JP2010155891A - Nitride red phosphor and white light emitting diode utilizing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a novel nitride red phosphor capable of easily controlling a composition of a phosphor amount and improving homogeneity and reproducibility and a method for producing the same, a white light emitting diode having high color rendering properties and high luminous efficiency, and a white LED package utilizing the same. <P>SOLUTION: The nitride red phosphor represented by formula 1 below is provided. Formula 1: Ba<SB>2-x</SB>Re<SB>x</SB>Al<SB>y</SB>Si<SB>5-y</SB>N<SB>8</SB>(wherein a molar ratio has a value satisfying the following: 0.0001≤x≤1.0 and 0.001≤y≤5.0. Re is at least one or more elements selected from rare earth elements or transition metal elements). Having high color rendering properties and luminous efficiency, the white LED is available for lighting applications requiring high color rendering properties and greatly contributes activation of related industries, such as related techniques, that is, an LED production technique and a phosphor production technique, etc. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a nitride red phosphor and a white light emitting diode using the same. More specifically, a novel nitride red phosphor capable of easily controlling the composition of the amount of phosphor and improving uniformity and reproducibility, a method for producing the same, and the nitride red phosphor as a light source The present invention relates to a new white light emitting diode having high color rendering properties and high light emission efficiency, and a white light emitting diode package using the same.

  Efforts to apply light emitting diodes (hereinafter abbreviated as LEDs) to lighting began in the late 1990s. In 2006, the global market for lighting phosphors reached approximately $ 2 billion, the LED lighting market is expected to grow by more than 20% annually, and the global market size in 2012 will exceed $ 10 billion. Growth is expected. LEDs have higher reliability than existing lighting fixtures, have a long lifetime, have a low maintenance cost, and have a low power consumption, contributing greatly to energy saving. In addition, since the fluidity and heat generation of the design are low, it has various usage conditions as lighting.

  With the technical achievements of the first GaN-based LED, green and blue LEDs, the three primary colors of light, red, green and blue, can all be obtained from the LED. Subsequently, white LEDs that use YAG phosphors for blue LEDs are produced through continuous technological development, and technical developments that use red, green, and blue phosphors for ultraviolet LEDs are ongoing.

  Currently, white LEDs are used for display backlight light sources for mobile phones, flash light sources for mobile phones equipped with cameras, backlight light sources for LCD monitors, and the like. Furthermore, technological development for new luminaires to replace conventional incandescent lamps and fluorescent lamps is also in progress due to the rapid rise in energy prices.

  White LEDs are several times more efficient than incandescent lamps in terms of efficiency, and are almost the same level as fluorescent lamps. Their lifetime is 10 times longer than fluorescent lamps and 20 times longer than incandescent lamps. The fixture is attracting attention as a reliable next-generation lighting fixture because it has an energy saving effect of 80% or more compared to existing lighting fixtures. Although it is still expensive at present, it takes some time for general dissemination. However, the application of the technology of the present invention in the era of high energy prices like the present one can expect enormous energy savings. As a result, it is expected that the spread to the new lighting market will be expanded sooner or later.

  Currently, as a method of manufacturing an illuminating lamp using a semiconductor light source, there is a white LED using a YAG-based orange phosphor as a blue LED.

  In addition, there is a white LED in which a color rendering index (CRI) is improved by combining a near-ultraviolet or violet LED with a red, green, blue phosphor, or yellow-red phosphor.

  In addition, there are white LEDs that use red and green LEDs in combination.

  However, white LEDs that use YAG phosphors as blue LEDs have low color rendering properties, and are limited in terms of light efficiency limitations and temperature effects due to Stokes transition, so improvement is required. ing.

  A white LED that uses a YAG phosphor for a blue LED has low color rendering because it uses two wavelengths of blue and yellow.

  FIG. 1 is a distribution diagram of a wavelength spectrum of a white LED according to the prior art.

  That is, FIG. 1 shows the wavelength spectrum of a white LED manufactured as a blue LED and a YAG phosphor.

  Referring to FIG. 1, since there is a region where the emission intensity (Intensity) suddenly decreases in the wavelength region between blue and green, it can be confirmed that the color rendering index (Ra) is low. it can.

  FIG. 2 is a CIE chart of a white LED according to the prior art.

  In FIG. 2, B-LED indicates a blue LED, and Y-phosphor indicates yellow in which a part of blue is converted in wavelength by a YAG phosphor. The white light moved along the connection line between the B-LED and the Y-phosphor, and expressed as W.

  Referring to FIG. 2, since it has two wavelengths of blue and yellow, the red component is insufficient, so the color rendering property is as low as about 60 to 75 and is not suitable for use in general indoor lighting.

  As described above, the method of obtaining white light using a YAG phosphor widely known as a method for producing a white LED has a low color rendering property due to the low efficiency of the phosphor and a small amount of red component. There are many difficulties in the fabrication technique such as uniformity and reproducibility of the mixing ratio of epoxy and phosphor.

  A white LED using three red, green, and blue LEDs exhibits the highest luminous efficiency because there is no light loss. However, in order to realize an accurate white color, it is necessary to accurately control the drive driver. Also, since the product is large and the temperature characteristics of the three LEDs are different from each other, the optical characteristics and reliability of the product may be affected.

  An object of the present invention to solve the problems of the prior art as described above is to emit red light after exciting a nitride phosphor using light emitted from an LED without using a YAG phosphor. It is an object of the present invention to provide a novel nitride red phosphor capable of easily controlling the structure of the amount of phosphor and improving the uniformity and reproducibility.

  Another object of the present invention is to provide a method for producing the nitride red phosphor suitable for mass production because it is produced in a general gas atmosphere NPS (Normal Pressure Sintering) and does not require pulverization.

  Another object of the present invention is to provide a new white LED having high color rendering properties and luminous efficiency, and excellent thermal stability and chemical resistance by using the nitride red phosphor as a light source. It is in.

  Another object of the present invention is to provide a new white LED package having high color rendering properties and luminous efficiency by including a new white LED using the nitride red phosphor as a light source. .

In order to achieve the above object, the present invention provides a nitride red phosphor represented by the following [Formula 1].
[Formula 1]
_{Ba 2-x Re x Al y} Si 5-y N 8
(Wherein the molar ratio has values of 0.0001 ≦ x ≦ 1.0 and 0.001 ≦ y ≦ 5.0, and Re is at least one selected from rare earth elements or transition metal elements) Element.)

  The nitride red phosphor can be activated by a rare earth element.

  The excitation wavelength of the nitride red phosphor is preferably 300 to 500 nm, and the emission wavelength is preferably 500 to 800 nm.

  In the nitride red phosphor, Re is preferably one or more metals selected from the group consisting of Ce, Pr, Eu, Tb, Yb, Er, and Mn.

  In order to achieve the above object, the present invention provides a gas mixture at a temperature of 1400 to 1800 ° C. and a normal pressure after first heat-treating the dried precursor mixture at a temperature of 500 to 900 ° C. and a normal pressure gas atmosphere. A method for producing the nitride red phosphor comprising the step of secondary sintering under atmospheric conditions is provided.

  In the method for producing a nitride red phosphor, the gas is preferably nitrogen gas, argon gas, a mixed gas of hydrogen and nitrogen, or a mixed gas of carbon monoxide and carbon dioxide.

  In order to achieve the above object, according to the present invention, the nitride red phosphor is excited by a light source of an LED having a wavelength of 300 to 500 nm to generate an emission wave in a band of 500 to 800 nm, and white light is formed using this. A white LED is provided.

  In the white LED, the main wavelength of the LED light source is preferably 390 to 480 nm.

  In the white LED, the nitride red phosphor preferably has a peak wavelength of red light emitted later of 600 to 680 nm.

  In the white LED, it is preferable that Re of the nitride red phosphor uses Eu, and the molar ratios are 0.0001 ≦ x ≦ 1.0 and 0.001 ≦ y ≦ 5.0.

  In the white LED, the nitride red phosphor may be mixed with a transparent epoxy or silicon resin and applied onto a chip constituting a light source of the LED by a dispensing method.

  In the white LED, the nitride red phosphor may be mixed with a transparent epoxy or silicon resin and applied onto a chip constituting a light source of the LED by transfer molding.

  In the white LED, the nitride red phosphor may be mixed with a transparent epoxy or silicon resin and applied onto a chip constituting a light source of the light emitting diode by sputtering or vapor deposition.

  In order to achieve the above object, according to the present invention, the nitride red phosphor is excited by a light source of an LED having a wavelength of 300 to 500 nm to generate an emission wave in a band of 500 to 800 nm, and white light is formed using this. A white LED package is provided.

  In the white LED package, the package may be a bullet type.

  In the white LED package, the package may be a surface mount type.

  In the white LED package, the surface-mount white LED package preferably includes an epoxy lens.

  Since the white LED of the present invention has high color rendering properties and luminous efficiency, it can be used for lighting applications that require high color rendering properties. Related technologies such as LED manufacturing technology and phosphor manufacturing technology are related. It can greatly contribute to the activation of industry.

The nitride red phosphor represented by the following [Formula 1] according to the present invention is composed of an oxide, sulfide, nitride, or the like to which transition metal or rare earth ions are added in order to activate light emission. .
[Formula 1]
_{Ba 2-x Re x Al y} Si 5-y N 8
(Wherein the molar ratio has values of 0.0001 ≦ x ≦ 1.0 and 0.001 ≦ y ≦ 5.0, and Re is at least one selected from rare earth elements or transition metal elements) Element.)

  The nitride red phosphor according to the present invention can be used as a new phosphor having further improved thermal stability and chemical resistance by adding α-SiAION ceramic.

  The nitride red phosphor according to the present invention exhibits an absorption spectrum in the wavelength region of 300 to 500 nm, preferably 500 to 800 nm, by using the base silicon-aluminum-nitride compound, and 500 to 800 Since it exhibits excellent luminous efficiency at a broadband wavelength of preferably 520 to 700 nm, more preferably 600 to 650 nm, when used in a white LED, the composition of the amount of phosphor can be easily controlled, and uniformity and reproduction Can be improved.

  Further, by adding one or more metals selected from the group consisting of Ce, Pr, Eu, Tb, Yb, Er, and Mn to the base compound, the emission characteristics and physical characteristics of the phosphor are changed. Can be given.

  In the above [Formula 1], the addition amount x of Re is preferably 0.0001 ≦ x ≦ 1.0. However, when the x value is less than 0.0001, the amount of the activator is small. There is a problem that the wavelength conversion efficiency of the phosphor is lowered due to the decrease in luminance due to the absence of light emission. When the x value exceeds 1.0, the fluorescent material is activated by an excessively added activator. This is not preferable because there is a problem that the light extinction phenomenon occurs inside the body and the efficiency is lowered.

The method for producing the phosphor composition of the above [Formula 1] according to the present invention is not particularly limited, but a solid phase method, a liquid phase method, and a gas phase method are all possible. Are silicon nitride (Si ₃ N ₄ ), magnesium nitride (Mg ₃ N ₂ ), barium nitride (Ba ₃ N ₂ ), barium hydroxide (Ba (OH) ₂ ), aluminum nitride (AlN), aluminum hydroxide ( al (OH) _3), (nitride of a rare earth metal such as EuN), europium hydroxide (Eu (OH) europium nitride hydroxides of the rare earth metals, such as ₃₎ or europium oxide, (Eu ₂ Oxide of rare earth metal such as O ₃ ) is pulverized, mixed and dried in a glove box filled with a gas such as high purity nitrogen or argon, and the dried material is reduced to 500 By performing a primary heat treatment in a gas atmosphere at a temperature of ˜900 ° C. and a normal pressure of about atmospheric pressure, followed by secondary sintering in a gas atmosphere containing hydrogen at least 5% at 1300 to 1800 ° C. Can be manufactured.

  The gas is preferably nitrogen gas, argon gas, a mixed gas of hydrogen and nitrogen, or a mixed gas of carbon monoxide and carbon dioxide.

  The reason for performing the sintering separately from the primary and secondary is to remove impurities such as moisture, organic matter, or partially salt complex compounds contained in the mixed raw material in the region of 500 to 900 ° C. However, when the primary sintering temperature is 500 ° C. or lower, crystals are not effectively formed, and when the primary sintering temperature is 900 ° C. or higher, of the mixed components. Since an unnecessary unreacted material can be formed, the secondary sintering formation reaction is hindered, and the wavelength conversion efficiency is lowered.

  In addition, when the secondary sintering temperature is 1400 ° C. or lower, the synthesis reaction of the fluorescent material does not become normal, and there is a problem that the desired emission intensity cannot be obtained in the wavelength characteristics. Is not preferable because the fluorescent substance is melted at a high temperature and formed into a glass phase, so that the emission intensity is reduced, or volatilized at a high temperature to easily obtain a powder of a desired substance.

Currently, the commonly used CaAlSiN ₃ : Eu ⁺² phosphor is manufactured at a high temperature of 1800 to 2200 ° C. and a high pressure of 1 to 20 Mpa. There is a problem that must be crushed.

  However, the manufacturing method of the nitride red phosphor according to the technology of the present invention is not a GPS (Gas Pressure Sintering) method as in the conventional manufacturing method, but is a normal pressure gas atmosphere NPS (Normal Pressure Sintering) in a normal manufacturing process. Since there is no need for manufacturing and pulverization, the apparatus is simple and can be operated easily, so there is an advantage suitable for mass production.

White LED according to the present invention generates a release wave 500~800nm band the nitride red phosphor _{Ba 2-x Re x Al y} Si 5-y N 8 excites the LED light source of 300~500nm wavelength, Using this, white light is formed.

  The main wavelength of the light source of the white LED is preferably 390 to 480 nm, and the nitride red phosphor preferably has a peak wavelength of red light emitted later of 600 to 650 nm.

  Hereinafter, the present invention will be described in more detail with reference to the drawings.

  FIG. 7 is a schematic view illustrating a shell-type white LED package using the nitride red phosphor according to the present invention.

  Referring to FIG. 7, the white LED package 100 includes an (Al) InGaN active layer, and a sapphire substrate or a silicon carbide (SiC) substrate can be used.

  After the blue LED 110 is die-bonded to the lead frame 150, gold wire bonding 140 is performed to connect the electrodes to the outside. When the sapphire substrate is used for the gold wire bonding 140, since there are p-type and n-type electrodes on the upper part of the element, the gold wire bonding 140 is performed for each, but when using the SiC conductive substrate, once. The gold wire bonding 140 can be performed. After the gold wire bonding 140, a region 120 in which epoxy and phosphor are mixed is applied using a dispenser or an appropriate application method for white light emission.

  Next, the resultant product after coating is cured at a constant temperature so as not to flow. Thereafter, the epoxy lens 130 is configured using a mold having a desired pattern, and the bullet-type white LED lamp 100 is manufactured through the trimming and cutting process of the lead frame 150. Here, the white LED (white light emitting diode) is configured by a blue LED 110 and a region 120 in which an epoxy and a phosphor are mixed.

Here, in order to further embodying the present invention, epoxy and _{Ba 2-x Re x Al y} Si 5-y N 8 phosphor color rendering property by ratios by changing to produce a shell type lamp, the color temperature and Measure the spectrum. For example, in the case of mixing epoxy and phosphor, 0.1 g, 0.2 g, 0.3 g, 0.4 g, and 0.5 g of phosphor are added based on 100 μl of transparent epoxy and applied by a dispensing method. Make a transparent epoxy lamp.

  Further, it can be manufactured in other types of package types, but in particular, it can be manufactured in a surface mount type (SMD, SMT), and these are shown in FIG. 9 and FIG.

  FIG. 8 is a schematic view showing a surface-mounted white LED package using a blue LED according to the present invention.

Referring to FIG. 8, the blue LED 210 is die-bonded on the metal wire 270 of the PCB substrate 260, and the p-electrode and the n-electrode of the LED are bonded 240 to the metal wire 270 with a gold wire to electrically connect to the outside. Energize. _{Thereafter, Ba 2-x Re x Al} y Si 5-y N 8 phosphor 220a in an appropriate amount of the epoxy 220, a mixture of 220b, put on top of the blue LED 210. Then, the epoxy mixed with the phosphor can be molded in a dispenser type, and another method is to solidify and complete the surface-mounted white LED package 200 formed into a transfer mold. Here, the white LED is composed of an epoxy in which a blue LED 210 and a phosphor are mixed.

  FIG. 9 is a schematic view showing an epoxy lens type surface mount type white LED package according to the present invention.

  Referring to FIG. 9, the surface-mount white LED package 300 includes a PCB substrate or a ceramic substrate 360 on which metal wires 370 are attached to portions to be an anode and a cathode. And the insulator 390 and the like. The inside of the region 380 surrounding the epoxy is made of a reflective film coated with aluminum or silver, and serves to reflect light emitted from the diode upward and to surround an appropriate amount of epoxy. The purple LED 310 is die-bonded in a flip-chip form with a bonding material 340 such as a gold buffer or Au—Sn, and epoxy or silicon resin 320 in which green and red phosphors are mixed at an appropriate mixing ratio is dispensed. Here, the silicon resin 320 can be used for a high-power LED package. The silicon resin 320 can prevent thermal stress from being directly transmitted to the chip and adversely affect reliability, or can prevent a gold wire from being short-circuited due to thermal contraction or expansion. Further, by using the silicon resin 320 having a refractive index higher than that of epoxy, reflection at the interface of light emitted from the diode can be reduced and luminance can be improved.

  As described above, after the epoxy or silicon resin 320 mixed with the phosphor is applied, the epoxy lens 330 is formed thereon. At this time, the epoxy lens 330 can change the pattern according to a desired directivity angle. Here, the surface-mounted white LED is composed of a purple LED 310 and an epoxy or silicon resin 320 in which green and red phosphors are mixed at an appropriate mixing ratio.

  Hereinafter, the present invention will be described in more detail through examples and experimental examples. However, these are for explaining the present invention in more detail, and the scope of rights of the present invention is not limited by these.

Examples 1 to 5 (Production of Ba _2-x Re _x Al _y Si _5-y N ₈ phosphor)
Si, aluminum, barium and europium precursors mixed with stoichiometric ratio of Si ₃ N ₄ , AlN, Ba ₃ N ₂ , Ba (OH) ₂ , Eu (NO ₃ ) ₃ and EU ₂ O ₃ After adding a small amount of isopropanol solvent, the slurry was pulverized and mixed in a glove box filled with nitrogen gas, and then dried in a vacuum dryer in which the slurry was maintained at 80 ° C.

  After the powder thus hardened is decomposed by sieving, it is charged into an alumina reaction vessel and subjected to primary heat treatment for 5 hours under a nitrogen atmosphere at a temperature of 800 ° C. and normal pressure, and 5% hydrogen is included at 1500 ° C. The secondary sintering was performed under the normal pressure nitrogen atmosphere, and finally washed with distilled water.

  At this time, the nitride red phosphor according to the present invention was manufactured while changing the addition amount x of the active substance Eu and the addition amount y of aluminum as shown in Table 1 below.

Examples 6 to 10 (Production of Ba _2-x Re _x Pr _y Si _5-y N ₈ phosphor)
Si, aluminum, barium, and praseodymium (Pr) precursors that contain Si ₃ N ₄ , AlN, Ba ₃ N ₂ , Ba (OH) ₂ , Pr (NO ₃ ) _3, and Pr ₂ O ₃ The mixture was mixed at a ratio, and a small amount of isopropanol solvent was added. After pulverization and mixing in a glove box filled with nitrogen gas, the slurry was dried in a vacuum dryer maintained at a temperature of 80 ° C.

  The solidified powder was decomposed by sieving, charged into an alumina reaction vessel and subjected to primary heat treatment for 5 hours under a nitrogen atmosphere at a temperature of 800 ° C. and normal pressure, and 5% hydrogen was included at 1500 ° C. Then, secondary sintering was performed in a nitrogen atmosphere at normal pressure, and finally washing was performed using distilled water.

  At this time, the nitride red phosphor according to the present invention was manufactured while changing the addition amount x of the active substance Pr and the addition amount y of aluminum as shown in Table 2 below.

Experimental Example 1 (Excited emission characteristics of nitride red phosphor)
The excitation emission characteristics of the nitride red phosphor according to the present invention are shown in FIG. FIG. 3 is a graph showing characteristics of blue excited emission of the nitride red phosphor according to the present invention.

When referring to FIG. 3, while changing the composition in the nitride red phosphor _{Ba 2-x Re x Al y} Si 5-y N 8 the value of x in the range of 0.0001 to 0.4, and y by changing the value to a range of 0.001 to 5, the excitation (excitation) and emission (emission) spectrum of _{Ba 2-x Re x Al y} Si 5-y N 8 phosphor is fired at 1,300 to 1,800 ° C. The measurement results are shown. Here, the spectrum measurement was performed using a PL measurement equipment (Perkin Elmer LS55), and the graph showing the results was obtained by monitoring at the 630 nm red emission wavelength (λ _mor ) in order to confirm the optimum excitation wavelength. It is the graph which illustrated things. At this time, the spectrum of the composition by the combination of the x values shows a similar result, so it is displayed as a single line on the graph.

  Here, the maximum excitation wavelength showing the greatest intensity is 392 nm, and the x value at this time is 0.12, and the y value is 0.5.

  As a result of experiments with most other combinations, it has been shown that the excitation wavelength has a maximum value near 392 nm and has an excitation wavelength in a wide range up to 500 nm.

Experimental Example 2 (Light emission characteristics of nitride red phosphor)
The results of measuring the emission characteristics of the nitride red phosphor according to the present invention are shown in FIG. FIG. 4 is a graph showing light emission (λ _em : 630 nm) characteristics in the red region by blue light excitation (λ _ex : 460 nm) of the nitride red phosphor according to the present invention.

When referring to FIG. 4, if the x value with reference to the results of FIG. 3 in nitride red phosphor _{Ba 2-x Re x Al y} Si 5-y N 8 is 0.215, to have the highest strength And has a maximum value at 630 nm.

Emission spectrum of the nitride red phosphor _{Ba 2-x Re x Al y} Si 5-y N 8 according to the present invention, the direction of the long wavelength maximum value by the value x increases from 0.01 to 0.3 Indicated. Further, one light band can be a maximum amount at 500 to 800 nm, emission peak bandwidth is narrowed by the content of Eu in _{Ba 2-x Re x Al y} Si 5-y N 8 increases It can be confirmed that the long wavelength is indicated.

Experimental Example 3 (X-ray diffraction pattern measurement of nitride red phosphor)
The result of investigating the X-ray diffraction pattern of the nitride red phosphor according to the present invention is shown in FIG. FIG. 5 is a graph showing an X-ray diffraction pattern of the nitride red phosphor according to the present invention.

When referring to FIG. 5 shows the results of structural analysis by measuring X-ray diffraction pattern of the oxide red phosphor _{Ba 2-x Re x Al y} Si 5-y N 8. A structure having a maximum peak at 29.86 ° is shown, and such a structure is the same as the previously published CaAlSiN ₃ , M ₂ Si ₅ N ₈ (M = Ca, Sr, Ba) nitride, or MSi ₂ O. _It has a new crystal structure that is completely different from ₂ N ₂ (M = Ca, Sr, Ba) oxynitride.

Experimental Example 4 (Investigation of particle morphology of nitride red phosphor)
The result of investigating the particle morphology of the nitride red phosphor according to the present invention is shown in FIG. FIG. 6 is an electron microscope photograph of the nitride red phosphor according to the present invention.

When referring to FIG. 6, the form of the particles appear by SEM measurement of the nitride red phosphor _{Ba 2-x Re x Al y} Si 5-y N 8. It can be confirmed that fine particles having a length of about 3 to 4 μm are mainly formed, and particles of 2 μm or less are formed. Such phosphor particles are suitable for application to white LED elements because they can be easily mixed with epoxy or the like.

Generally, it is known that the average particle size of the phosphor for exciting LED is suitably 10 μm or less. Therefore, in the present invention, after being excited by the LED and light having a wavelength of 300 to 500 nm, suitable to _{Ba 2-x Re x Al y} Si 5-y N 8 phosphor that emits red light as described above A white LED or a white LED lamp can be produced by mixing at a ratio. The white LED or the white LED lamp according to the present invention includes a mixed region such as epoxy or silicon resin, and further includes a lead frame or electrode wiring for connecting the epoxy lens and the electrode to the outside.

Experimental Example 5 (Optical characteristics of nitride red phosphor)
The result of measuring the luminance of the nitride red phosphor according to the present invention is shown in FIG. FIG. 10 compares the brightness of the nitride red phosphor for blue light excitation according to the present invention with the conventional YAG product and the europium tungsten-based red phosphor product for LCD backlight (Eu ₂ W ₂ O ₉ : Eu ² ). It is a graph which shows a result.

Referring to FIG. 10, the existing normal YAG product and the europium tungsten-based red phosphor product (Eu ₂ W ₂ O ₉ : Eu ² ) for LCD backlight in the region of 610 nm or more by the excitation light of the blue light source according to the present invention. When comparing with, you can see that it has better performance.

Experimental Example 6 (Measurement of efficiency of white LED)
The result of measuring the efficiency of the white LED according to the present invention is shown in FIG. FIG. 11 is a graph showing the result of measuring the efficiency of a white LED by an experiment of a blue phosphor (460 nm) excitation red phosphor package according to the present invention.

  Referring to FIG. 11, when 460 nm is applied to R_p 2.5%, R_p 5%, and R_p 10%, all the light generated from the lamp is collected by an integrating sphere and evaluated with an integrated value. Were organized by spectrum / intensity values as shown in Table 3 below.

As a result of investigation as described above, nitride red phosphor _{Ba 2-x Re x Al y} Si 5-y N 8 constituting a white LED package according to the present invention, from that of the conventional be a novel substance which can not be compared In the case of R_p 5%, it was confirmed that the photon efficiency was 53.9% at the maximum.

  The photon efficiency can also be explained by the crystal structure of the ceramic red phosphor according to the present invention, as will be described later.

The geometrical crystal structure of the nitride ceramic phosphor is mostly orthorhombic, and in the case of an oxide phosphor, it generally has a hexagonal structure. . Ordinary nitride or oxynitrides phosphors have [Al—N] and [Si—N] ring structures based on corners, faces or corners (Si, Al) (O, N) _4. Although having a network structure, an atom having a large ionic radius is located in the central part of the basic skeleton generated by superposition of these host lattice materials, and Ce, Tb, Eu, Activation is achieved by positioning a rare earth metal such as Y.

Thus, nitride red phosphor according to the present invention is a stoichiometric compound _{(stoichiometric compound), Ba 2-} x Re x Al y Si 5-y N in ₈ Ca, Sr, Mg, Zn and Re (Ce, Pr, Eu, Tb , Yb, Er) results in optical properties are the type of _{stoichiometric} to the position of _{Ba 2-x Re x Al y} Si 5-y N in ₈ Ba The M element and the Re element are structurally stable in a wide wavelength region, and the photon (photon) absorption amount is maximized by making 1-2 or more interstitial or substitutional solid solutions. An optimal structure can be obtained.

As described above, the present invention _is, by exciting the _{Ba 2-x Re x Al y} Si 5-y N 8 phosphor at 460nm wavelength, the efficiency of the white diode that uses the LED of blue and ultraviolet light foundation It is improved so that high color rendering properties can be obtained, and thereby various colors can be realized.

  As described above, the embodiments and experimental examples of the present invention have been described. However, the present invention is not limited to the above-described embodiments, and can be modified into various different forms, and the technical field to which the present invention belongs. Therefore, those who have ordinary knowledge can implement in different specific forms without changing the technical idea and essential features of the present invention. Therefore, it should be understood that the above embodiments are illustrative in all aspects and not limiting.

It is a distribution map of the wavelength spectrum of white LED by a prior art. It is a CIE chart of white LED by a prior art. 4 is a graph showing ultraviolet light excitation emission characteristics of the nitride red phosphor according to the present invention. 4 is a graph showing emission characteristics in a red region of 630 nm by blue light (460 nm) excitation of the nitride red phosphor according to the present invention. It is a graph which shows the X-ray-diffraction pattern of the nitride red fluorescent substance by this invention. It is a photograph of the electron microscope of the nitride red phosphor according to the present invention. 1 is a schematic diagram illustrating a shell-type white LED package using a nitride red phosphor according to the present invention. 1 is a schematic diagram showing a surface-mounted white LED package using a blue LED according to the present invention. 1 is a schematic view showing an epoxy lens type surface mount type white LED package according to the present invention; FIG. Blue light excitation for nitride red phosphor according to the present invention with conventional YAG products and LCD backlight europium tungsten based red phosphors Product: is a graph depicting the results of comparing the brightness of the _{(Eu 2 W 2 O 9 Eu} 2) . It is a graph which shows the result of having measured the efficiency of white LED by the package experiment of the red fluorescent substance for blue light excitation by this invention.

Explanation of symbols

100 ... White LED package 110, 210 ... Blue LED
120, 380 ... area 130, 330 ... epoxy lens 200, 300 ... surface mount type white LED package 220 ... epoxy 220a, 220b ... phosphor 310 ... purple LED
320 ... Silicone resin

Claims (17)

Nitride red phosphor represented by the following formula 1:
[Formula 1]
_{Ba 2-x Re x Al y} Si 5-y N 8
(Wherein the molar ratio has values of 0.0001 ≦ x ≦ 1.0 and 0.001 ≦ y ≦ 5.0, and Re is at least one selected from rare earth elements or transition metal elements) Element.)   The nitride red phosphor according to claim 1, wherein the nitride phosphor is activated by a rare earth element.   The nitride red phosphor according to claim 1, wherein the nitride phosphor has an excitation wavelength of 300 to 500 nm and an emission wavelength of 500 to 800 nm.   2. The nitride red phosphor according to claim 1, wherein the Re is one or more metals selected from the group consisting of Ce, Pr, Eu, Tb, Yb, Er, and Mn.   Including a step of subjecting the dried mixture of precursors to primary heat treatment under a gas atmosphere condition at a temperature of 500 to 900 ° C. and atmospheric pressure, and then performing a secondary sintering under a gas atmosphere condition of 1400 to 1800 ° C. The method for producing a nitride red phosphor according to claim 1.   6. The method for producing a nitride red phosphor according to claim 5, wherein the gas is nitrogen gas, argon gas, a mixed gas of hydrogen and nitrogen, or a mixed gas of carbon monoxide and carbon dioxide.   The nitride red phosphor according to claim 1 is excited by a light source of a light emitting diode having a wavelength of 300 to 500 nm to generate an emission wave in a band of 500 to 800 nm, and white light is formed using this. White light emitting diode.   The white light emitting diode according to claim 7, wherein a main wavelength of the light emitting diode light source is 390 to 480 nm.   The white light emitting diode according to claim 7, wherein the nitride red phosphor has a peak wavelength of red light emitted later of 600 to 680 nm.   8. The white color according to claim 7, wherein Eu of the nitride red phosphor uses Eu and molar ratios are 0.0001 ≦ x ≦ 1.0 and 0.001 ≦ y ≦ 5.0. Light emitting diode.   The white light emitting diode according to claim 7, wherein the nitride red phosphor is mixed with a transparent epoxy or silicon resin and applied onto a chip constituting the light emitting diode light source by a dispensing method. .   The white light emitting diode according to claim 7, wherein the nitride red phosphor is mixed with a transparent epoxy or silicon resin and applied onto a chip constituting a light source of the light emitting diode by transfer molding. .   8. The nitride red phosphor is mixed with a transparent epoxy or silicon resin and applied onto a chip constituting a light source of the light emitting diode by sputtering or vapor deposition. White light emitting diode.   The nitride red phosphor according to claim 1 is excited by a light source of a light emitting diode having a wavelength of 300 to 500 nm to generate an emission wave in a band of 500 to 800 nm, and white light is formed using this. White light emitting diode package.   15. The white light emitting diode package according to claim 14, wherein the package is a shell type.   15. The white light emitting diode package according to claim 14, wherein the package is a surface mount type. The white light-emitting diode package according to claim 16, wherein the surface-mounted white light-emitting diode package has an epoxy lens.