge, and C, B is one or more elements selected from A1, Ga, B, and In, and RE is a rare earth element or Mn It is. Typically, A is Si and B is A1.

The O-SiAlON phosphor of the present invention is based on a Sinoite structure represented by Si ₂ ON ₂ (x = 0), and Al and O are substituted for part of Si and N constituting the crystal structure. It has a structure (or a mixed phase with β'-type SiAlON) and doped with rare earth elements or Mn as an activator (RE) to emit blue to red light when irradiated with near ultraviolet light in the wavelength range of about 300 nm to 420 nm. Show.

  The addition amount (x) of the B element should be less than 0.3, and even if it is 0, it emits light. As the additive amount (x) of element B approaches 0.3, the emission wavelength shifts to a shorter wavelength. Further, the emission spectrum becomes broader as the addition amount (x) of B element approaches 0. Therefore, the emission wavelength and the wavelength range can be changed by adjusting the addition amount of the B element.

As RE, rare earth elements selected from Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu and Mn can be used, and in particular, Ce, Sm, Eu, It is preferable that it is 1 type, or 2 or more types obtained from Tb and Mn.
These rare earth elements or Mn (hereinafter collectively referred to as rare earth elements or the like) substitute for part of Si or Al in the crystal structure, and cause the phosphor to emit light. The emission wavelength of the phosphor of the present invention can be changed depending on the type and concentration of RE. Specifically, the concentration of RE is preferably in the range of 0.01 to 2 mol%. In such a range, for example, when RE is Eu, the peak wavelength range is about 420 to 490 nm. By changing RE, the peak wavelength range can be changed from about 370 nm (Ce) to 685 nm (Sm).

  The O-SiAlON phosphor of the present invention can be obtained by mixing raw materials and firing in a predetermined temperature range under nitrogen pressure. Hereafter, the specific example of the manufacturing method of the fluorescent substance of this invention is demonstrated.

  Silicon nitride, silicon dioxide, and aluminum nitride are weighed at a ratio adjusted so that a single phase is obtained after firing and mixed uniformly. To this, an appropriate amount of an oxide such as a rare earth element as an activator, or a carbonate or hydroxide that becomes an oxide by heating is added and mixed sufficiently to be uniform. Further, a compound such as a halide having a flux effect may be added as a material. A homogeneous mixture of these materials is put into a boron nitride crucible and 1 to 1950-1950 ° C. in a pressurized nitrogen atmosphere of 0.5 to 0.92 MPa in a multipurpose high temperature furnace using resistance heating of graphite. By baking for 10 hours, the O-SiAlON phosphor of the present invention is obtained.

  The O-SiAlON phosphor of the present invention thus produced becomes a phosphor that emits light when irradiated with near-ultraviolet light of 300 nm to 420 nm. At this time, a phosphor having an arbitrary wavelength peak can be obtained by adjusting the amount of B element (A1, Ga, B, In) added and the type and concentration of the rare earth element as an activator. Although the O-SiAlON phosphor of the present invention is not limited, it is suitably used for a high color rendering light-emitting device, particularly a light-emitting device for illumination, due to its light emission characteristics.

  Next, the light emitting device of the present invention using the above phosphor will be described. The light emitting device of the present invention is the same as the known light emitting device except that the O-SiAlON phosphor is used as the phosphor, and the structure and type are not particularly limited. FIG. 1 shows a typical light emitting device to which the present invention is applied as a first embodiment. The light-emitting device is provided on the base 7 so as to surround the semiconductor light-emitting element 1, the semiconductor light-emitting element 1 mounted on the base 7, the extraction electrode 6, the lead wire 2 connecting the extraction electrode 6 and the light-emitting element 1, and the semiconductor light-emitting element 1. And the sealing portion 4 that fills the recess 8. The phosphor is used as a wavelength conversion material 3 that emits light having a wavelength different from that of light emitted from the light emitting element 1, and is mixed in the sealing portion 4.

  As the semiconductor light emitting device 1, one having an emission peak wavelength range of 300 to 420 nm is used. Examples of the semiconductor light emitting device 1 that emits light within the above emission peak wavelength range include, for example, a group III-nitrogen compound (InGaAlN) semiconductor, a zinc oxide compound (ZnMgO) semiconductor, and a zinc selenide compound (ZnMgSeSTe) semiconductor. Typical examples include silicon carbide compound (SiGeC) semiconductors, but other compound semiconductors may be used as long as they emit light from ultraviolet light to near ultraviolet light. In the present invention, the semiconductor light emitting element 1 includes those fixed on the submount.

  The base body 7, the semiconductor light emitting element 1 and the lead electrode 6 can take various forms. The semiconductor light emitting element 1 is fixed on the base body 7, and each lead electrode 6 for the anode / cathode and the semiconductor light emitting element 1 are provided. It is only necessary that the anode / cathode electrode is electrically connected to each other. Typically, as shown in FIG. 1, an extraction electrode 6 for both anode and cathode electrodes is wired on a substrate 7 made of an insulating material such as glass fiber or epoxy resin. The semiconductor light emitting element 1 is fixed on the substrate 7 with an adhesive such as an epoxy resin, and the anode / cathode electrodes of the semiconductor light emitting element 1 are electrically joined by the corresponding lead electrode 6 and the conductive wire 2. Alternatively, although not shown, the anode / cathode electrodes corresponding to the anode / cathode electrodes of the semiconductor light emitting device 1 are represented by eutectic materials such as Au-Sn, Au bumps, anisotropic conductive sheets, and Ag pastes. With such a conductive resin or the like, it is electrically bonded and fixed to the base 7, and only one electrode of the semiconductor light emitting element 1 is electrically bonded to the corresponding extraction electrode 6 with the above-described material. The lead electrode 6 fixed to the base body 7 and corresponding to the other electrode can take a form of electrical connection with a conductive wire. Further, the base 7 may be made of a conductive material such as metal in order to improve the heat dissipation of the semiconductor light emitting device 1 and may also serve as a single electrode 6.

  The substrate 7 is preferably provided with a recess 8 in which the semiconductor light emitting element 1 is fixed inside. The concave portion 8 can be formed by various methods such as a method of integrally molding with the base body 7 and a method of bonding to the base body 7 later, and any method may be used in the present invention. The surface of the recess 8 may be any material as long as the lead electrode 6 of each electrode of the anode / cathode is not electrically short-circuited. For example, the surface of the recess 8 may be coated, plated, or deposited on the inside of the recess 8. A high reflectivity material may be formed. The shape of the recess 8 is preferably a substantially truncated cone, but may be a substantially quadrangular pyramid. Although it is desirable that the side wall of the recess 8 is inclined, in the case of a light-emitting device in which a thin element is desired, such as a white LED for a backlight light source for a display unit of a mobile phone, the end face is almost vertical. It may be.

  The material of the sealing part 4 filling the recess 8 may be any material that is transparent up to a wavelength region shorter than the emission peak wavelength from the semiconductor light emitting element 1 and can be mixed with the wavelength conversion material 3. Specifically, thermosetting resin, photocurable resin, low melting point glass, and the like can be given. Particularly preferred are thermosetting resins such as epoxy resins, silicone resins, polydimethylsiloxane derivatives having an epoxy group, oxetane resins, acrylic resins and cycloolefin resins. These resins can be used alone or in combination of two or more.

  The wavelength conversion material 3 needs to contain at least the O-SiAlON phosphor of the present invention. Further, the phosphor of the present invention can be combined with one or more other phosphors to form a color tone that cannot be achieved by the phosphor of the present invention alone. As another phosphor, a wavelength conversion material that absorbs near-ultraviolet light generated by the light-emitting element 1 or light emitted from the phosphor of the present invention and converts the wavelength to a longer wavelength than the absorbed light can be used.

Other phosphors include A ₃ B ₅ O ₁₂ : M (A: Gd, Lu, Tb, B: Al, Ga, M: Ce ³⁺ , Tb ³⁺ , Eu ³⁺ , Cr ³⁺ , N ⁺ , Pr ³⁺ or Er ³⁺ ), rare earth and manganese-doped barium-aluminum-magnesium compound phosphors (BAM: Mn phosphor), Y ₂ O ₂ S: Eu ³⁺ , ZnS: Cu, A1, etc. Representative sulfide compound phosphors, (Sr, Ca) S: Eu ²⁺ , CaGa ₂ S ₄ : Eu ²⁺ and thiogallate phosphors doped with rare earth such as SrGa ₂ S ₄ : Eu ²⁺ , or Generally known as phosphors containing at least one composition of aluminates such as TbAlO ₃ : Ce ³⁺ and silicates such as (Ba, Ca, Mg, Sr) _x Si _y O _z : Eu ²⁺ The materials of the respective wavelength conversion materials that are used can be used alone or in combination of two or more. Further, if necessary, scattering materials such as barium sulfate, magnesium oxide, and silicon oxide may be mixed in each wavelength conversion material for assisting reflection of excitation light and wavelength-converted light.

  The wavelength conversion material 3 can be used by mixing an appropriate amount with the sealing portion 4 described above. The mixing amount in the case of mixing with the resin is not particularly limited, but is usually about 1 to 50% by weight of the entire material constituting the sealing portion. The wavelength converting material 3 may be used by being dispersed in the transparent substrate 7.

  When the mixture of the resin of the sealing portion 4 and the wavelength conversion material 3 is filled in the concave portion 8, the height of the filling is the same as the height of the horizontal plane formed on the opening surface or a state where it is recessed more than that. Is preferred. The filling material only needs to be in a concave state in the end, and even if a dent is formed when filling the material, the dent is formed after curing with a convex shape when filling the sealant in the sealing part 4. But the effect is the same.

Next, FIG. 2 shows a light emitting device having a structure different from that of FIG. 1 as a second embodiment of the present invention. This light emitting device is formed of a molded package having one or more housings 17 each having a recess 18, and the light emitting element 11 is mounted on the bottom of the recess 18 of the housing 17. Although not shown, the anode / cathode electrode of the light emitting element 11 is connected to an external power source through a lead formed integrally with the housing 17. The upper portion (opening) of the recess 18 is covered with a transparent member 14 such as a glass plate or a resin plate, whereby the light emitting element 11 is sealed in a space (sealing portion) in the recess 18. The sealing portion is maintained at a pressure lower than atmospheric pressure or filled with a gas such as an inert gas such as N ₂ or Ar. A phosphor layer 13 is formed on at least one surface of the transparent member 14. In the illustrated embodiment, a first phosphor layer 131 is formed on the outer surface of the transparent member 14 that is directly above the light emitting element 11 so as to have a larger area than the light emitting element 11. A second phosphor layer 132 is formed on the inner surface of the transparent member 14 corresponding to the periphery of the layer 131.

  By arranging the first and second phosphor layers on both surfaces of the transparent member 14 in this way, a part of the light emitted from the light emitting element 1 is wavelength-converted by the first phosphor layer 131 to the outside. The light that is emitted and reflected by the back surface of the first phosphor layer 131 is converted in wavelength by the second phosphor layer 132 formed on the inner surface, and is emitted to the outside.

  The materials constituting the first and second phosphor layers may be the same or different, and at least one of them contains the O-SiAlON phosphor of the present invention. The phosphor layer 13 can be formed by depositing a phosphor containing the O-SiAlON phosphor of the present invention by screen printing, spin coating or the like. The amount of the O—SiAlON phosphor contained in the phosphor layer 13 is not particularly limited, but the total phosphor amount relative to the resin is approximately 1 to 80% by weight, preferably 3 to 50% by weight from the viewpoint of workability and the like. It is. The thickness of the phosphor layer is preferably 500 μm or less, more preferably 10 to 150 μm, from the viewpoint of light extraction efficiency.

  The light-emitting device of the present invention is suitable as a light source for general illumination or a light source for strobe light, and can emit light with high color rendering properties.

  Hereinafter, examples of the O-SiAlON phosphor of the present invention will be described.

<Example 1>
The following raw material compounds were uniformly dry-mixed. This was put into a boron nitride crucible (manufactured by Denki Kagaku Kogyo) and placed in a multipurpose high temperature furnace (manufactured by Fuji Denpa Kogyo). After evacuating the furnace to 10 Pa, the furnace was filled with 0.92 MPa of nitrogen and maintained at 1800 ° C. for 6 hours for firing. At this time, the temperature raising rate was set to 1425 ° C./h, and the system was allowed to cool in the furnace during cooling. The body color of the obtained fired product was white. The fired product was crushed in an alumina mortar and then sieved. The amount of aluminum added to this fired product (x in formula (1)) is about 0.3. The amount of europium added is 0.2 mol%.
Si ₃ N ₄ (Ube Industries) 0.960 mo1
AlN (High purity chemical) 0.826 mo1
Eu ₂ 0 ₃ (Furuuchi Chemical) 0.021 mo1
Si0 ₂ (Furuuchi Chemical) 4.534 mo1

<Example 2>
The same raw material compound as in Example 1 was used, and the dry mixing was uniformly performed with different mixing ratios. This was put into a boron nitride crucible (manufactured by Denki Kagaku Kogyo) and placed in a multipurpose high temperature furnace (manufactured by Fuji Denpa Kogyo). The furnace was evacuated to 10 Pa, filled with 0.92 MPa of nitrogen, maintained at 800 ° C. for 1 hour, and then maintained at 1900 ° C. for 6 hours for firing. At this time, the temperature raising rate was set to 1425 ° C./h, and the system was allowed to cool in the furnace during cooling. The body color of the obtained fired product was gray. The fired product was crushed in an alumina mortar and then sieved. The amount of aluminum added to this fired product (x in formula (1)) is about 0.06.
Si ₃ N ₄ (Ube Industries) 0.451 mo1
AlN (High purity chemical) 0.088 mo1
Eu ₂ 0 ₃ (Furuuchi Chemical) 0.06 mo1
Si0 ₂ (Furuuchi Chemical) 1.354 mo1

<Example 3>
The following raw material compounds were uniformly dry-mixed. This was put into a boron nitride crucible (manufactured by Denki Kagaku Kogyo) and placed in a multipurpose high temperature furnace (manufactured by Fuji Denpa Kogyo). The furnace was evacuated to 10 Pa, filled with 0.92 MPa of nitrogen, and maintained at 1800 ° C. for 3 hours for firing. At this time, the temperature raising rate was set to 1425 ° C./h, and the system was allowed to cool in the furnace during cooling. The body color of the obtained fired product was yellow. The fired product was crushed in an alumina mortar and then sieved. This fired product was confirmed to be a Sinoite crystal by X-ray diffraction.
Si ₃ N ₄ (Ube Industries) 0.500 mo1
Eu ₂ 0 ₃ (Furuuchi Chemical) 0.008 mo1
Si0 ₂ (Furuuchi Chemical) 1.274 mo1

<Comparative Example 1>
In order to produce a β-SiAlON phosphor (composition = Si _0.40 Al _0.012 O _0.027 N _0.55 : Eu) (Eu: 0.3 mol%), the following raw material compounds were used and uniformly mixed in the same manner as in Example 1. did. This was put into a boron nitride crucible (manufactured by Denki Kagaku Kogyo) and placed in a multipurpose high temperature furnace (manufactured by Fuji Denpa Kogyo). The furnace was evacuated to 10 Pa, filled with 0.92 MPa of nitrogen, and maintained at 1800 ° C. for 3 hours for firing. At this time, the temperature raising rate was set to 1425 ° C./h, and during the cooling, it was allowed to cool in the furnace (primary firing). The obtained fired product was crushed in an alumina mortar, and fired again under the same conditions as the primary firing (secondary firing). The body color of the obtained fired product was yellow. The fired product was crushed in an alumina mortar and then sieved.
Si ₃ N ₄ (Ube Industries) 0.903 mo1
AlN (High purity chemical) 0.088 mo1
Eu ₂ 0 ₃ (Furuuchi Chemical) 0.009 mo1

  The fired products (phosphor samples) obtained in Examples 1 to 3 and Comparative Example 1 were each excited with light having a dominant wavelength of 405 nm, and the emission spectrum at that time was measured with a spectrofluorometer (Hitachi F4500). did. The emission spectra of Examples 1 and 2 and Comparative Example 1 are shown in FIG. 3, and the emission spectrum of Example 3 is shown in FIG.

  As can be seen from the emission spectrum of FIG. 3, the phosphors of Examples 1 and 2 had emission peaks of around 455 nm and 475 nm, respectively, and emitted light different from the β-SiAlON phosphor of Comparative Example 1. It was shown that the emission spectrum of the europium-activated Ca-α-SiAlON phosphor (described in JP-A-2001-214162) having an emission peak around 600 nm is also different.

  The excitation spectra of the phosphors of Examples 1 and 2 and Comparative Example 1 are shown in FIG. From this excitation spectrum, it can be seen that the phosphor of the present invention is excited in the near ultraviolet region (300 to 420 nm). At the same time, it can be seen that the phosphor is different from the existing β-SiAlON phosphor (Comparative Example 1).

  As can be seen from the results of Example 1 (x≈0.3 in formula (1)) and Example 2 (x≈0.06 in formula (1)) with different Al contents, the amount of aluminum added is different. -Fluorescence characteristics were expressed even with SiAlON phosphor. Further, as shown in FIG. 5, even the Sinoite phosphor not containing aluminum (Example 3) exhibited fluorescence characteristics by near-ultraviolet excitation. As can be seen from the comparison of the emission spectra of Examples 1 to 3, the emission spectrum showed broader characteristics as the amount of aluminum added was smaller. The emission peak wavelength became longer as the amount added was smaller. Thus, it was shown that the characteristics of the phosphor can be controlled by changing the amount of aluminum added.

  Furthermore, the X-ray diffraction pattern of the phosphor sample of Example 1 and Comparative Example 1 and the X-ray diffraction pattern of the Ca-α-SiAlON phosphor which is a known substance are shown in FIG. From these X-ray diffraction patterns, it was confirmed that the O-SiAlON phosphor of the present invention was a new phosphor having a crystal structure different from that of the conventional SiAlON phosphor.

<Examples 4 and 5>
Next, in O-SiA10N having the same composition as in Example 1, phosphors were produced by changing the concentrations of rare earth elements as activators.

  The following raw material compounds were uniformly dry-mixed. This was put into a boron nitride crucible (manufactured by Denki Kagaku Kogyo) and placed in a multipurpose high temperature furnace (manufactured by Fuji Denpa Kogyo). The furnace was evacuated to 10 Pa, filled with 0.92 MPa of nitrogen, maintained at 800 ° C. for 1 hour, and then maintained at 1900 ° C. for 6 hours for firing. At this time, the temperature raising rate was set to 1425 ° C./h, and the system was allowed to cool in the furnace during cooling. The body color of the obtained fired product was gray. The fired product was crushed in an alumina mortar and then sieved.

Raw material for the phosphor of Example 4
Si ₃ N ₄ (Ube Industries) 0.960 mol
AlN (High purity chemical) 0.826 mol
Eu ₂ 0 ₃ (Furuuchi Chemical) O.115 mol
Si0 ₂ (Furuuchi Chemical) 4.534 mol

Raw material for phosphor of Example 5
Si ₃ N ₄ (Ube Industries) 0.960 mo1
AlN (High purity chemical) 0.826 mo1
Eu ₂ 0 ₃ (Furuuchi Chemical) 0.005 mo1
Si0 ₂ (Furuuchi Chemical) 4.534 mo1

  The emission spectra of the phosphors of Examples 4 and 5 are shown in FIG. 7 together with the emission spectrum of the phosphor of Example 1. The phosphors of Examples 4 and 5 are O-SiA10N having the same composition as that of Example 1. The amount of europium as an activator was 1 mol%, whereas Example 1 was 0.2 mol%. 0.05mo1%. As can be seen from the results of FIG. 7, the emission wavelength of the O-SiAlON phosphor of the present invention can be arbitrarily changed by changing the activator concentration.

  Next, in O-SiA10N having the same composition as that in Example 2, phosphors of Examples 6 to 9 were manufactured by changing the kind of rare earth element as an activator.

<Example 6>
The following raw material compounds were uniformly dry-mixed. This was put into a boron nitride crucible (manufactured by Denki Kagaku Kogyo) and placed in a multipurpose high temperature furnace (manufactured by Fuji Denpa Kogyo). After evacuating the furnace to 10 Pa, the furnace was filled with 0.92 MPa of nitrogen and maintained at 1800 ° C. for 6 hours for firing. At this time, the temperature raising rate was set to 1425 ° C./h, and the system was allowed to cool in the furnace during cooling. The body color of the obtained fired product was white. The fired product was crushed in an alumina mortar and then sieved.
Si ₃ N ₄ (Ube Industries) 0.451 mo1
AlN (High purity chemical) O.088 mo1
Eu ₂ 0 ₃ (Furuuchi Chemical) 0.011 mo1
Si0 ₂ (Furuuchi Chemical) 1.354 mo1
MnCO ₃ (High purity chemical) O.076 mo1

<Example 7>
The following raw material compounds were uniformly dry-mixed. This was put into a boron nitride crucible (manufactured by Denki Kagaku Kogyo) and placed in a multipurpose high temperature furnace (manufactured by Fuji Denpa Kogyo). The furnace was evacuated to 10 Pa, filled with 0.92 MPa of nitrogen, and maintained at 1900 ° C. for 8 hours for firing. At this time, the temperature raising rate was set to 1425 ° C./h, and the system was allowed to cool in the furnace during cooling. The body color of the obtained fired product was gray. The fired product was crushed in an alumina mortar and then sieved.
Si ₃ N ₄ (Ube Industries) 0.451 mo1
CeO ₂ (High purity chemical) O.005 mo1
AlN (High purity chemical) O.088 mo1
Si0 ₂ (High purity chemical) 1.354 mo1

<Example 8>
The following raw material compounds were uniformly dry-mixed. This was put into a boron nitride crucible (manufactured by Denki Kagaku Kogyo) and placed in a multipurpose high temperature furnace (manufactured by Fuji Denpa Kogyo). After evacuating the furnace to 10 Pa, the furnace was filled with 0.92 MPa of nitrogen and maintained at 1800 ° C. for 6 hours for firing. At this time, the temperature raising rate was set to 1425 ° C./h, and the system was allowed to cool in the furnace during cooling. The body color of the obtained fired product was white. The fired product was crushed in an alumina mortar and then sieved.
Si ₃ N ₄ (Ube Industries) 0.451 mo1
Tb ₄ O ₇ (High purity chemical) O.006 mo1
AlN (High purity chemical) O.088 mo1
Si0 ₂ (High purity chemical) 1.354 mo1

<Example 9>
The following raw material compounds were uniformly dry-mixed. This was put into a boron nitride crucible (manufactured by Denki Kagaku Kogyo) and placed in a multipurpose high temperature furnace (manufactured by Fuji Denpa Kogyo). After evacuating the furnace to 10 Pa, the furnace was filled with 0.92 MPa of nitrogen and maintained at 1800 ° C. for 6 hours for firing. At this time, the temperature raising rate was set to 1425 ° C./h, and the system was allowed to cool in the furnace during cooling. The body color of the obtained fired product was reddish brown. The fired product was crushed in an alumina mortar and then sieved.
Si ₃ N ₄ (Ube Industries) 0.451 mo1
Sm ₂ O ₃ (High purity chemical) O.011 mo1
AlN (High purity chemical) O.088 mo1
Si0 ₂ (High purity chemical) 1.354 mo1

  The emission spectra of the phosphors of Examples 6 to 9 are shown in FIG. As can be seen from the results of FIG. 8, the O-SiAlON phosphor of the present invention can obtain various luminescence by changing the type of activator.

<Example 10>
A light emitting device as shown in FIG. 1 was prepared by the following procedure.
First, as the substrate 7, an Ag-plated lead electrode 6 was prepared by integrally molding with a recess 8 (an end surface angle of about 52 ° serving as a wall) with a nylon resin having a high reflectance. As the semiconductor light emitting device 1, an InGaN-based compound semiconductor (emission wavelength peak: 395 nm) formed on an n-type SiC substrate was prepared. The semiconductor light emitting device 1 was electrically bonded to the lead electrode 6 corresponding to the cathode electrode formed on the n-type substrate with Ag paste and fixed to the substrate 7. On the other hand, the anode electrode formed on the InGaN-based compound semiconductor and the corresponding lead electrode were secured by an Au wire. As the wavelength conversion material 3, a material obtained by appropriately mixing the O-SiAlON phosphor of Example 1 and an orthosilicate phosphor which is a yellow phosphor was used. This mixed phosphor mixed with 20 wt% of silicone resin was filled to the end of the opening of the recess 8 and cured at 150 ° C. for 2 hours to produce a light emitting device. The chromaticity coordinates at that time were (0.30, 0.34).

<Comparative example 2>
The O-SiAlON phosphor was changed to a conventional BAM phosphor (manufactured by Kasei Optonics), and a light-emitting device was fabricated in the same manner as in Example 10 using a wavelength conversion material prepared so that the chromaticity coordinates were the same. .

  The emission spectra and average color rendering coefficient (Ra) of the light emitting devices of Example 10 and Comparative Example 2 are shown in FIG. The average color rendering coefficients (Ra) of Example 10 and Comparative Example 2 are 80 and 73, respectively, and it was confirmed that white LED elements having excellent color rendering properties can be obtained by using the O-SiAlON phosphor of the present invention. It was.

  According to the present invention, a phosphor excellent in luminous efficiency as compared with a conventional BAM phosphor is provided. By using this phosphor, a white LED element excellent in color rendering can be produced. The phosphor of the present invention can be applied to all fields in which near-ultraviolet phosphors are used, such as general illumination light sources, strobe light sources, and the like.

The figure which shows one Embodiment of the light-emitting device with which this invention is applied. The figure which shows other embodiment of the light-emitting device to which this invention is applied. The figure which shows the emission spectrum of the fluorescent substance of Example 1, 2 and the comparative example 1 The figure which shows the excitation spectrum of the fluorescent substance of Example 1, 2 and the comparative example 1 The figure which shows the emission spectrum of the fluorescent substance of Example 3. The figure which shows the X-ray-diffraction data of the fluorescent substance of Example 1 and Comparative Example 1 The figure which shows the emission spectrum of the fluorescent substance of Example 1, 4, 5 The figure which shows the emission spectrum of the fluorescent substance of Examples 6-9 The figure which shows the emission spectrum of the light-emitting device of Example 10 and Comparative Example 2.

DESCRIPTION OF SYMBOLS 1 ... Light emitting element, 2 ... Conductive wire, 3 ... Wavelength conversion material, 4 ... Sealing part, 6 ... Extraction electrode, 7 ... Base | substrate, 8 ... Recessed part.

Claims (9)

A phosphor that is represented by the general formula (1) and emits light by near-ultraviolet irradiation.
A _2-x B _x O _{1 + x} N _2-x : RE (1)
(Wherein A is one or more elements selected from Si, Ge and C, B is one or more elements selected from A1, Ga, B and In, RE is Ce, Represents one or more elements selected from Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, and Mn, where x satisfies 0 ≦ x <0.3. (Represents a numerical value.)   2. The phosphor according to claim 1, wherein in the general formula (1), A is Si, B is Al, and the value of x is 0 <x <0.3.   The phosphor according to claim 1, wherein in the general formula (1), A is Si and the value of x is 0.   The phosphor according to any one of claims 1 to 3, wherein in the general formula (1), RE is one or more elements selected from Ce, Sm, Eu, Tb, and Mn.   A method for producing a phosphor according to any one of claims 1 to 4, wherein raw materials are mixed and fired in a predetermined temperature range under nitrogen pressure, wherein the element B of the general formula (1) A method for producing a phosphor, comprising producing a phosphor having a desired emission wavelength by adjusting the addition amount (x).   A method for producing a phosphor according to any one of claims 1 to 4, comprising mixing raw materials and firing in a predetermined temperature range under nitrogen pressure, wherein the concentration of RE in the general formula (1) A method for producing a phosphor, characterized in that a phosphor having a desired emission wavelength is produced by adjusting the above. A semiconductor light emitting element, an electrode connected to the light emitting element, at least one wavelength conversion material that absorbs light emitted from the light emitting element and emits light having a wavelength different from that of light emitted from the light emitting element; In a light emitting device having a sealing material for sealing the light emitting element,
A light emitting device comprising the phosphor according to claim 1 as the wavelength conversion material. The light-emitting device according to claim 7,
The light emitting device has a light emission peak wavelength in a range of 300 to 420 nm. The light-emitting device according to claim 7 or 8,
The said sealing material consists of 1 type, or 2 or more types of resin chosen from an epoxy resin, a silicone resin, the polydimethylsiloxane derivative which has an epoxy group, an oxetane resin, an acrylic resin, and a cycloolefin resin, The light-emitting device characterized by the above-mentioned .

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