KR20190038733A - Barium-yttrium-orthosilicate fluorescent material for white LED - Google Patents

Abstract

Disclosed is a phosphor which emits emission light having a wide wavelength band. A parent of the phosphor has a trigonal structure and comprises barium-yttrium-orthosilicate represented by composition formula Ba_(9-x)M_xY_2Si_6O_24. In the composition formula, M is at least one selected from the group consisting of Bi, Eu, Ce, Mn, Tb, and Na, and x is more than or equal to 0.0015 and less than or equal to 1.85.

Description

Barium-yttrium-orthosilicate fluorescent material for white LEDs {Barium-yttrium-orthosilicate fluorescent material for white LED}

An embodiment according to the concept of the present invention relates to a barium-yttrium-orthosilicate phosphor for a white LED, and more particularly to a phosphor for a white LED in which light emission characteristics are improved by emitting light in a broader wavelength band.

[0002] Phosphors for wavelength conversion are substances that convert wavelength bands of various light sources into specific wavelength bands, and their importance in the lighting industry is gradually increasing. Particularly, when a light emitting diode (LED) is used as a light source, phosphors are crucial elements for manufacturing a white light emitting device and improving the performance thereof, and thus technologies for phosphors have been appreciated as a core technology.

There are three main types of manufacturing methods for white LEDs. The first is the multi-chip method that combines the red, blue, and green LEDs according to the classic RGB concept. This method is disadvantageous in that the deterioration rate of the LED chip is different according to each light emitting wavelength band, so that discoloration frequently occurs and it is also vulnerable to a change in the light emitting wavelength depending on the temperature. The second is a method of manufacturing a white LED device by applying a yellow-green phosphor on a blue LED chip. The white LED obtained by this method has an advantage of high brightness, but it has a disadvantage that it is not easy to control the color and is free from the color conversion phenomenon according to the temperature change. It is also a problem that it is difficult to mass-produce white LDEs having the same color coordinates because of the difference in wavelength between blue and yellow. In recent years, attempts have been made to solve the above-mentioned problems by further adding a red phosphor, but it is difficult to ensure a sufficient CRI when each half-width of each phosphor is low, and the implementation of white light is still limited.

Finally, the third is a method of obtaining white light by applying multiple red, green, and blue phosphors on the excitation light source in the ultraviolet and near ultraviolet regions in a relatively recently established manner. And has a high color rendering index in that it emits light similar to the light distribution of sunlight.

LEDs using ultraviolet to near ultraviolet excitation light sources are attracting attention as a method of realizing a light source close to sunlight. However, when the near ultraviolet light is used as the excitation light source, the efficiency of light emission is not good and there is a disadvantage that the production cost is increased due to multiple application of the phosphor. Moreover, since the wavelength band of the excitation light is limited, it is difficult to efficiently realize white light.

Korean Patent No. 10-1258229

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above problems, and it is an object of the present invention to provide a barium-yttrium-orthosilicate phosphor for a white LED which emits broad wavelength band emission light even if the wavelength band of the excitation light is limited.

A second object of the present invention is to realize white light efficiently with only a single phosphor.

In order to achieve the above object, the phosphor of the present invention comprises a barium-yttrium-orthosilicate having a trigonal structure and expressed by the composition formula Ba _9-x M _x Y ₂ Si ₆ O ₂₄ , In the above composition formula, M is at least one selected from the group consisting of Bi, Eu, Ce, Mn, Tb and Na, and 0.0015? X? 1.85.

Wherein M includes at least two elements selected from the group, and the two or more elements satisfy the condition that 0.0015? X? 1.85.

Ba (Ⅱ), 9-coordinated Ba (Ⅱ) and 10-coordinated Ba (Ⅱ) are all included in the matrix.

Further, the phosphor satisfies the following formula (1).

≪ Formula 1 >

Ba _{9-3 (m + n) / 2} Bi _m Eu _n Y ₂ Si ₆ O ₂₄

Provided that 0.001? M? 0.1 and 0? N? 0.1, and the excitation wavelength is 330 nm or more and 380 nm or less.

The phosphor preferably satisfies the following formula (2).

(2)

Ba _{9-3 (m / 2) -n-3 (p / 2)} Ce _m Mn _n Tb _p Y ₂ Si ₆ O ₂₄

Wherein 0.005? M? 0.4, 0? N? 0.5 and 0? P? 0.5, and the excitation wavelength is 270 nm or more and 360 nm or less.

Further, the phosphor satisfies the following formula (3).

(3)

Ba _{9- (1 / 2p) -q} Na _p M _q Y ₂ Si ₆ O ₂₄

In the above formula 3, M is at least one selected from the group consisting of Bi, Eu, Ce, Mn, Tb and Na, satisfies the condition of 0? P? 0.8 and 0.0015? Q? 1.05, Is not less than 250 nm and not more than 470 nm.

The phosphor preferably satisfies the following formula (4).

≪ Formula 4 >

Ba _{8.9 - (1 / 2p) -q} Na _p Eu _0.1 Mn _q Y ₂ Si ₆ O ₂₄

However, the condition of 0? P? 0.8 and 0? Q? 0.8 is satisfied.

In order to achieve the second object, the phosphor of the present invention comprises a barium-yttrium-orthosilicate having a trigonal structure and expressed by a composition formula Ba ₉ M _y Y _{2 -y} Si ₆ O ₂₄ , In the composition formula, M is at least one species selected from the group consisting of Bi and Eu, and 0.001? Y? 0.2.

Ba (Ⅱ), 9-coordinated Ba (Ⅱ) and 10-coordinated Ba (Ⅱ) are all included in the matrix.

Further, the phosphor satisfies the following formula (5).

≪ Formula 5 >

Ba ₉ Y _{2 -mn} Bi _m Eu _n Si ₆ O ₂₄ wherein 0.001 ≤ m ≤ 0.1 and 0 ≤ n ≤ 0.1, and the excitation wavelength is 330 nm or more and 380 nm or less.

The barium-yttrium-orthosilicate phosphor for a white LED of the present invention as described above can efficiently convert light of a wavelength ranging from about mid 300 nm to less than mid-700 nm even when ultraviolet light or near ultraviolet light is used as an excitation light source, And it is possible to provide an effect of improving the wavelength band and the light emission intensity.

In addition, the phosphor that can be obtained when Bi (III) and Eu (III) are substituted with barium or yttrium at an appropriate ratio in the matrix can provide an effect of efficiently emitting white light even with a single phosphor alone.

Further, the phosphors that can be obtained when Ce (III), Mn (II), and Tb (III) are substituted with barium in an appropriate ratio to the matrix can realize red, blue, and green light respectively or simultaneously It is possible to provide an effect of improving the luminescence characteristics. In particular, when red, blue, and green light are simultaneously realized, an effect that white light is efficiently emitted by a single phosphor alone can be provided.

In addition, the phosphor that can be obtained when Eu (III) and Na (I) are substituted with barium in an appropriate ratio to the mother body can provide an effect of efficiently emitting white light even with only yellow light or a single phosphor.

)의 변화에 대한 도시이다.
도 6는 발명의 실시예에 따른 모체에 Ce(Ⅲ), Mn(Ⅱ), Tb(Ⅲ)를 각각 치환한 형광체의 여기광의 파장대역과 방출광의 파장대역 및 강도에 대한 도시이다.
도 7는 발명의 실시예에 따른 모체에 Ce(Ⅲ), Mn(Ⅱ), Tb(Ⅲ)를 치환한 형광체의 여기광의 파장대역과 방출광의 파장대역 및 강도에 대한 도시이다.
도 8은 발명의 실시예에 따른 모체에 Ce(Ⅲ), Mn(Ⅱ), Tb(Ⅲ)를 치환한 형광체의 에너지 전달 효율(

)의 변화에 대한 도시이다.
도 9는 발명의 실시예에 따른 모체에 Ce(Ⅲ), Mn(Ⅱ), Tb(Ⅲ)를 치환한 형광체의 CIE 색도분포에 대한 도시이다.
도 10는 발명의 실시예에 따른 모체에 Na(Ⅰ), Eu(Ⅲ)을 치환한 형광체의 여기광의 파장대역과 방출광의 파장대역 및 강도에 대한 도시이다.
도 11는 발명의 실시예에 따른 모체에 Na(Ⅰ)의 치환비율에 따른 방출광의 개형 변화에 대한 도시이다.
도 12은 발명의 실시예에 따른 모체에 Na(Ⅰ), Eu(Ⅲ), Mn(Ⅱ)을 치환한 형광체의 여기광의 파장대역과 방출광의 파장대역 및 강도에 대한 도시이다.
도 13은 발명의 실시예에 따른 모체에 Na(Ⅰ), Eu(Ⅲ), Mn(Ⅱ)을 치환한 형광체의 Mn(Ⅱ) 치환비율 변화에 따른 방출광의 개형 변화에 대한 도시이다.
도 14는 발명의 실시예에 따른 모체에 Na(Ⅰ), Eu(Ⅲ), Mn(Ⅱ)을 치환한 형광체의 에너지 전달 효율(

)의 변화에 대한 도시이다.
도 15은 발명의 실시예에 따른 모체에 Na(Ⅰ), Eu(Ⅲ), Mn(Ⅱ)을 치환한 형광체의 연색지수(CRI) 및 색온도(CCT)에 대한 도시이다.1 is a structural view showing a three-dimensional structure of a matrix according to an embodiment of the present invention.
2 is a diagram showing the wavelength band of the excitation light, the wavelength band of the emitted light, and the intensity of the fluorescent material in which Bi (III) is substituted for the matrix according to the embodiment of the present invention.
FIG. 3 is a diagram showing the wavelength band of the excitation light and the wavelength band and intensity of the emitted light of the phosphor in which Bi (III) and Eu (III) are substituted for the matrix according to the embodiment of the present invention.
Fig. 4 is a diagram showing the CIE chromaticity distribution of phosphors in which Bi (III) and Eu (III) are substituted for a matrix according to an embodiment of the present invention.
Fig. 5 is a graph showing the energy transfer efficiency (Fig. 5) of a phosphor substituted by Bi (III) and Eu (III)

). ≪ / RTI >
FIG. 6 is a diagram showing the wavelength band of the excitation light and the wavelength band and intensity of the emitted light of the phosphor in which Ce (III), Mn (II) and Tb (III) are substituted respectively in the matrix according to the embodiment of the present invention.
FIG. 7 is a diagram showing the wavelength band of the excitation light and the wavelength band and intensity of the emitted light of the phosphor in which Ce (III), Mn (II) and Tb (III) are substituted for the matrix according to the embodiment of the present invention.
FIG. 8 is a graph showing the energy transfer efficiencies of phosphors substituted with Ce (III), Mn (II) and Tb (III)

). ≪ / RTI >
FIG. 9 is a diagram showing CIE chromaticity distributions of phosphors in which Ce (III), Mn (II), and Tb (III) are substituted for a matrix according to an embodiment of the present invention.
FIG. 10 is a diagram showing the wavelength band of the excitation light and the wavelength band and intensity of the emitted light of the phosphor in which Na (I) and Eu (III) are substituted for the matrix according to the embodiment of the present invention.
FIG. 11 is a diagram showing an open-type change of emitted light according to the substitution ratio of Na (I) to a matrix according to an embodiment of the present invention.
FIG. 12 is a diagram showing wavelength bands of excitation light and wavelength band and intensity of emitted light of phosphors in which Na (I), Eu (III) and Mn (II) are substituted for the matrix according to the embodiment of the present invention.
FIG. 13 is a diagram showing a change in the emission profile of the emitted light according to the Mn (II) substitution ratio of a phosphor substituted with Na (I), Eu (III), and Mn (II) in a mother according to an embodiment of the present invention.
Fig. 14 is a graph showing the energy transfer efficiencies of phosphors substituted with Na (I), Eu (III), and Mn (II)

). ≪ / RTI >
FIG. 15 is a graph showing the CRI and the color temperature (CCT) of a phosphor in which Na (I), Eu (III) and Mn (II) are substituted for the matrix according to the embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

However, the embodiments of the present invention can be modified into various other forms, and the scope of the present invention is not limited to the embodiments described below. Embodiments of the present invention are also provided to more fully describe the present invention to those skilled in the art. Therefore, the shapes and sizes of the elements constituting the drawings and the like can be exaggerated for clarity.

The present invention the matrix that has a trigonal crystal system (Trigonal) structure, composition formula Ba _9-x M _x Y ₂ Ba, which is represented by Si ₆ O _{24-yttrium-comprises} a ortho silicate, in the formula M is Bi, Eu, Ce , Mn, Tb, and Na, and 0.0015? X? 1.85.

According to an embodiment, M includes at least two elements selected from the group consisting of Bi, Eu, Ce, Mn, Tb, and Na, and both of the two or more elements satisfy the condition that 0.0015? X? have.

Matrix of the present invention has a trigonal crystal system (Trigonal) crystal structure, a composition formula of the matrix is Ba ₉ Y ₂ Si ₆ O ₂₄ is a single phase. The host of the present invention includes Ba (II) having three kinds of coordination bonds, and preferably has a three-system crystal structure.

1 is a structural view showing a three-dimensional structure of a matrix according to an embodiment of the present invention. Referring to FIG. 1, Ba (1) is Ba (II) in which oxygen is 12 coordinated, Ba (2) in FIG. 1 means Ba , Ba (3) represents Ba (II) in which oxygen is coordinated to 10 carbon atoms.

In FIG. 1, YO ₆ has an octahedral structure and SiO _{4 -} has a tetrahedral structure. The phosphors according to an embodiment of the present invention can be obtained by adding one or more kinds of activators and sensitizers based on the crystal structure of the host.

It is particularly important that the matrix contains both Ba (II) in which the oxygen is coordinated to 12, Ba (II) in the 9-coordinate coordination, and Ba (II) in the 10 coordination. As will be described with reference to Fig. 11, the crystal field effect experienced by metal ions substituted with Ba (1), metal ions substituted with Ba (2), and metal ions substituted with Ba (3) are different. Since arbitrary metal ions can be substituted for Ba (1), Ba (2), and Ba (3), this means that the degree of energy fragmentation due to crystal cleavage is further increased by the unique structure of the matrix. The fact that the emitted light is efficiently expressed in a wide wavelength band according to the substitution of the metal ion is an effect due to the unique structure itself of the matrix.

The phosphors according to an embodiment of the present invention may include at least one metal ion selected from the group consisting of Bi (III), Eu (III), Mn (II), Tb (III) And the metal ions are represented by M in the composition formula. General composition formula of the phosphor containing matrix is _{Ba 9-x M x Y 2} Si 6 O 24, the composition fed ratio of the M x may be less than 0.0015 to 1.85.

In particular, Figs. 2 to 5, which will be described below, provide detailed information on excitation light or emitted light of a phosphor doped with Bi (III) and a phosphor doped with Bi (III) and Eu (III) . The formula of the phosphor is Ba _{9-3 (m + n) / 2} Bi _m Eu _n Y ₂ Si ₆ O ₂₄ , 0.001? M? 0.1 and 0? N? 0.1.

A phosphor represented by the formula Ba _{9-3 (m + n) / 2} Bi _m Eu _n Y ₂ Si ₆ O ₂₄ (with 0.001 ≤ m ≤ 0.1 and 0 ≤ n ≤ 0.1) and Ba ₉ Y _2-mn Bi _m Eu _n Si ₆ O ₂₄ - (0.001 ≦ m ≦ 0.1 and 0 ≦ n ≦ 0.1 are satisfied) can be obtained by appropriately adjusting the stoichiometric amount of BaCO ₃ (99.8%, Alfa), Y ₂ O ₃ (99.9%, Alfa), SiO ₂ (99.5%, Alfa), Bi ₂ O ₃ (99.99%, Aldrich) and Eu ₂ O ₃ After mixing, 2.5wt% of Li ₂ CO ₃ (99%, Alfa) is added as a flux and heated to 1100 in air for 3 hours, so that it can be obtained easily and efficiently. Embodiments obtained through the above-described method are described in detail below.

2 is a diagram showing the wavelength band of the excitation light, the wavelength band of the emitted light, and the intensity of the fluorescent material in which Bi (III) is substituted for the matrix according to the embodiment of the present invention.

FIG. 2 (a) shows information on the excitation light source of the doped phosphor by substituting Ba (II) for Bi (III) and information about the emitted light. It can be seen that the band of the excitation wavelength appears from approximately 330 nm to approximately 380 nm. The phosphor excited by an excitation light source having a center wavelength of approximately 332 nm emits light having a center wavelength of approximately 490 nm in accordance with the Stokes transition. On the other hand, a phosphor excited by an excitation light source having a center wavelength of approximately 373 nm emits light having a center wavelength of approximately 409 nm.

FIG. 2 (b) shows information on the excitation light source of the doped phosphor and information on the emitted light by substituting Y (III) for Bi (III). The phosphor excited by an excitation light source having a center wavelength of approximately 332 nm emits light having a center wavelength of approximately 490 nm in accordance with the Stokes transition. On the other hand, a phosphor excited by an excitation light source having a center wavelength of approximately 373 nm emits light having a center wavelength of approximately 409 nm.

Fig. 2 (c) shows the change in luminescence intensity depending on the composition ratio of Bi (III) in the above-mentioned phosphor. It can be confirmed that the emission intensity is maximized when m is 0.025 in both cases where Bi (III) is substituted for Ba (II) and Y (). This tendency is confirmed both in the case where the central wavelength of the emitted light is approximately 409 nm and in the case of approximately 490 nm. It can also be seen that the emission intensity of the phosphor obtained by substituting Bi (III) with Y () is stronger than the emission light of the phosphor obtained by substituting Ba (II) for Bi (III).

FIG. 3 is a diagram showing the wavelength band of the excitation light and the wavelength band and intensity of the emitted light of the phosphor in which Bi (III) and Eu (III) are substituted for the matrix according to the embodiment of the present invention. The center wavelength of the excitation light is approximately 332 nm and approximately 373 nm as in Fig.

Figures 3 (a) and 3 (b) provide detailed information on emission light when Bi (III) is substituted for Ba (II). It can be confirmed that further emission of Eu (III) at about 615 nm is further expressed by the additional doping of Eu (III).

However, it can be confirmed that the intensity of the emitted light with a center wavelength of about 409 nm and the intensity of emitted light with a center wavelength of about 490 nm become weaker at the time of further doping of Eu (III). The intensity of the emitted light having a center wavelength of about 409 nm and the emitted light having a center wavelength of about 490 nm was the maximum when n was 0.005 and the intensity of emitted light having a center wavelength of about 615 nm was the maximum when n was 0.1.

3 (c) and 3 (d) provide detailed information on emission light when Bi (III) is substituted for Y (III). 3 (a) and Fig. 3 (b), the metal ion substitutes Y (Ⅲ) instead of Ba (Ⅱ) as shown in Fig. 2 (c) Can observe the enhanced emitted light.

3 (a) and 3 (b), the intensity of emitted light with a center wavelength of about 409 nm and emission light with a center wavelength of about 490 nm are weakened at the time of further doping of Eu (III) Can be confirmed. The intensity of the emitted light having a center wavelength of about 409 nm and the emitted light having a center wavelength of about 490 nm was the maximum when n was 0.005 and the intensity of emitted light having a center wavelength of about 615 nm was the maximum when n was 0.1.

Fig. 4 is a diagram showing the CIE chromaticity distribution of phosphors in which Bi (III) and Eu (III) are substituted for a matrix according to an embodiment of the present invention. FIG. 4 shows a color coordinate change of emission light at a change in the ratio of n when the formula is Ba _{9-3 (m + n) / 2} Bi _m Eu _n Y ₂ Si ₆ O ₂₄ and m is 0.025. It can be confirmed that when Ba (II) is substituted for Bi (III) to Eu (III), white light is realized especially when n is 0.05 (coordinate D). The CIE coordinates of D are x = 0.305 and y = 0.312. Even when Y (III) is substituted for Bi (III) to Eu (III), white light can be realized. X = 0.280 and y = 0.319 of the coordinate C that implements white light. At this time, n is 0.01.

)의 변화에 대한 도시이다. 에너지는 감광제인 Bi(Ⅲ)에서 활성제인 Eu(Ⅲ)로 전달된다. 도 5의 (a)는 Bi(Ⅲ)가 Ba(Ⅱ)을 치환하여 도핑되어 있고 상기 Bi(Ⅲ)의 구성비가 0.025로 고정되었을 때, Eu(Ⅲ)의 비율 변화에 따른 Bi(Ⅲ)에서 Eu(Ⅲ)로의 에너지 전달 효율의 변화를 나타낸다. Eu(Ⅲ)의 구성비가 증가할수록 에너지 전달 효율 또한 증가한다. 특히 Eu(Ⅲ)의 구성비가 0.1일 때 에너지 전달 효율은 0.8을 상회한다. 도 5의 (d)는 Bi(Ⅲ)가 Y()를 치환하여 도핑되어 있고 상기 Bi(Ⅲ)의 구성비가 0.025로 고정되었을 때, Eu(Ⅲ)의 비율 변화에 따른 에너지 전달 효율의 변화를 나타낸다. Eu(Ⅲ)의 구성비가 증가할수록 에너지 전달 효율이 증가한다. 특히 Eu(Ⅲ)의 구성비가 0.1일 때 에너지 전달 효율은 0.8을 상회한다.Fig. 5 is a graph showing the energy transfer efficiency (Fig. 5) of a phosphor substituted by Bi (III) and Eu (III)

). ≪ / RTI > The energy is transferred from the sensitizer Bi (Ⅲ) to the active Eu (Ⅲ). 5 (a) is a graph showing changes in the ratio of Eu (III) to Bi (III) when Bi (III) is doped with Ba (II) substituted and the composition ratio of Bi (III) And the energy transfer efficiency to Eu (III). As the composition ratio of Eu (III) increases, the energy transfer efficiency also increases. In particular, when the composition ratio of Eu (III) is 0.1, the energy transfer efficiency exceeds 0.8. 5 (d) shows a change in the energy transfer efficiency due to the change in the ratio of Eu (III) when Bi (III) is doped with Y () replaced and the composition ratio of Bi (III) is fixed at 0.025 . As the composition ratio of Eu (III) increases, energy transfer efficiency increases. In particular, when the composition ratio of Eu (III) is 0.1, the energy transfer efficiency exceeds 0.8.

)에 대해서는 다음의 공식이 성립한다.

는 활성제의 존재 하에서 감광제의 발광 강도를 의미하며,

는 활성제의 부재 하에서 감광제의 발광강도를 의미한다.Energy transfer efficiency

), The following formula is established.

Quot; means the light emission intensity of the photosensitizer in the presence of the activator,

Quot; means the light emission intensity of the photosensitizer in the absence of an activator.

의 변화에 따른

값의 선형 함수로 표현될 수 있다.

은 Bi(Ⅲ)와 Eu(Ⅲ)의 농도이며,

값이 3일 때에는 에너지 전달이 교환 작용에 의한다는 것을 의미하고,

값이 6일 때에는 에너지 전달이 작용에 의한다는 것을 의미한다. 도 5의 (b)와 (c), 및 도 5의 (e)와 (f)를 종합하면, 감광제인 Bi(Ⅲ)에서 활성제인 Eu(Ⅲ)로의 에너지전달이 비방사성 교환작용에 의한 것임을 나타낸다.Figures 5 (b) and 5 (c) and Figures 5 (e) and 5 (f) provide information on energy transfer mechanisms. In this case, according to Dexter's theory, the energy transfer mechanism

With changes in

Can be expressed as a linear function of the value.

Is the concentration of Bi (III) and Eu (III)

When the value is 3, it means that the energy transfer is due to the exchange action,

A value of 6 means that energy transfer is due to action. 5 (b) and 5 (c), and 5 (e) and 5 (f) show that energy transfer from Bi (III) as a sensitizer to Eu (III) as an activator is due to non- .

6 to 9, which will be described below, show a phosphor doped with Ce (III), Mn (II) and Tb (III), and a phosphor doped with Ce (III), Mn (II) and Tb And provides detailed information on excitation light or emitted light of the phosphor. The formula of the phosphor is Ba _{9-3 (m / 2) -n-3 (p / 2)} Ce _m Mn _n Tb _p Y ₂ Si ₆ O ₂₄ and is a single phase, 0.005 ≤ m ≤ 0.4, 0 ≤ n ≤ 0.5, and 0? P? 0.5.

A _{phosphor of the} formula Ba _{9-3m / 2-n-3p / 2} Ce _m Mn _n Tb _p Y ₂ Si ₆ O ₂₄ (provided that 0.005 ≤ m ≤ 0.4, 0 ≤ n ≤ 0.5 and 0 ≤ p ≤ 0.5 and.) is appropriate stoichiometric amounts of BaCO ₃ (99.8% in consideration of the composition according to the respective _{embodiments, Alfa), Y 2 O 3} (99.9%, Alfa), SiO 2 (99.5%, Alfa), CeO 2 ( 99.9%, Alfa), MnO ( 99%, Aldrich) , and _{Tb 4 O 11 (99.9%,} Alfa) was added to the mixture after the reduction _{Li 2 CO 3 (99%,} Alfa) of 2.5wt% as a flux (flux) It can be obtained easily and efficiently by heating for 3 hours at 950 and 1100 in the atmosphere (4% H ₂ gas / 96% Ar gas). Embodiments obtained through the above-described method are described in detail below.

FIG. 6 is a diagram showing the wavelength band of the excitation light and the wavelength band and intensity of the emitted light of the phosphor in which Ce (III), Mn (II) and Tb (III) are substituted respectively in the matrix according to the embodiment of the present invention.

FIG. 6 (a) is a _{graph showing} that the chemical formula is Ba _8.85 Ce _0.1 Y ₂ Si ₆ O ₂₄ , Ba _8.25 Tb _0.5 Y ₂ Si ₆ O ₂₄ , and Ba _8.5 Mn _0.5 Y ₂ Si ₆ O ₂₄ phosphors. It can be seen that the wavelength band of the excitation is wide from approximately 270 nm to approximately 360 nm. The phosphor having the formula Ba _8.85 Ce _0.1 Y ₂ Si ₆ O ₂₄ emits blue light and the phosphor having the formula Ba _8.5 Mn _0.5 Y ₂ Si ₆ O ₂₄ emits red light and has the formula Ba _8.25 Tb _0.5 Y ₂ Si ₆ O ₂₄ -phosphor emits green light. The absorption and emission spectra of phosphors having the formula Ba _8.5 Mn _0.5 Y ₂ Si ₆ O ₂₄ were shown to be 50 times the actual measured intensity. FIG. 6 (b) shows the characteristics of the excited and emitted light of phosphors doped together with Ce (III), Mn (II) and Tb (III). Emitted light is expressed in a broad wavelength band from approximately 360 nm to approximately 650 nm. The emission intensity at around 610 nm was increased by doping both Ce (III), Mn (II) and Tb (III), and it was confirmed that blue light, red light and green light were all expressed.

FIG. 7 is a diagram showing the wavelength band of the excitation light and the wavelength band and intensity of the emitted light of the phosphor in which Ce (III), Mn (II) and Tb (III) are substituted for the matrix according to the embodiment of the present invention. 7 (a) and 7 (b) show detailed information on changes in excitation light or emitted light according to the composition ratio of phosphors doped together with Ce (III), Mn (II) and Tb .

As can be observed in Fig. 6 (b), it is consistent that the emitted light is all expressed in the region of the tricolor light. It can be seen that the excitation of the phosphor occurs in a wavelength band from approximately 250 nm to approximately 370 nm.

FIG. 7 (a) shows detailed information on changes in excitation light or emission light when the composition ratio of Ce (III) is fixed to 0.1 and the composition ratios of Mn (II) and Tb (III) are different. _{(P / 2)} Ce _0.1 Mn _n Tb _p Y ₂ Si ₆ O ₂₄ , where n is 0.1, 0.3, 0.5 and the p independent of n is 0.1, 0.3, 0.5 . As the ratio of Tb (III) increases, the degree of blue light emission by Ce (III) decreases. Mn (Ⅱ) shows a tendency that the emission ratio of red light increases as the composition ratio increases.

FIG. 7 (b) provides detailed information on changes in the excitation light or emission light when the composition ratio of Ce (III) is fixed to 0.025 and the composition ratios of Mn (II) and Tb (III) are different. _{(P / 2)} Ce _0.025 Mn _n Tb _p Y ₂ Si ₆ O ₂₄ , where n is 0.1, 0.3, 0.5 and the p independent of n is 0.1, 0.3, 0.5 . As shown in FIG. 7 (a), as the ratio of Tb (III) increases, the degree of blue light emission by Ce (III) decreases. Mn (Ⅱ) shows a tendency that the emission ratio of red light increases as the composition ratio increases.

FIG. 7 (c) shows the intensity variation of the emitted light obtained by doping Ce (III) and Mn (II) together when the composition ratio of Tb (III) is 0.1. When the composition ratio of Ce (III) is 0.1 and the composition ratio of Mn (II) is 0.3, the intensity of emitted light is maximized. If the composition ratio of Ce (III) is 0.025, the intensity of emitted light is maximized when the composition ratio of Mn (II) is 0.5. If Mn (Ⅱ) has the same composition ratio, Ce (Ⅲ) has a composition ratio of Ce (Ⅲ) of 0.025 as compared with that of Ce (Ⅲ) of 0.1.

FIG. 7 (d) shows a change in intensity of emitted light obtained by doping Ce (III) and Tb (III) together when the composition ratio of Mn (II) is 0.1. When the composition ratio of Ce (III) is 0.025 and the composition ratio of Tb (III) is 0.3, the intensity of emitted light is maximized. If the composition ratio of Ce (III) is 0.1, the intensity of emitted light is maximized when the composition ratio of Tb (III) is 0.5.

)의 변화에 대한 도시이다. 에너지는 Ce(Ⅲ)에서 Mn(Ⅱ) 혹은 Tb(Ⅲ)으로 전달된다. 에너지 전달 효율(

)에 대해서는 다음의 공식이 성립한다.

는 활성제의 존재 하에서 감광제의 발광 강도를 의미하며,

는 활성제의 부재 하에서 감광제의 발광강도를 의미한다.FIG. 8 is a graph showing the energy transfer efficiencies of phosphors substituted with Ce (III), Mn (II) and Tb (III)

). ≪ / RTI > Energy is transferred from Ce (III) to Mn (II) or Tb (III). Energy transfer efficiency

), The following formula is established.

Quot; means the light emission intensity of the photosensitizer in the presence of the activator,

Quot; means the light emission intensity of the photosensitizer in the absence of an activator.

8 (a) shows the energy transfer efficiency change depending on the ratio of Ce (III) to Mn (II) when the composition ratio of Tb (III) is fixed at 0.1. When the composition ratio of Ce (III) is 0.1 or 0.025, the energy transfer efficiency increases as the composition ratio of Mn (II) increases. FIG. 8 (b) shows a change in energy transfer efficiency depending on the ratio of Ce (III) to Tb (III) when the composition ratio of Mn (II) is fixed at 0.1. When the composition ratio of Ce (III) is 0.1 or 0.025, the energy transfer efficiency increases as the composition ratio of Tb (III) increases.

의 변화에 따른

값의 선형 함수로 표현될 수 있다.

은 Mn(Ⅱ)의 농도이며,

값이 6일 때에는 에너지 전달이 쌍극자-쌍극자 상호작용에 의한다는 것을 의미하고,

값이 8일 때에는 에너지 전달이 쌍극자-사중극자 상호작용에 의한다는 것을 의미하며,

값이 10일 때에는 에너지 전달이 사중극자-사중극자 상호작용에 의한다는 것을 의미한다. 도 8(c)는 감광제인 Ce(Ⅲ)에서 활성제인 Mn(Ⅱ)로의 에너지전달이 비방사성의 쌍극자-쌍극자 상호작용에 의한 것임을 나타낸다. 도 8(d)와 도 8(e)를 종합하면, 사중극자-사중극자 상호작용 보다는 쌍극자-사중극자 상호작용이 에너지 전달에 관여하고 있는 것을 확인할 수 있다.Figures 8 (c) through 8 (e) provide information on the energy transfer mechanism. In this case, according to Dexter's theory, the energy transfer mechanism

With changes in

Can be expressed as a linear function of the value.

Is the concentration of Mn (II)

A value of 6 means that energy transfer is due to dipole-dipole interactions,

A value of 8 means that energy transfer is due to dipole-quadrupole interaction,

A value of 10 means that energy transfer is due to quadrupole-quadrupole interaction. Figure 8 (c) shows that the energy transfer from the photosensitizer Ce (III) to the activator Mn (II) is due to the nonradiative dipole-dipole interactions. 8 (d) and 8 (e), it can be seen that dipole-quadrupole interaction is involved in energy transfer rather than quadrupole-quadrupole interaction.

FIG. 9 is a graph showing CIE chromaticity distributions of phosphors in which Ce (III), Mn (II), and Tb (III) are substituted for a matrix according to an embodiment of the present invention. It can be confirmed that white light can be realized by adjusting the composition ratio of Ce (III), Mn (II) and Tb (III). Especially, when the composition ratios of Ce (Ⅲ) and Mn (Ⅱ) are fixed at 0.1 and 0.1 and the composition ratio of Tb (III) is increased, When the phosphor has a formula of Ba ₈ Ce _0.1 Mn _0.1 Tb _0.5 Y ₂ Si ₆ O ₂₄ , emission light located at coordinates C (x = 0.279, y = 0.242) close to white light can be confirmed.

On the other hand, FIGS. 10 to 15, which will be described below, provide information on the characteristics of phosphors obtained by further doping Na (I) together with Eu (III) and Mn (II) . Unlike Eu (Ⅲ) and Mn (Ⅱ), which act as photosensitizers or activators, Na (Ⅰ) plays a role in changing the crystal structure by substituting Ba (Ⅱ).

Ba _{8.9- (1/2) p} Na _p Eu _0.1 Y ₂ Si ₆ O ₂₄ (where 0 ≤ p ≤ 0.8) Ba _8.7-q Na _0.4 Eu _0.1 Mn _q Y ₂ Si ₆ O ₂₄ phosphor (where, satisfies 0 ≤ q ≤ 0.4.) is ₃ (99.8%, Alfa) of the appropriate stoichiometric amount, taking into account the composition of the respective examples BaCO, Y ₂ O ₃ (99.9 _{%, Alfa), SiO 2 (} 99.5%, Alfa), Eu 2 O 3 (99.9%, Alfa), MnO (99%, Aldrich) and back flux (flux) mixture of _{Na 2 CO 3 (99.5%,} Alfa) (99% Alfa) with 2.5 wt% of Li ₂ CO ₃ and heating it at 950 and 1100 for 3 hours in a reducing atmosphere (4% H ₂ gas / 96% Ar gas) . Embodiments obtained through the above-described method are described in detail below.

10 is a diagram showing the wavelength band of the excitation light and the wavelength band and intensity of the emitted light of the phosphor in which Na (I) and Eu (III) are substituted for the matrix according to the embodiment of the present invention. FIG. 10 provides detailed information on the excitation light and the emitted light of the phosphor that can be obtained when Eu (III) and Na (I) are substituted in the matrix. The phosphor may be excited by light in a broad wavelength band from about 240 nm or more to about 460 nm or less. As the composition ratio of Na (Ⅰ) increases, the center wavelength of emitted light shifts to a long wavelength. As the composition ratio of Na (Ⅰ) increases, the yellow light gradually becomes clear.

FIG. 11 is a view showing an open-type change of emitted light according to the substitution ratio of Na (I) to a matrix according to an embodiment of the present invention. Referring to FIG. 11, the reason why the central wavelength shifts to a longer wavelength as the composition ratio of Na (I) increases can be explained. Figures 11 (a) to 11 (c) show the spectrum of the measured emission light divided by three Gaussian profiles through Gaussian deconvolution. The graphs indicated by Ba (1) in Figs. 11 (a) to 11 (c) show the effect of the Ba (II) site in which oxygen is 12 coordinated. The graphs indicated by Ba (2) in Figs. 11 (a) to 11 (c) show the effect of the 9 (Ba) (II) coordination site on oxygen. In the same vein, the graph shown by (3) in Fig. 11 (a) to Fig. 11 (c) shows the effect of oxygen on the position of Ba (Ⅱ) coordinated to 10 coordination.

11 (a) is information on emission light when p is 0 when the formula of the phosphor is Ba _{8.9- (1/2) p} Na _p Eu _0.1 Y ₂ Si ₆ O ₂₄ , and FIG. 11 ) Is information on emitted light when p is 0.4, and FIG. 11 (c) is information on emitted light when p is 0.8. As the composition ratio of Na (Ⅰ) increases, the emission band of Ba (2) and Ba (3) increases faster than the emission band of Ba (1). This is because the radius of Na (Ⅰ) is relatively small and Ba (Ⅱ) with a low coordination number can be more appropriately substituted. 11 (a) emits light with a center wavelength of approximately 500 nm because of the fact that the activator of Ba _8.9 Eu _0.1 Y ₂ Si ₆ O ₂₄ , which is doped only with Eu (III) Because. However, as the composition ratio of Na (Ⅰ) increases, the crystal structure of the mother changes and the length between Eu (Ⅲ) and coordination oxygen decreases. As a result, the influence of the crystal field increases, and the central wavelength shifts to the long wavelength region as shown in FIG. 11 (c).

FIG. 12 is a diagram showing the wavelength band of the excitation light and the wavelength band and intensity of the emitted light of the phosphor in which Na (I), Eu (III) and Mn (II) are substituted in the matrix according to the embodiment of the present invention.

Fig. 12 shows the relationship between the excitation light and the emission light of phosphors doped together with Eu (III) and Mn (II) together with phosphors doped with Eu (III), Mn (II) and Na The illustrated spectra are disclosed. All of the phosphors were excited in a broad wavelength band from about 250 nm or more to about 460 nm or less. In both of the above cases, it can be seen that as the composition ratio of Mn (II) increases, the specific gravity of emitted light by Eu (III) decreases. Particularly, in the phosphors doped with Eu (III), Mn (II) and Na (I) together, the CIE color coordinates of light emitted when q was 0.1 were x = 0.453 and y = 0.445. The CIE color coordinates of the emitted light were x = 0.538, y = 0.414. As a result of Na (Ⅰ) substitution, it can be confirmed that the influence of emitted light expressed by Mn (Ⅱ) is increased.

FIG. 13 is a diagram showing an open-type change of emitted light according to the change of the Mn (II) substitution ratio of a phosphor in which Na (I), Eu (III), and Mn (II) are substituted in the matrix according to an embodiment of the present invention. Detailed information on the emitted light of the phosphor doped with Eu (III), Na (I) and Mn (II) is provided to the matrix. As the composition ratio of Mn (II) increases, the intensity of emission light due to Eu (III) becomes weaker. On the other hand, the emitted light having a center wavelength of approximately 610 nm had a maximum emission intensity in a phosphor having the formula Ba _8.4 Na _0.4 Eu _0.1 Mn _0.3 Y ₂ Si ₆ O ₂₄ .

)의 변화에 대한 도시이다. 화학식이 Ba_8.4Na_0.4Eu_0.1Mn_qY₂Si₆O₂₄인 형광체에서 Mn(Ⅱ)의 구성비를 달리하여 에너지 전달 효율(

)을 측정한 결과가 개시되고 있다. 에너지는 Eu(Ⅲ)에서 Mn(Ⅱ)로 전달된다. q의 값이 증가할수록 전달 효율도 꾸준히 증가하는 경향성을 보였다. 특히 q가 0.4일 때, 에너지 전달 효율은 81%에 달하였다. 에너지 전달 효율(

)에 대해서는 다음의 공식이 성립한다.

는 활성제의 존재 하에서 감광제의 발광 강도를 의미하며,

는 활성제의 부재 하에서 감광제의 발광강도를 의미한다.Fig. 14 is a graph showing the energy transfer efficiency (Fig. 14) of a phosphor substituted with Na (I), Eu (III), and Mn

). ≪ / RTI > In the phosphors of formula Ba _8.4 Na _0.4 Eu _0.1 Mn _q Y ₂ Si ₆ O ₂₄ , Mn (Ⅱ)

) Are measured. Energy is transferred from Eu (III) to Mn (II). As the value of q increases, the transmission efficiency tends to increase steadily. In particular, when q was 0.4, the energy transfer efficiency reached 81%. Energy transfer efficiency

), The following formula is established.

Quot; means the light emission intensity of the photosensitizer in the presence of the activator,

Quot; means the light emission intensity of the photosensitizer in the absence of an activator.

의 변화에 따른

값의 선형 함수로 표현될 수 있다.

은 Mn(Ⅱ)의 농도이며,

값이 6일 때에는 에너지 전달이 쌍극자-쌍극자 상호작용에 의한다는 것을 의미하고,

값이 8일 때에는 에너지 전달이 쌍극자-사중극자 상호작용에 의한다는 것을 의미한다. 도 14의 (b)와 도 14의 (c)를 종합하면, 감광제인 Eu(Ⅲ)에서 활성제인 Mn(Ⅱ)로의 에너지전달이 비방사성의 쌍극자-쌍극자 상호작용에 의한 것임을 나타낸다.Figs. 14 (b) to 14 (c) provide information on the energy transfer mechanism. In this case, according to Dexter's theory, the energy transfer mechanism

With changes in

Can be expressed as a linear function of the value.

Is the concentration of Mn (II)

A value of 6 means that energy transfer is due to dipole-dipole interactions,

A value of 8 means that energy transfer is due to dipole-quadrupole interaction. 14 (b) and 14 (c) show that energy transfer from Eu (III) as a sensitizer to Mn (II) as an activator is due to nonradiative dipole-dipole interactions.

FIG. 15 is a diagram showing the CRI and the color temperature (CCT) of a phosphor in which Na (I), Eu (III), and Mn (II) are substituted in the matrix according to an embodiment of the present invention. FIG. 15 provides details of emission light emitted as a result of excitation of each phosphor by near-ultraviolet rays. The color rendering index (CRI) of emitted light expressed by the phosphor represented by Ba _8.9 Eu _0.1 Y ₂ Si ₆ O ₂₄ is 85.0, the color temperature (CCT) is 5312 K, and the CIE color coordinates are x = 0.3086 and y = 0.3974. The color rendering index (CRI) of the emitted light expressed by the phosphor represented by Ba _8.7 Na _0.4 Eu _0.1 Y ₂ Si ₆ O ₂₄ is 86.1, the color temperature (CCT) is 4866 K and the CIE color coordinates are x = 0.3559 and y = 0.4163. (CRI) of 91.6, the color temperature (CCT) of 3274 K and the CIE color coordinates of x = 0.4137 and y = 0.3852, which are expressed by the phosphor represented by Ba _8.6 Na _0.4 Eu _0.1 Mn _0.1 Y ₂ Si ₆ O ₂₄ , to be. This means that the near ultraviolet rays are excited in the phosphor substituted by Na (I) to effectively emit warm-white emission light.

{Example}

Hereinafter, the LED phosphors that emit white light will be described in more detail with reference to Examples.

Example 1

Samples were prepared by mixing appropriate stoichiometric amounts of BaCO ₃ , Y ₂ O ₃ , SiO ₂ , Bi ₂ O ₃ and Eu ₂ O ₃ .

Then, 2.5 wt% of Li ₂ CO ₃ was added, and the mixture was heated to 1100 in an air atmosphere for 3 hours.

Thus, a phosphor having the formula Ba _8.8875 Bi _0.025 Eu _0.05 Y ₂ Si ₆ O ₂₄ was prepared.

Example 2

In Example 1, samples were prepared by adding appropriate stoichiometric amounts of CeO ₂ , MnO and Tb ₄ O ₁₁ instead of Bi ₂ O _3- and Eu ₂ O ₃ , and a reducing atmosphere (4% H ₂ gas / 96% Ar gas) at 950 and 1100 for 3 hours to prepare a phosphor of the formula Ba ₈ Ce _0.1 Mn _0.1 Tb _0.5 Y ₂ Si ₆ O _24- .

Comparative Example 1

In the same manner as in Example 1 except that Bi ₂ O _{3 -} was added in the _{absence of} Eu ₂ O ₃ , the same procedure as in Example 1 was _repeated except that Ba _8.9625 Bi _0.025 Y ₂ Si ₆ O ₂₄ To prepare a phosphor.

Comparative Example 2

In Example 2, phosphors of the formula Ba _8.6 Ce _0.1 Mn _0.1 Tb _0.1 Y ₂ Si ₆ O ₂₄ were prepared by the same procedure except that CeO ₂ , MnO and Tb ₄ O ₁₁ were added in different amounts.

Table 1 summarizes the phosphors of Examples 1 and 2 and Comparative Examples 1 and 2.

Table 1 division The prepared phosphor Example 1 Ba _8.8875 Bi _0.025 Eu _0.05 Y ₂ Si ₆ O ₂₄ Example 2 Ba ₈ Ce _0.1 Mn _0.1 Tb _0.5 Y ₂ Si ₆ O ₂₄ Comparative Example 1 Ba _8.9625 Bi _0.025 Y ₂ Si ₆ O ₂₄ Comparative Example 2 Ba _8.6 Ce _0.1 Mn _0.1 Tb _0.1 Y ₂ Si ₆ O ₂₄

{evaluation}

1. The degree of expression of white light

In order to evaluate the degree of expression of white light, the chromaticity distributions of the phosphors of Examples 1, 2, and 1 were used.

The evaluation results are shown in Fig. 4 and Fig.

4 is a graph showing the color of emitted light based on the CIE chromaticity distribution for the phosphor of Example 1 and Comparative Example 1. Fig.

Among the sample phosphors, the phosphor of Example 1 emits the most clear white light, and the CIE chromaticity distribution coordinates were x = 0.305 and y = 0.312. On the other hand, the chromaticity coordinates of the emitted light emitted from the phosphor of Comparative Example 1 were x = 0.185 and y = 0.289, which were distant from the white light.

9 is a graph showing the color of emitted light based on the CIE chromaticity distribution for the phosphor prepared in Example 2 and the phosphor prepared in Comparative Example 2. FIG.

The phosphor of Example 2 emits white light having coordinates of x = 0.279 and y = 0.242 on the CIE chromaticity distribution. On the other hand, the phosphor of Comparative Example 2 expresses a purple light having coordinates of x = 0.202 and y = 119 on the CIE chromaticity distribution.

From the above description, it can be confirmed that the phosphors according to Examples 1 and 2 exhibit excellent white light in the degree of white light emission.

) 2. Evaluation of energy transfer efficiency

)

The energy transfer efficiency was evaluated by comparing the change in the light emission intensity of the photosensitizer depending on the presence or absence of the activator.

Referring to FIG. 5 (a), it can be seen that the energy transfer efficiency of the phosphor of Example 1 exceeds 80%. 8 (b), it can be confirmed that the energy transfer efficiency of the phosphor of Example 2 has a value very close to 80%.

On the other hand, referring to FIG. 5 (a), it can be confirmed that the energy transfer efficiency of the phosphor of Comparative Example 1 is slightly higher than 40%. Referring to FIG. 8 (b), it is confirmed that the energy transfer efficiency of the phosphor of Comparative Example 2 is also slightly higher than 40%.

The phosphors of Examples 1 and 2 exhibit white light unlike the phosphors of Comparative Examples 1 and 2. In particular, the phosphors of Examples 1 and 2 exhibit energy transfer efficiency And 80%, respectively. It can be said that the phosphor for LED utilizing ultraviolet ray to near ultraviolet ray has very excellent luminescence characteristics.

As described above, the host of the novel structure disclosed in the present invention is a host having a structure of at least one of Bi (III), Eu (III), Ce (III), Mn (II), Tb (III) And can emit light of various wavelength bands. In addition, a phosphor having an energy transfer efficiency of 80% or more can be obtained by adjusting the composition ratio appropriately.

In particular, as described in one embodiment of the present invention, by substituting Bi (III) and Eu (III) in the mother body at an appropriate ratio, white light can be realized by a single phosphor alone (see FIG. 4). In addition, as described in one embodiment of the present invention, white light can be realized by only a single phosphor by replacing Ce (III), Mn (II) and Tb (III) In addition, as described in one embodiment of the present invention, it is possible to obtain a phosphor having near ultraviolet rays as an excitation light source by substituting Na (I), Eu (III) and Mn (II) And emits white light efficiently (see Fig. 15).

The present invention is not limited by the above-described embodiments and the accompanying drawings, but is intended to be limited only by the appended claims. It will be apparent to those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. something to do.

Claims (14)

Yttrium-orthosilicate having a trigonal structure and expressed by the composition formula Ba _9-x M _x Y ₂ Si ₆ O ₂₄ ,
Wherein M is at least one selected from the group consisting of Bi, Eu, Ce, Mn, Tb, and Na, and 0.0015? X? 1.85.
The method according to claim 1,
Wherein M includes at least two elements selected from the group, and the two or more elements satisfy the condition that 0.0015? X? 1.85.
The method according to claim 2,
(II), 9-coordinated Ba (II), and 10-coordinated Ba (II) in the matrix.
The method of claim 3,
(1) < / RTI >

&Lt; Formula 1 >
Ba _{9-3 (m + n) / 2} Bi _m Eu _n Y ₂ Si ₆ O ₂₄
However, the condition of 0.001? M? 0.1 and 0? N? 0.1 is satisfied.
5. The method of claim 4,
Wherein the excitation wavelength is 330 nm or more and 380 nm or less.
The method of claim 3,
(2): &quot; (2) &quot;

(2)
Ba _{9-3 (m / 2) -n-3 (p / 2)} Ce _m Mn _n Tb _p Y ₂ Si ₆ O ₂₄
However, the condition of 0.005? M? 0.4, 0? N? 0.5, and 0? P? 0.5 is satisfied.
The method according to claim 6,
Wherein the excitation wavelength is from 270 nm or more to 360 nm or less.
The method of claim 3,
(3). &Lt; EMI ID = 3.0 >

(3)
Ba _{9- (1 / 2p) -q} Na _p M _q Y ₂ Si ₆ O ₂₄
In the above formula (3), M is at least one selected from the group consisting of Bi, Eu, Ce, Mn, Tb and Na, and satisfies 0? P? 0.8 and 0.0015? Q? 1.05.
The method of claim 3,
(4): < EMI ID = 6.1 >

&Lt; Formula 4 >
Ba _{8.9 - (1 / 2p) -q} Na _p Eu _0.1 Mn _q Y ₂ Si ₆ O ₂₄
However, the condition of 0? P? 0.8 and 0? Q? 0.8 is satisfied.
10. The method of claim 9,
Wherein the excitation wavelength is 250 nm or more and 470 nm or less.
Yttrium-orthosilicate having a trigonal structure and expressed by the composition formula Ba ₉ M _y Y _{2 -y} Si ₆ O ₂₄ ,
Wherein M is at least one species selected from the group consisting of Bi and Eu, and 0.001? Y? 0.2.
12. The method of claim 11,
(II), 9-coordinated Ba (II), and 10-coordinated Ba (II) in the matrix.
13. The method of claim 12,
(5): < EMI ID = 6.0 >

&Lt; Formula 5 >
Ba ₉ Y _{2-m n} Bi _m Eu _n Si ₆ O ₂₄
However, the condition of 0.001? M? 0.1 and 0? N? 0.1 is satisfied.
14. The method of claim 13,
Wherein the excitation wavelength is 330 nm or more and 380 nm or less.

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