JP2009079069A - Carbonitride-based fluorophor and light-emitting device using the same and method for producing carbonitride-based fluorophor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a carbonitride-based fluorophor having high light-emitting characteristics in a wide temperature range, to provide a light-emitting device using the same, and to provide a method for producing the carbonitride-based fluorophor. <P>SOLUTION: This carbonitride-based fluorophor absorbing near ultraviolet rays to emit rays having yellow to green colors, is characterized by being represented by the following general formula: A<SB>u</SB>B<SB>v</SB>Si<SB>w</SB>C<SB>x</SB>N<SB>y</SB>O<SB>z</SB>:Eu<SP>2+</SP>, wherein, A is Sr or Ba; B is Y or Lu; Si is silicon; C is carbon; N is nitrogen; O is oxygen; Eu is europium; 1≤u+v≤3, 0.5≤u≤1.5, 0.5≤v≤1.5, 2≤w≤6, 0.01≤x≤8, 0.05≤y≤8, 0.01≤z≤8. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a carbonitride-based phosphor used for lighting such as a light-emitting diode and a fluorescent lamp, a display, a backlight for liquid crystal, and the like, a light-emitting device using the same, and a method for producing a carbonitride-based phosphor. The present invention relates to a carbonitride-based phosphor that emits yellow to green light when excited by near-ultraviolet light, a light-emitting device using the same, and a method for producing a carbonitride-based phosphor.

  By combining light source light emitted from the light emitting element and a wavelength conversion member that can be excited by this and emit light of a different hue from the light source light, light of various wavelengths can be emitted based on the principle of color mixing of light. Light emitting devices have been developed.

  For example, there are the following two methods for emitting white light. (1) Exciting a yellow light emitting phosphor with blue light emitted from a light emitting element in a short wavelength side region of visible light. As a result, yellow light partially converted in wavelength and blue light not converted are mixed. As a result, two colors having a complementary color relationship are mixed and appear as white to the human eye. (2) The R • G • B phosphor is excited by light in the short wavelength region from ultraviolet to visible light emitted from the light emitting element. As a result, the three colors are mixed and emitted as white light.

As an example of such a wavelength conversion member, the phosphor described in Non-Patent Document 1 is a nitride phosphor containing carbon, which absorbs blue light and emits yellow light. Non-Patent Document 2 discloses a compound similar to the composition of the phosphor of Non-Patent Document 1 in terms of a structure containing nitrogen and carbon.
Hongchuan Zhang, Takashi Horikawa, and Ken-ichi Machida, Journal of The Electrochemical Society, 153 (7) H151-H154 (2006) K. Liddell, DPThompson, SJTeat, Journal of the European Ceramic Society 25 (2005) 49-54

  On the other hand, in recent years, light-emitting devices having the above-described semiconductors have attracted attention as next-generation lighting with lower power consumption and longer life, and high-quality light emission with further improved brightness and light output and weather resistance. Improvement to the equipment is required. However, the phosphor of Non-Patent Document 1 has low luminance and is difficult to put into practical use.

  Furthermore, in order to respond to the recent severe demand for higher output, the input power to the light emitting element is increasing, and accordingly, the temperature in the element and in the light emitting device tends to rise. In general, the fluorescence intensity decreases as the temperature of the medium increases. This is because as the temperature rises, intermolecular collision increases and potential energy loss is caused by non-radiative transition deactivation. Therefore, an improvement in temperature characteristics is also expected in the wavelength conversion member disposed in the vicinity of the light emitting element that can be a heat source.

  As a result of intensive studies, the present inventors have found a novel compound. A main object of the present invention is to provide a carbonitride-based phosphor having high emission characteristics in a wide temperature range, a light-emitting device using the same, and a method for producing the carbonitride-based phosphor.

The carbonitride-based phosphor according to the first invention is a carbonitride-based phosphor activated with europium, which absorbs near ultraviolet rays and emits yellow to green light, and is represented by the following general formula: Let v, w, x, y, z be the following ranges.
A _u B _v Si _w C _x N _y O _z : Eu ²⁺
A is Sr or Ba, B is Y or Lu, Si is silicon, C is carbon, N is nitrogen, O is oxygen, and Eu is europium.
1 ≦ u + v ≦ 3, 0.5 ≦ u ≦ 1.5, 0.5 ≦ v ≦ 1.5, 2 ≦ w ≦ 6, 0.01 ≦ x ≦ 8, 0.05 ≦ y ≦ 8, 0. 01 ≦ z ≦ 8

The carbonitride phosphor according to the second invention has a composition formula of SrYSi ₄ (C, N, O) _7-δ : Eu or SrLuSi ₄ (C, N, O) _7-δ : Eu.

A carbonitride-based phosphor according to the third invention is a carbonitride-based phosphor activated by europium and absorbing near ultraviolet rays to emit yellow to green light, and is represented by the following general formula: t, u, v, w, x, y, z can be in the following ranges.
_{A u B v Si w Al t} C x N y O z: Eu 2+
A is Sr or Ba, B is Y or Lu, Si is silicon, Al is aluminum, C is carbon, N is nitrogen, O is oxygen, and Eu is europium.
1 ≦ u + v ≦ 3, w + t = 4, 0.5 ≦ u ≦ 1.5, 0.5 ≦ v ≦ 1.5, 3.90 ≦ w ≦ 3.99, 0.01 ≦ x ≦ 7, 05 ≦ y ≦ 7, 0.01 ≦ z ≦ 7, 0.01 ≦ t ≦ 0.1

  In the carbonitride-based phosphor according to the fourth invention, the molar ratio of A / B can be set to 0.45 to 3.0.

  In the carbonitride phosphor according to the fifth aspect of the invention, oxygen is contained in the composition in an amount of 0.5 wt% to 5 wt%.

  In the carbonitride phosphor according to the sixth aspect of the invention, the C / N molar ratio is set to 0.05 to 0.30.

  The carbonitride phosphor according to the seventh aspect of the present invention contains 0.5 wt% or more and 5 wt% or less of carbon.

  In the carbonitride phosphor according to the eighth aspect of the invention, the average particle size of the phosphor is 2 μm or more and 20 μm or less.

  A light-emitting device according to a ninth aspect of the invention is an excitation light source having a first emission spectrum that emits near-ultraviolet light, and one or two that emit at least a part of the first emission spectrum and emit a second emission spectrum. A light emitting device having at least one type of wavelength conversion member, wherein the wavelength conversion member has the carbonitride-based phosphor according to any one of the first to eighth inventions.

In the method for producing a carbonitride phosphor according to the tenth aspect of the present invention, each of the raw materials containing an alkaline earth metal element, a rare earth element, europium, carbon, silicon, and nitrogen has a C / N molar ratio of 0.05 to A step of weighing and mixing to 0.30, and a step of firing and further reducing the mixed raw material.
A _u B _v Si _w C _x N _y O _z : Eu ²⁺
A is Sr or Ba, B is Y or Lu, Si is silicon, C is carbon, O is oxygen, N is nitrogen, and Eu is europium.
1 ≦ u + v ≦ 3, 0.5 ≦ u ≦ 1.5, 0.5 ≦ v ≦ 1.5, 2 ≦ w ≦ 6, 0.01 ≦ x ≦ 8, 0.05 ≦ y ≦ 8, 0. 01 ≦ z ≦ 8

  The phosphor of the present invention is a carbonitride-based phosphor containing an alkaline earth metal and a rare earth in its composition, and has high emission luminance in a wide temperature range. In addition, it has a feature that can suppress a decrease in light emission luminance particularly in a high temperature range. Thereby, in the light emitting device equipped with the carbonitride-based phosphor described above, it is possible to realize emitted light having excellent temperature characteristics even when the temperature inside the device is increased by driving with a large current.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the embodiment described below exemplifies a carbonitride-based phosphor, a light emitting device using the same, and a carbonitride-based phosphor manufacturing method for embodying the technical idea of the present invention. Therefore, the present invention does not specify the carbonitride phosphor, the light emitting device using the same, and the method for producing the carbonitride phosphor as follows. In addition, the member shown by the claim is not what specifies the member of embodiment. In particular, the dimensions, materials, shapes, relative arrangements, and the like of the component parts described in the embodiments are not intended to limit the scope of the present invention unless otherwise specified, and are merely explanations. It is just an example. Note that the size, positional relationship, and the like of the members shown in each drawing may be exaggerated for clarity of explanation. Furthermore, in the following description, the same name and symbol indicate the same or the same members, and detailed description thereof will be omitted as appropriate. Furthermore, each element constituting the present invention may be configured such that a plurality of elements are constituted by the same member and the plurality of elements are shared by one member, and conversely, the function of one member is constituted by a plurality of members. It can also be realized by sharing.

  The relationship between the color name and chromaticity coordinates, the relationship between the wavelength range of light and the color name of monochromatic light, and the like comply with JIS Z8110. Specifically, 380 nm to 455 nm is blue purple, 455 nm to 485 nm is blue, 485 nm to 495 nm is blue green, 495 nm to 548 nm is green, 548 nm to 573 nm is yellow green, 573 nm to 584 nm is yellow, 584 nm to 610 nm is yellow red , 610 nm to 780 nm is red.

(Phosphor)
The phosphor according to the embodiment of the present invention is a carbonitride phosphor containing an alkaline earth metal and a rare earth, and absorbs near ultraviolet light or blue light with europium as a light emission center and emits yellow to green light. To do. The phosphor has a general formula of A _u B _v Si _w C _x N _y O _z : Eu ²⁺ (1 ≦ u + v ≦ 3, 0.5 ≦ u ≦ 1.5, 0.5 ≦ v ≦ 1.5). , 2 ≦ w ≦ 6,0.01 ≦ x ≦ 8,0.05 ≦ y ≦ 8,0.01 ≦ z ≦ 8), _{or, A u B v Si w Al} t C x N y O z: Eu ²⁺ (1 ≦ u + v ≦ 3, w + t = 4, 0.5 ≦ u ≦ 1.5, 0.5 ≦ v ≦ 1.5, 2 ≦ w ≦ 6, 0.01 ≦ x ≦ 7, 0.05 ≦ y ≦ 7, 0.01 ≦ z ≦ 7, 0.01 ≦ t ≦ 0.1), A is Sr or Ba, B is Y or Lu, Si is silicon, and C is carbon , N is nitrogen, O is oxygen, and Eu is europium. Moreover, oxygen may contain in a composition. In addition, the phosphor may contain various additive elements as flux and, if necessary, boron. Thereby, it becomes possible to promote solid-phase reaction and form particles of uniform size. These composition ratios are based on the final product.

  In addition, the carbonitride-based phosphor according to the embodiment of the present invention absorbs light in the short-wavelength side region of near-ultraviolet light or visible light, and the phosphor has a longer wavelength side than the emission peak wavelength of excitation light. It has an emission peak wavelength. The light in the short wavelength region of visible light is mainly in the blue light region. Here, the short wavelength region from near ultraviolet to visible light in this specification refers to a region near 240 nm to 500 nm. As the excitation light source, one having an emission peak wavelength at 240 nm to 450 nm can be used. Among these, it is preferable to use an excitation light source having an emission peak wavelength at 300 nm to 420 nm. In particular, it is preferable to use an excitation light source having a wavelength of 360 nm to 420 nm that is used in semiconductor light emitting devices. This is because a phosphor with high luminous efficiency can be provided by using an excitation light source in this range. Further, by using a semiconductor light emitting element as an excitation light source, a stable light emitting device with high efficiency, high output linearity with respect to input, and strong against mechanical shock can be obtained.

  Moreover, it is preferable that at least a part of the carbonitride-based phosphor has a crystal. For example, since the structure of a glass body (amorphous) is loose, unless the reaction conditions in the production process can be controlled so as to be strictly uniform, the component ratio in the phosphor is not constant, and chromaticity unevenness occurs. Arise. On the other hand, the carbonitride-based phosphor according to the present embodiment is not a glass body but a powder or granule having crystallinity, so that it is easy to manufacture and process. Further, since this phosphor can be uniformly dissolved in an organic medium, it is easy to adjust the light emitting plastic and the polymer thin film material. Specifically, the carbonitride phosphor according to the present embodiment has at least 50% by weight, more preferably 80% by weight or more of crystals. This indicates the proportion of the crystalline phase having luminescent properties, and if it has a crystalline phase of 50% by weight or more, light emission that can withstand practical use can be obtained. Therefore, the more crystal phases, the better. As a result, the emission luminance can be increased and processing can be facilitated.

In the carbonitride-based phosphor according to the embodiment of the present invention, europium Eu, which is a rare earth, becomes the emission center. However, it is not limited to only europium, and a part of which is replaced with another rare earth metal or alkaline earth metal and co-activated with Eu can also be used. Eu ^2+, which is a divalent rare earth ion, exists stably if an appropriate matrix is selected, and has the effect of emitting light.

(Particle size)
The particle size of the carbonitride phosphor used in the light emitting device is preferably in the range of 1 μm to 20 μm, more preferably 2 μm to 15 μm. Moreover, it is preferable that the phosphor having this average particle diameter value is contained frequently. This is because a phosphor having a particle size in the above range has high light absorptance and conversion efficiency. As described above, by using a phosphor having a small variation in particle size and particle size distribution, color unevenness is further suppressed, and a light emitting device having a good color tone can be obtained.

(Phosphor material)
In addition, the carbonitride phosphor according to the present invention is manufactured by mixing various phosphor raw materials in a wet or dry manner. As phosphor raw materials, alkaline earth metals of Mg, Ca, Sr, Ba, rare earths of Sc, Y, La, Gd, Tb, Yb, Lu, Si, Eu, C, N and, if necessary, additional elements, Single or individual compounds are used. Each raw material will be described below.

(Alkaline earth metal)
The alkaline earth metal having a phosphor composition is preferably a carbonate, but a simple substance or a compound such as an imide compound or an amide compound can also be used. In addition, the alkaline earth metal as a raw material can be partially replaced with another alkaline earth metal or an alkali metal. Thereby, the peak of the emission wavelength of the carbonitride phosphor can be adjusted. The raw material is preferably purified. Thereby, since a purification process is not required, the manufacturing process of the phosphor can be simplified, and an inexpensive carbonitride-based phosphor can be provided.

  Moreover, the rare earth of a phosphor composition can use a simple substance, a halogen salt, an oxide, carbonate, a phosphate, and a silicate.

Furthermore, Si of the phosphor composition is preferably a nitride compound, but an imide compound, an amide compound, or the like can also be used. For example, Si ₃ N ₄ , Si (NH ₂ ) ₂ , Mg ₂ Si, etc. On the other hand, by using only Si alone, a carbonitride-based phosphor that is inexpensive and has good crystallinity can be obtained. The purity of the raw material Si is preferably 2N or higher, but may contain different elements such as Li, Na, K, B, and Cu. Furthermore, a part of Si can be substituted with Al, Ga, In, and Tl. Further, Si of the phosphor composition may be replaced with Ge, Sn, Ti, Zr, or Hf.

On the other hand, Al having a phosphor composition is preferably used alone, but a part thereof can be substituted with Group III elements Ga, In, V, Cr, and Co. However, a carbonitride-based phosphor that is inexpensive and has good crystallinity is obtained by using only Al. However, Al nitride or Al oxide may be used. Specifically, aluminum nitride AlN and aluminum oxide Al ₂ O ₃ can be used. It is better to use purified materials, but commercially available products may be used, which can simplify the process.

In addition, as C of the phosphor composition, single carbon such as graphite and amorphous carbon, SiC, CaC ₂ , Al ₃ C ₄ carbide, other organic substances containing carbon, polymer, and the like can be used.

Further, Eu of the activator is preferably used alone, but a part of Eu is Sc, Y, La, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb. , Lu, etc. Moreover, when using the mixture which requires Eu, a compounding ratio can be changed as desired. Thus, by replacing a part of Eu with another element, the other element acts as a co-activation. As a result, the color tone can be changed, and the light emission characteristics can be adjusted. Europium has mainly divalent and trivalent energy levels, but carbonitride-based phosphors use Eu ²⁺ as an activator for the base, for example, an alkaline earth metal element.

Further, a Eu compound may be used as a raw material. In this case, it is better to use a purified raw material, but a commercially available product may be used. Specifically, europium oxide Eu ₂ O ₃ , metal europium, europium nitride, or the like can be used as the Eu compound. The raw material Eu may be an imide compound or an amide compound. Europium oxide preferably has a high purity, and commercially available products can also be used. The phosphor according to the embodiment of the present invention uses divalent Eu as the center of light emission, but divalent Eu is easily oxidized and is generally commercially available with a composition of trivalent Eu ₂ O ₃ .

  Furthermore, the element to be added as necessary is usually added as an oxide or an oxide hydroxide, but is not limited to this, and may be a metal, nitride, imide, amide, or other inorganic salt, Moreover, the state previously contained in the other raw material may be sufficient. Each raw material has an average particle size of about 0.1 μm or more and 15 μm or less, more preferably about 0.1 μm to 10 μm. It is preferable from the viewpoint of diameter control and the like, and when the particle diameter is not less than the above range, it can be achieved by pulverizing in a glove box in an argon atmosphere or a nitrogen atmosphere.

  Moreover, oxygen may be contained in the composition of the carbonitride phosphor according to the embodiment of the present invention. It is considered that oxygen is introduced from various oxides as raw materials, the raw materials are oxidized during firing, or adheres to and mixes with the phosphor after generation. In general, by controlling the molar ratio of oxygen in the composition, it is possible to change the crystal structure of the phosphor and shift the emission peak wavelength of the phosphor. On the other hand, from the viewpoint of luminous efficiency, it is preferable that the concentration of oxygen contained in the phosphor is small, and it is preferable that the oxygen concentration be 0.5 wt% or more and 5 wt% or less with respect to the mass of the product phase.

  A flux such as boron can be added to the carbonitride-based phosphor according to the embodiment of the present invention. In general, many carbonitride-based phosphors have a high melting point, and it is difficult for a liquid phase to form when a solid-phase reaction occurs, and the reaction does not proceed smoothly. However, in the case of containing boron, the liquid phase formation temperature is lowered and the liquid phase is likely to be generated, so that the reaction is promoted, and further, the individual phase reaction proceeds more uniformly, and the light emission characteristics are excellent. It is considered that a phosphor can be obtained. The molar concentration of boron added to the carbonitride phosphor is 0.5 mol or less, and preferably 0.3 mol or less. Furthermore, it is set to 0.001 mol or more. More preferably, the molar concentration of boron is 0.001 or more and 0.2 or less. This is because if the concentration is within this range, the above-described effects can be obtained, and the sintering does not become intense, and the light emission characteristics are not deteriorated in the crushing step. Since a boron compound is a substance having a high thermal conductivity, it is presumed that, when added to the raw material, the temperature distribution of the raw material during firing becomes uniform, promotes the individual phase reaction, and improves the light emission characteristics. As an addition method, it is possible to add and mix together at the time of mixing raw materials.

Boron, boride, boron nitride, boron oxide, borate, etc. can be used as the boron material of the phosphor. Specific examples of boron added to the phosphor material include B, BN, H ₃ BO ₃ , B ₂ O ₃ , BCl ₃ , SiB ₆ , and CaB ₆ . A predetermined amount of these boron compounds is weighed and added to the raw material.

(Phosphor production method)
The production method of the divalent europium activated carbonitride-based phosphor of the present invention will be described using the above raw materials as starting materials.
1. After weighing the alkaline earth metal element, the trivalent rare earth element, Si, C, and Eu starting materials, and the flux as appropriate so as to obtain a predetermined composition, and sufficiently pulverizing and mixing, Add absolute ethanol to form a slurry. The starting material may be an oxide or another compound that can become an oxide at a certain temperature or higher. That is, carbonates, nitrates, sulfates, halides, hydroxides, and the like can be selected.
2. After the mixed raw materials are dried, they are packed in a BN (boron nitride) crucible and fired at about 1600 ° C. for 16 hours in a reducing atmosphere. The reducing atmosphere can be an atmosphere containing at least one of nitrogen, hydrogen, argon, carbon dioxide, carbon monoxide, and ammonia. However, firing can be performed in a reducing atmosphere other than these.
3. A desired phosphor powder is obtained by pulverizing, dispersing, and sieving the obtained fired product.

Example 1
The target carbonitride-based phosphor can be obtained by the above manufacturing method. Specifically, as an example of the carbonitride-based phosphor according to the present invention, a description will be given using the method for producing SrYSi ₄ (C, N, O) _7-δ : Eu in Example 1. However, the following examples illustrate phosphors for embodying the technical idea of the present invention, and the present invention does not specify phosphors as described below.

SrCO ₃ which is a carbonate of Sr, Y ₂ O ₃ which is an oxide of Y, silicon nitride Si ₃ N ₄ , europium oxide Eu ₂ O ₃ and graphite powder are used. The phosphor of the present invention limits the charged molar ratio of C / N to a specific ratio, that is, 0.05 to 0.25. This molar ratio is determined by mixing Si ₃ N ₄ and graphite mixed as raw materials. The molar ratio can be specified. The raw materials and, if necessary, the compound of the additive element are weighed and mixed so as to be in the above range. This mixing can also be done dry.
The following powders were weighed as the phosphor material of Example 1.
Graphite powder ... 0.86g
Strontium carbonate ... 2.86g
Yttrium oxide ... 2.30g
Silicon nitride ... 3.81g
Europium oxide ... 0.18g

The above mixture is packed in a BN crucible and fired in a nitrogen atmosphere containing hydrogen and / or ammonia. For firing, a tubular furnace, a small furnace, a high-frequency furnace, a metal furnace, or the like can be used. The firing temperature can be in the range of 1200 ° C to 2000 ° C, but the firing temperature of 1400 ° C to 1800 ° C is preferred. For firing, it is preferable to use one-stage firing in which the temperature is gradually raised and firing is performed at 1500 ° C. to 1700 ° C. for several hours, but the first-stage firing is performed at 800 ° C. to 1000 ° C. Two-stage baking (multi-stage baking) in which the second baking is performed at 1500 ° C. to 1700 ° C. can also be used. The phosphor material is preferably fired using a BN crucible or boat. However, other than this, a crucible such as graphite, alumina (Al ₂ O ₃ ), or Mo material may be used.

The target phosphor can be obtained by firing. The elemental analysis results and emission characteristics of the carbonitride phosphor according to Example 1 are shown in Table 1, and examples of reaction formulas are shown in Chemical Formula 1, respectively. The amount of C and the C / N molar ratio in the table are values calculated from the theoretical amount of C and N remaining in the compound after converting O ₂ of the oxide (carbonate) raw material to CO ₂ .

  However, the above chemical formula is a theoretical formula, and in reality, O (oxygen) cannot be completely removed and does not become 0 (zero), and thus does not indicate the actual composition ratio of the compounds. The chemical formula from the measured values is shown below.

  δ represents a deviation from a theoretical value that can be considered from actual measurement data. Moreover, since O / C / N is contained and the coefficient of each composition cannot be simplified, the coefficient in the chemical formula is omitted.

  However, this composition is a representative composition estimated from the blending ratio, and has sufficient characteristics to withstand practical use in the vicinity of the ratio. The phosphor manufactured in Example 1 had a C / N molar ratio of 0.20 and a C content of 3.55 wt%.

(Comparative example)
On the other hand, the phosphor of the comparative example is a phosphor having a general formula of Y ₂ Si ₄ N ₆ C: Ce, which has Ce as an emission center, does not include an alkaline earth metal in its composition, and contains only rare earth. It is a nitride phosphor. On the other hand, the phosphors of Examples 1 to 24 are carbonitride phosphors having an emission center of Eu and an alkaline earth metal and a rare earth.

(Examples 2 to 4)
Further, phosphors of Examples 2 to 4 were manufactured in the same manner as Example 1 except that the C amount was as shown in Table 1 above. Table 1 shows the results of elemental analysis and light emission characteristics. As shown in the light emission characteristics of Table 1, in the phosphors of Examples 1 to 4, an increase in luminance was confirmed in any case as compared with the phosphor of the comparative example. Specifically, in the phosphor of the present invention having a C / N charging molar ratio of 0.05 to 0.25, the luminance was improved by 5.80 to 25.7 as compared with the comparative example. In addition, the phosphor composed of the C / N molar ratio contains 2.1 wt% or more and 3.55 wt% or less of carbon by elemental analysis, that is, the present invention contains carbon in the above range. It has been demonstrated that the phosphor has suitable light emission characteristics with high brightness as compared with the comparative example. In addition, in the phosphors of Examples 1 to 4, an emission spectrum when excited with an excitation wavelength of 400 nm is shown in FIG. 1, a reflection spectrum is shown in FIG. 2, and an excitation spectrum is shown in FIG. Furthermore, a 1000 times magnified photograph of the phosphor of Example 1 is shown in FIG. 16 (a), and a 5000 times magnified photograph is shown in FIG. 16 (b). Moreover, the X-ray-diffraction figure which concerns on the fluorescent substance of Examples 1-4 is shown in FIG. Comparing FIG. 17 with the X-ray diffraction pattern of Non-Patent Document 2, it can be seen that the patterns are almost the same, and the composition of this example is a single composition and has the same structure.

  Further, in the phosphor of the present invention, at least a part of Sr can be replaced with other Group II elements such as Mg, Ca, Ba and the like. Furthermore, at least a part of the rare earth Y, which is the phosphor composition, can be replaced with other rare earth elements such as Sc, La, Gd, Tb, Yb, and Lu to obtain a carbonitride phosphor. In addition, with regard to Eu, which is an activator and a luminescent center, La, Ce, Gd, Tb, Dy, Ho, Er, Tm, Lu, etc. may be substituted for various rare earths or in addition to Eu. A carbonitride-based phosphor containing a rare earth element can be obtained. As described above, a carbonitride-based phosphor that is inexpensive and has good crystallinity can be obtained.

(Particle size)
The particle size of the carbonitride phosphor is preferably in the range of 2 μm to 20 μm. A phosphor having a particle size smaller than 2 μm tends to form an aggregate. On the other hand, a phosphor having a particle size range of 2 μm to 20 μm has a high light absorption rate and conversion efficiency. In this manner, by including a phosphor having a large particle diameter having optically excellent characteristics in a light emitting device described later, the issuing efficiency of the light emitting device is improved.

Here, the particle size is F.I. S. S. S. No. (Fisher Sub Sieve Sizer's No.) refers to the average particle size obtained by the air permeation method. Specifically, in an environment with an air temperature of 25 ° C. and a humidity of 70%, a sample of 1 cm ³ is weighed and packed in a special tubular container, then a constant pressure of dry air is flowed, and the specific surface area is read from the differential pressure. It is a value converted into an average particle diameter. The average particle diameter of the phosphor used in the present embodiment is preferably in the range of 2 μm to 20 μm. Moreover, it is preferable that the phosphor having this average particle diameter value is contained frequently. Further, the particle size distribution is preferably distributed in a narrow range. As described above, by using a phosphor having a small variation in particle size and particle size distribution, color unevenness is further suppressed, and a light emitting device having a good color tone can be obtained.

(Examples 5 to 8)
Further, in the carbonitride-based phosphors of Examples 5 to 8 represented by the composition formula MLnSi ₄ (C 1 _, N) ₇ : Eu ²⁺ (M = Sr or Ba, Ln = Y or Lu), M and Ln are as follows: The production method was the same as in Example 1 except that the raw materials were adjusted so as to be composed of the alkaline earth metal (M) and rare earth (Ln) shown in Table 2, and the C amount was 1.0 mol. However, this C amount is a theoretical charge amount and represents the amount of C remaining in the compound when O (oxygen) is removed as CO ₂ . In addition, Table 2 shows the elemental analysis results of the phosphors in Examples 5 to 8, and Table 3 shows chemical formulas converted from the analysis values.

  From the elemental analysis results shown in Table 3, the phosphors of Examples 5 to 8 contain 2.1 wt% or more and 3.4 wt% or less of carbon, and the C / N ratio is 0.194 to less than the analysis value. 0.274. That is, the phosphors of Examples 5 to 8 have a higher C content than the phosphor of Comparative Example 1 (C / N ratio 0.170). Moreover, in M / Ln ratio by an analytical value, it was 0.93-0.94.

  Moreover, the X-ray diffraction patterns of Examples 5 and 6 are shown in FIG. 18, and the X-ray diffraction patterns of Examples 7 and 8 are shown in FIG. 18 and 19, it can be seen that even when the combination of Sr, Ba, Lu, and Y, which are phosphor compositions, is changed, only the peak position is shifted, and a single composition having the same structure is obtained. Furthermore, the light emission characteristics of the phosphors in Examples 5 to 8 are shown in Table 4. In addition, Example 1 in Table 1 and Example 5 in Table 2 are carbonitride-based phosphors having the same structure. In addition, FIG. 4 shows the emission spectrum of the phosphors of Examples 5 to 8 when excited with the excitation wavelength of 400 nm, FIG. 5 shows the reflection spectrum, and FIG. 6 shows the excitation spectrum.

  The carbonitride-based phosphors composed of combinations of Sr or Ba, which are alkaline earth metals, and Y or Lu, which are rare earths, particularly when Sr is used as the alkali metal (Examples 5 and 6), The brightness was higher than that of the phosphor of the comparative example, and a favorable result was obtained. Further, Table 5 shows the relative luminance at 100 ° and 200 ° when the luminance at room temperature of the comparative example and Examples 5 to 8 is used as a reference.

  From Table 5, as compared with the phosphor of the comparative example, the phosphors of Examples 5 to 8 were comparable or significantly improved in luminance at both 100 ° and 200 °. In particular, in a carbonitride phosphor having an Sr composition in an alkali metal, the relative luminance at 100 ° is improved by 7.7% to 13.8% as compared to the comparative example, and further at 17.1 at 200 °. % To 22.2% improvement was seen. As shown in the light emission characteristics of Tables 1 to 5, the phosphor of the present invention has a reduction in luminance in a high temperature range in addition to high luminance at room temperature, compared to the phosphor of the comparative example, It can be said that it is a phosphor excellent in temperature characteristics. In particular, if the C / N charge molar ratio is 0.05 or more and 0.25 or less, or if the C / N molar ratio from elemental analysis is 0.1 to 0.3, the above-described features are obtained. The above-mentioned remarkable effect is acquired by making the content molar ratio of C / N more preferably 0.19-0.25, still more preferably 0.20-0.245.

(Examples 9 to 14)
Further, the phosphors of Examples 9 to 14 have a composition represented by SrYSi ₄ (C, N, O) _7-δ : Eu, and the content of Eu serving as the emission center is changed as shown in Table 6. Except for making it, it manufactured like Example 1. Table 6 shows the Eu amount (mol) in each example and the emission characteristics of the corresponding phosphors.

  As shown in Table 6, there was a variation in relative luminance as the Eu amount increased or decreased. In particular, the relative luminance was good when the Eu amount was around 0.05 to 0.15, and in this case, the luminance exceeded the comparative example. Moreover, in the phosphors of Examples 9 to 14, the emission spectrum when excited by the excitation wavelength of 400 nm is shown in FIG. 7, the reflection spectrum is shown in FIG. 8, and the excitation spectrum is shown in FIG.

(Examples 15 to 19)
In addition, the carbonitride-based phosphor according to Example 1 can substitute a part of Si, which is the composition, with Al, Ga, In, and Tl. The carbonitride-based phosphors of Examples 15 to 19 are represented by the general formula SrY (Si _1-δ Al _δ ) ₄ N ₇ : Eu, and a part of Si is substituted with Al. The phosphors of Examples 15 to 19 are the same as Example 1 except that Al ₂ O ₃ which is an oxide of Al or nitride AlN obtained by a direct nitriding method or the like is mixed at the time of raw material mixing. It was purified through the manufacturing process. Table 7 shows the Al content and emission characteristics of each phosphor.

  As shown in Table 7, there was almost no shift in the peak wavelength due to 0.01 to 0.10 mixing of the Al amount (mol), and a stable peak wavelength was obtained. In addition, FIG. 10 shows an emission spectrum of the phosphors of Examples 15 to 19 when excited with an excitation wavelength of 400 nm, FIG. 11 shows a reflection spectrum, and FIG. 12 shows an excitation spectrum.

(Examples 20 to 24)
Further, in the carbonitride phosphors of Examples 20 to 24, the composition formula is represented by Sr _1−z Y _{1 + z} Si ₄ (C, N) ₇ : Eu, and the value of z, that is, Sr and Y is configured. This was manufactured in the same manner as in Example 1 except that the molar ratio of each Sr amount and Y amount was adjusted so as to have the distribution shown in Table 7. The light emission characteristics in each example are shown in Table 8.

  Good emission characteristics were obtained when the molar ratio of Sr / Y charged in the phosphor ranged from 0.45 to 3.5. In particular, as shown in Table 8, when the Sr / Y charge molar ratio is in the range of 0.95 to 2.9, the relative luminance increases by 22.5 to 30.2 percent compared to the comparative example. Suitable luminescent characteristics were obtained. In addition, FIG. 13 shows an emission spectrum of the phosphors of Examples 20 to 24 when excited with an excitation wavelength of 400 nm, FIG. 14 shows a reflection spectrum, and FIG. 15 shows an excitation spectrum. In Tables 1 to 7, Examples 1 and 5, 10, 15, and 22 are carbonitride phosphors having the same composition. In addition, analysis of the amount of C (weight%) in the elemental analysis results in the table is performed by burning carbon in the sample by a high frequency induction heating furnace method using a carbon sulfur analyzer (EMIA-320V) manufactured by Horiba, Ltd. Measured. Further, the amounts of O and N were measured with an oxygen / nitrogen analyzer (EMGA-650) manufactured by Horiba. The emission characteristics in the table are those when excited at a wavelength of 400 nm.

  From the above results, the carbonitride phosphor according to the present invention is excited by light from an excitation light source having an emission peak wavelength in the range of 240 nm to 450 nm, and emits fluorescence having a peak wavelength in the wavelength range of 450 to 650 nm. To do. Moreover, it was confirmed that the average particle diameter of the phosphor is 2 μm or more and 20 μm or less.

  Moreover, the phosphor of the present invention is a carbonitride phosphor containing an alkaline earth metal and a rare earth in its composition, and has high emission luminance in a wide temperature range. Furthermore, it has the feature that the decrease in light emission luminance at high temperatures can be minimized. In particular, the carbon content in the carbonitride phosphor is 0.5 wt% or more and 5 wt% or less, preferably 2 wt% or more and 4 wt% or less, and / or the molar ratio of the alkaline earth metal to the rare earth is 0.9. To 1.0, preferably 0.93 to 0.96, or / and the molar ratio of carbon to nitrogen is 0.19 to 0.25, preferably 0.20 to 0.245. Compared to the carbonitride phosphor of the comparative example which does not include an earth metal and contains only rare earth, an improvement of equivalent to 13.8% at 100 ° C. and an equivalent to 22.2% at 200 ° C. are seen. (Table 5). That is, by specifying the carbon content or the alkaline earth metal content within the above range, it is possible to improve light-emitting characteristics such as weather resistance and life characteristics at room temperature to high temperature. As a result, in the light emitting device equipped with the carbonitride-based phosphor of the present invention, even if the carbonitride-based phosphor is placed very close to the heat source, the emitted light with stable brightness and chromaticity values can be obtained. The light emitting device can be released and has excellent light emitting characteristics and durability.

(Light emitting device)
Next, a light emitting device using the carbonitride phosphor as a wavelength conversion member will be described. Examples of the light emitting device include a lighting device such as a fluorescent lamp and a display device such as a display and a radar. A semiconductor light emitting element is used as an excitation light source for the wavelength conversion member. Here, the light emitting element is used to include not only an element that emits visible light but also an element that emits near ultraviolet light, far ultraviolet light, or the like. In addition to the semiconductor light emitting element, an excitation light source having an emission peak wavelength in the short wavelength region from ultraviolet to visible light, such as a mercury lamp used in an existing fluorescent lamp, can be appropriately used as the excitation light source.

(Embodiment 1)
Here, as a first embodiment of the light emitting device, a bullet type semiconductor light emitting device including a light emitting element that emits light in a short wavelength region from near ultraviolet to visible light is used as an excitation light source. The light emitting element is small in size, has high power efficiency, and emits bright colors. In addition, since the light emitting element is a semiconductor element, there is no fear of a broken ball. In addition, it has excellent initial drivability and is strong against vibration and repeated on / off lighting. Therefore, a light-emitting device that combines a light-emitting element and a carbonitride-based phosphor is preferable.

  FIG. 20 shows a bullet-type light emitting device 1 according to Embodiment 1 of the present invention. The light-emitting device 1 is in a concave cup 10 formed by a lead frame 4 made of a conductive member. The light-emitting device 2 is placed on the lead frame 4 and is emitted from the light-emitting element 2. A phosphor 3 that converts the wavelength of at least a part of the emitted light. As the light emitting element 2, a light emitting element having an emission peak wavelength at about 360 nm to 480 nm is used. Positive and negative electrodes 9 formed on the light emitting element 2 are electrically connected to the lead frame 4 via conductive bonding wires 5. Further, the light emitting element 2, the lead frame 4, and the bonding wire 5 are covered with a shell-shaped mold 11 so that the lead frame electrode 4 a which is a part of the lead frame 4 protrudes. The mold 11 is filled with a light-transmitting resin 6, and the resin 6 contains a phosphor 3 that is a wavelength conversion member. The resin 6 is preferably a silicone resin composition, but an insulating resin composition having translucency such as an epoxy resin composition and an acrylic resin composition can also be used. By supplying electric power from an external power source to the lead frame electrode 4 a protruding from the resin 6, light is emitted from the light emitting layer 8 contained in the layer of the light emitting element 2. The emission peak wavelength output from the light emitting layer 8 has an emission spectrum near 500 nm or less in the ultraviolet to blue region. Part of the emitted light excites the phosphor 3, and light having a wavelength different from the wavelength of the main light source from the light emitting layer 8 is obtained.

  The phosphor 3 is preferably mixed in the resin at a substantially uniform ratio. Thereby, light without color unevenness is obtained. The luminance and wavelength of the light emitted from the light emitting device 1 are determined by the particle size of the phosphor 3 sealed in the light emitting device 1, the uniformity after coating, the thickness of the resin containing the phosphor, and the like. to be influenced. Specifically, if the amount and size of the phosphor that is excited before the light emitted from the light emitting element 2 is emitted to the outside of the light emitting device 1 is unevenly distributed at the site in the light emitting device 1, Color unevenness occurs. Further, in the phosphor powder, light emission is considered to occur mainly on the particle surface. Therefore, if the average particle size is generally small, a surface area per unit weight of the powder can be secured and a reduction in luminance can be avoided. Further, the small-sized phosphor can diffuse and reflect light to prevent uneven color of the emitted color. On the other hand, the large particle size phosphor improves the light conversion efficiency. Therefore, it becomes possible to extract light efficiently by controlling the amount and particle size of the phosphor.

  Further, it is more desirable that the phosphor disposed in the light emitting device 1 is resistant to heat generated from the light source and weather resistant that is not affected by the use environment. This is because the fluorescence intensity generally decreases as the temperature of the medium increases. This is because as the temperature rises, intermolecular collision increases and potential energy loss is caused by non-radiative transition deactivation.

  However, the phosphor 3 can be blended so as to be partially distributed in the resin. As an example, the phosphor 3 according to Embodiment 1 is extremely excellent in heat resistance as described above, and can be placed very close to the light emitting element 2. Thereby, the wavelength of the light from the light emitting element 2 can be efficiently converted, and a light emitting device having excellent light emission efficiency can be obtained.

  Further, two or more kinds of phosphors may be contained in the resin 6. Thereby, the wavelength of the main light source output from the light emitting layer can be converted by the first phosphor, and light that has been wavelength-converted by the second phosphor can be obtained. By adjusting the combination of the plurality of phosphors, the main light source, the light wavelength-converted by the first phosphor, the light wavelength-converted by the second phosphor, and the main light source directly the second fluorescence Various colors can be expressed by combining light that has been wavelength-converted by the body. At this time, by disposing the heat-resistant phosphor according to the first embodiment in the vicinity of the heat source, it is possible to significantly reduce the deterioration of the light emitting device and extend the lifetime.

(Light emitting element)
The light-emitting element can emit light from the ultraviolet region to the visible light region. In particular, it is preferable to use a light emitting element having an emission peak wavelength in the vicinity of 350 nm to 550 nm and to have a light emitting layer capable of emitting light having an emission wavelength capable of efficiently exciting a fluorescent substance. Here, a nitride semiconductor light emitting element will be described as an example of the light emitting element, but the present invention is not limited to this.

  Specifically, the light emitting element is preferably a nitride semiconductor element containing In or Ga. This is because the carbonitride-based phosphor according to Example 1 emits light strongly in the vicinity of 280 nm to 400 nm, and thus a light emitting element in the wavelength range is required. The light emitting element emits light having an emission peak wavelength in the short wavelength region from near ultraviolet to visible light, and at least one or more phosphors are excited by the light from the light emitting element to exhibit a predetermined emission color. In addition, since the light-emitting element can narrow the emission spectrum width, it can excite the carbonitride phosphor efficiently, and the light-emitting device can substantially affect the color tone change. It is also possible to emit an emission spectrum without any.

  Thus, by using the light emitted from the light emitting element as an excitation light source, an efficient light emitting device with low power consumption compared to a conventional mercury lamp can be realized. The light-emitting device according to Embodiment 1 can use the carbonitride-based phosphor described above.

(Embodiment 2)
Next, a light emitting device 20 according to Embodiment 2 of the present invention is shown in FIG. In this light emitting device 20, the same members as those in the light emitting device 1 according to Embodiment 1 are denoted by the same reference numerals, and the description thereof is omitted. In the light emitting device 20, the resin 6 containing the phosphor 3 is filled only in the concave cup 10 molded by the lead frame 4. The phosphor 3 is not contained in the resin 6 filled inside the mold 11 and outside the cup 10. The resin containing phosphor 3 and the resin not containing are preferably the same, but they may be different. In the case of different types of resins, the softness can be changed using the difference in temperature required for each resin to cure.

  In the light emitting device 20, since the light emitting element 2 is placed at substantially the center of the bottom surface forming the opening in the cup 10, the light emitting element 2 is embedded in the resin 6 including the phosphor 3. In order for the light from the light emitting layer 8 to be wavelength-converted by the phosphor 3 without unevenness, the light from the light emitting element has only to pass through the phosphor-containing resin uniformly. That is, the phosphor-containing resin film through which light from the light emitting layer 8 passes may be made uniform. Therefore, the size of the cup 10 and the mounting position of the light emitting element 2 may be determined so that the distance from the periphery of the light emitting element 2 to the wall surface and upper part of the cup 10 is uniform. With this light emitting device 20, it becomes easy to uniformly adjust the film thickness of the resin 6 containing the phosphor 3.

  Further, similarly to the first embodiment, the phosphor 3 can be blended so as to be partially unevenly distributed in the resin. As an example, the light emitting device 50 shown in FIG. 22 is formed by forming a phosphor layer having a substantially uniform thickness in the vicinity of the periphery of the light emitting element 2. As a result, the amount of phosphor through which light emitted from the light emitting element 2 passes is substantially constant, that is, since the same amount of phosphor is wavelength-converted, the light emitting device with reduced color unevenness and it can.

(Embodiment 3)
Furthermore, as a light emitting device according to Embodiment 3 of the present invention, a cap type light emitting device 30 is shown in FIG. As the light emitting element 2, a light emitting element having an emission peak wavelength at about 400 nm is used. The light emitting device 30 is configured by covering a cap 31 made of a light transmissive resin in which the phosphor 3 is dispersed on the surface of the mold 11 of the light emitting device 20 of the second embodiment.

  The cap 31 has the phosphor 3a uniformly dispersed in the light transmissive resin 6a. The resin 6 a containing the phosphor 3 a is molded into a shape that fits into the shape of the outer surface of the mold 11 of the light emitting device 30. Alternatively, a manufacturing method is also possible in which a light-transmitting resin 6a containing a predetermined in-frame phosphor is put, and then the light emitting device 30 is pushed into the mold and molded. As a specific material of the resin 6a of the cap 31, a transparent resin, silica gel, glass, an inorganic binder, etc. excellent in temperature characteristics and weather resistance such as an epoxy resin, a urea resin, and a silicone resin are used. In addition to the above, thermosetting resins such as melamine resins and phenol resins can be used. In addition, thermoplastic resins such as polyethylene, polypropylene, polyvinyl chloride, and polystyrene, thermoplastic rubbers such as styrene-butadiene block copolymer, segmented polyurethane, and the like can also be used. Further, a diffusing agent, barium titanate, titanium oxide, aluminum oxide or the like may be contained together with the phosphor. Moreover, you may contain a light stabilizer and a coloring agent. The phosphor 3a used for the cap 31 can be not only one type but also a mixture of a plurality of phosphors or a layered structure.

  In the light emitting device 30, the phosphor 3 a can be contained only in the resin 6 a in the cap 31, but in addition to this, the cup 6 may be filled with the resin 6 containing the phosphor 3. The types of the phosphors 3 and 3a may be the same or different, and each of the resins 6 and 6a may have a plurality of phosphors. As a result, various emission colors can be realized. An example is a light emitting device that emits white light. The light emitted from the light emitting element 2 excites the phosphor 3 and emits light from blue green to green and from yellow to red. A part of the light emitted from the phosphor 3 excites the phosphor 3a of the cap 31, and emits light from green to a yellow region. Due to the mixed color light of these phosphors, white light is emitted from the surface of the cap 31 to the outside. Further, the above-described heat-resistant carbonitride-based phosphor is contained in the cup 10, and another type of phosphor 3a is used in the cap 31 where the phosphor is not directly affected by the heat generated from the light emitting element 2. Thus, a light emitting device with a long lifetime can be obtained. In addition, the carbonitride-based phosphor described above can be placed very close to the heat source, as in the first and second embodiments.

(Embodiment 4)
Furthermore, FIG. 24 shows a surface mount type light emitting device 100 as the light emitting device according to the fourth embodiment of the present invention. FIG. 24A is a plan view, and FIG. 24B is a cross-sectional view. As the light-emitting element 101, an ultraviolet-excited nitride semiconductor light-emitting element can be used. The light-emitting element 101 may be a blue-excited nitride semiconductor light-emitting element. Here, the light emitting element 101 excited by ultraviolet light will be described as an example. The light emitting element 101 uses a nitride semiconductor light emitting element having an InGaN semiconductor with an emission peak wavelength of about 370 nm as a light emitting layer. The light-emitting element 101 includes a p-type semiconductor layer and an n-type semiconductor layer (not shown), and the p-type semiconductor layer and the n-type semiconductor layer have a conductive wire 104 connected to the lead electrode 102. Is formed. An insulating sealing material 103 is formed so as to cover the outer periphery of the lead electrode 102 to prevent a short circuit. A light-transmitting window 107 extending from a Kovar lid 106 at the top of the package 105 is provided above the light emitting element 101. On the inner surface of the translucent window 107, a uniform mixture of the phosphors 3, 3a and the coating member 109 is applied to almost the entire surface.

  Next, each electrode of the die-bonded light emitting element 101 and each lead electrode 102 exposed from the bottom of the package recess are electrically connected by a conductive wire 104 such as an Ag wire. After sufficiently removing moisture in the recess of the package, sealing is performed with a Kovar lid 106 having a glass window 107 at the center, and seam welding is performed. The glass window portion contains carbonitride-based phosphors 3 and 3a, which are wavelength conversion members, with respect to a slurry composed of 90% by weight of nitrocellulose and 10% by weight of γ-alumina in advance. The color conversion member is configured by applying the film to the back surface of the film and curing it by heating at 220 ° C. for 30 minutes. The light output from the light-emitting element 101 of the light-emitting device 100 thus formed excites the phosphors 3 and 3a, and a light-emitting device capable of emitting a desired color with high luminance can be obtained. This makes it possible to obtain a light emitting device with extremely simple chromaticity adjustment and excellent mass productivity and reliability.

  In Embodiment 4, the light in the ultraviolet region used as the excitation light source belongs to a portion having low visibility, and the light emission color of the light emitting device is substantially determined by the light emission color of the fluorescent material used. Further, even when a color shift of a light emitting element due to a change in input current or the like occurs, a color shift of a fluorescent material that emits light in the visible light region can be suppressed to be extremely small. As a result, a light emitting device with little color tone change is provided. Can do. Although the ultraviolet region generally has a wavelength shorter than 380 nm or 400 nm, light having a wavelength of 420 nm or less is hardly visible in terms of visibility, so that the color tone is not greatly affected.

  In addition, the carbonitride-based phosphor described above can be placed very close to the heat source, as in the first and second embodiments.

(Embodiment 5)
FIG. 25A shows a perspective view of a semiconductor light emitting device 40 according to Embodiment 5 of the present invention. FIG. 25B is a cross-sectional view taken along the line II-II ′ of the semiconductor light emitting device 40 shown in FIG. The outline of the semiconductor light emitting device 40 of the fifth embodiment will be described below with reference to FIGS. 25 (a) and 25 (b). The semiconductor light emitting device 40 is configured such that a package 12 having a space that opens in a substantially concave shape toward the top is mounted on the lead frame 4. Further, a plurality of light emitting elements 2 are mounted on the exposed lead frame 4 in the space of the package 12. That is, the package 12 is a frame that surrounds the light emitting element 2. In addition, a protective element 13 such as a Zener diode, which is energized when a voltage higher than a specified voltage is applied, is also placed in the open space of the package 12. Further, the light emitting element 2 is electrically connected to the lead frame 4 via bonding wires 5 and bumps. In addition, the open space of the package 12 is filled with the sealing resin 6.

  The phosphor 3 contained in the package 12 is shown in FIG. 25B (the phosphor 3 in FIG. 25A is omitted). As the phosphor 3, the above-described carbonitride-based phosphor can be used, and the phosphor content in the resin 6 is the same as in the first to fourth embodiments.

  If the carbonitride phosphor described above is used in the light emitting devices according to Examples 1 to 5, the phosphor layer can be uniformly and thinly formed in the vicinity of the light source of the light emitter. Therefore, the use efficiency of materials and processes is increased by forming the phosphor layer only in necessary portions. In addition, it is highly productive and can handle many types of phosphors in the same process. The phosphor layer is preferably thinly coated with particles uniformly. This is because if the phosphor layer is too thick, the phosphor crystals overlap and cause shadowing, which reduces efficiency.

  The carbonitride-based phosphor of the present invention, a light-emitting device using the same, and a method for producing the carbonitride-based phosphor include fluorescent display tubes, displays, PDPs, CRTs, FLs, FEDs, projection tubes, etc., particularly blue light-emitting diodes Alternatively, it can be suitably used for a white illumination light source, an LED display, a backlight light source, a traffic light, an illumination switch, various sensors, various indicators, and the like that are extremely excellent in light emission characteristics using an ultraviolet light emitting diode as a light source.

It is a graph of the emission spectrum when the fluorescent substance which concerns on Examples 1-4 is excited at 400 nm. It is a graph of the reflection spectrum of the fluorescent substance which concerns on Examples 1-4. It is a graph of the excitation spectrum of the fluorescent substance which concerns on Examples 1-4. It is a graph of the emission spectrum when the fluorescent substance which concerns on Examples 5-8 is excited at 400 nm. It is a graph of the reflection spectrum of the fluorescent substance which concerns on Examples 5-8. It is a graph of the excitation spectrum of the fluorescent substance which concerns on Examples 5-8. It is a graph of the emission spectrum when the fluorescent substance which concerns on Examples 9-14 is excited at 400 nm. It is a graph of the reflection spectrum of the fluorescent substance which concerns on Examples 9-14. It is a graph of the excitation spectrum of the fluorescent substance which concerns on Examples 9-14. It is a graph of the emission spectrum when the fluorescent substance which concerns on Examples 15-19 is excited at 400 nm. It is a graph of the reflection spectrum of the fluorescent substance which concerns on Examples 15-19. It is a graph of the excitation spectrum of the fluorescent substance which concerns on Examples 15-19. It is a graph of the emission spectrum when the phosphor according to Examples 20 to 24 is excited at 400 nm. It is a graph of the reflection spectrum of the fluorescent substance which concerns on Examples 20-24. It is a graph of the excitation spectrum of the fluorescent substance which concerns on Examples 20-24. FIG. 16A is a 1000 × magnified photograph of the phosphor of Comparative Example 1, and FIG. 16B shows a 5000 × magnified photograph thereof. It is an X-ray diffraction diagram of Examples 1-4. It is an X-ray diffraction diagram of Examples 5 and 6. 6 is an X-ray diffraction diagram of Examples 7 and 8. FIG. It is sectional drawing which shows the bullet-type light-emitting device concerning Embodiment 1 of this invention. It is sectional drawing which shows the bullet-type light-emitting device concerning Embodiment 2 of this invention. It is sectional drawing which shows the modification of the bullet-type light-emitting device which concerns on Embodiment 2 of this invention. It is sectional drawing which shows the bullet-type light-emitting device concerning Embodiment 3 of this invention. FIG. 24A is a plan view showing a surface-mounted light emitting device according to Embodiment 4 of the present invention, and FIG. 24B is a cross-sectional view showing the light emitting device of FIG. FIG. 25A is a plan view showing a surface-mounted light emitting device according to Embodiment 5 of the present invention, and FIG. 25B is a cross-sectional view taken along the line II-II ′ of the light emitting device of FIG. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 20, 30, 40, 50, 100 ... Light-emitting device 2 ... Light emitting element 3 ... Phosphor 3a ... Small particle fluorescent substance 4 ... Lead frame 4a ... Lead frame electrode 5 ... Bonding wire 6 ... Resin 6a ... Resin 8 ... Light emission Layer 9 ... Electrode 10 ... Cup 11 ... Mold 12 ... Package 13 ... Protection element 31 ... Cap 101 ... Light emitting element 102 ... Lead electrode 103 ... Insulating sealing material 104 ... Conductive wire 105 ... Package 106 ... Kovar lid 107 ... Transparent Optical window (glass window)
109 ... Coating member

Claims (10)

A carbonitride-based phosphor activated by europium that emits yellow to green light by absorbing near ultraviolet rays, and is represented by the following general formula, and u, v, w, x, y, and z are as follows: A carbonitride phosphor characterized by having a range of
A _u B _v Si _w C _x N _y O _z : Eu ²⁺
A is Sr or Ba,
B is Y or Lu;
Si is silicon, C is carbon, N is nitrogen, O is oxygen, and Eu is europium.
1 ≦ u + v ≦ 3, 0.5 ≦ u ≦ 1.5, 0.5 ≦ v ≦ 1.5, 2 ≦ w ≦ 6, 0.01 ≦ x ≦ 8, 0.05 ≦ y ≦ 8, 0. 01 ≦ z ≦ 8 The carbonitride phosphor according to claim 1, wherein the composition formula is SrYSi ₄ (C, N, O) _7-δ : Eu or SrLuSi ₄ (C, N, O) _7-δ : Eu. A carbonitride-based phosphor characterized by that. A carbonitride-based phosphor activated with europium that absorbs near ultraviolet rays and emits yellow to green light, and is represented by the following general formula: t, u, v, w, x, y, z Is a carbonitride phosphor characterized by having the following range.
_{A u B v Si w Al t} C x N y O z: Eu 2+
A is Sr or Ba,
B is Y or Lu;
Si is silicon, Al is aluminum, C is carbon, N is nitrogen, O is oxygen, and Eu is europium.
1 ≦ u + v ≦ 3, w + t = 4, 0.5 ≦ u ≦ 1.5, 0.5 ≦ v ≦ 1.5, 3.90 ≦ w ≦ 3.99, 0.01 ≦ x ≦ 7, 05 ≦ y ≦ 7, 0.01 ≦ z ≦ 7, 0.01 ≦ t ≦ 0.1 The carbonitride-based phosphor according to any one of claims 1 to 3,
A carbonitride phosphor characterized by having an A / B molar ratio of 0.45 to 3.0.   5. The carbonitride-based phosphor according to claim 1, wherein oxygen is contained in the composition in an amount of 0.5 wt% to 5 wt%. A carbonitride-based phosphor according to any one of claims 1 to 5,
A carbonitride phosphor having a C / N molar ratio of 0.05 to 0.30.   The carbonitride phosphor according to any one of claims 1 to 6, wherein carbon is contained in an amount of 0.5 wt% to 5 wt%.   The carbonitride-based phosphor according to any one of claims 1 to 7, wherein the phosphor has an average particle size of 2 µm or more and 20 µm or less. An excitation light source having a first emission spectrum that emits near ultraviolet light;
One or two or more wavelength conversion members that absorb at least part of the first emission spectrum and emit the second emission spectrum,
The light emitting device, wherein the wavelength conversion member includes the carbonitride-based phosphor according to any one of claims 1 to 8. A method for producing a carbonitride-based phosphor activated with europium represented by the following general formula:
A step of measuring and mixing each raw material containing an alkaline earth metal element, a rare earth element, europium, carbon, silicon, and nitrogen so that the molar ratio of C / N is 0.05 to 0.30;
Firing the mixed raw materials and further reducing;
A method for producing a carbonitride-based phosphor, comprising:
A _u B _v Si _w C _x N _y O _z : Eu ²⁺
A is Sr or Ba,
B is Y or Lu;
Si is silicon, C is carbon, N is nitrogen, O is oxygen, and Eu is europium.
1 ≦ u + v ≦ 3, 0.5 ≦ u ≦ 1.5, 0.5 ≦ v ≦ 1.5, 2 ≦ w ≦ 6, 0.01 ≦ x ≦ 8, 0.05 ≦ y ≦ 8, 0. 01 ≦ z ≦ 8