KR20140063067A - Phosphor compositions - Google Patents

Abstract

An embodiment of the present invention relates to a phosphor composition and a light emitting device including the same. The phosphor composition according to the embodiment of the present invention is represented by an empirical formula of A_3-zC_5O_12 : RE_z (0<z<=0.5). A includes at least one element among Y, Sc, Gd and Lu. C includes at least one element among boron (B), Al and Ga. RE includes at least one element among Eu, Ce, Sm, Yb, Dy, Gd, Tm and Lu. The empirical formula of A_3-zC_5O_12 : RE_z can include (Y, Gd)_3-z(B, Al)_5O_12.

Description

PHOSPHOR COMPOSITIONS [0001]

An embodiment relates to a phosphor composition and a light emitting device including the phosphor composition. The light emitting device may include a light emitting device package, a lighting unit, a backlight unit, or the like.

A light emitting device is a device in which electric energy is converted into light energy. For example, an LED can be implemented in various colors by controlling a composition ratio of a compound semiconductor.

For example, nitride semiconductors have received great interest in the development of optical devices and high power electronic devices due to their high thermal stability and wide bandgap energy. Particularly, blue light emitting devices, green light emitting devices, ultraviolet (UV) light emitting devices, and the like using nitride semiconductors have been commercialized and widely used.

An LED emitting white light is a method of using a secondary light source that emits light from a phosphor by applying a phosphor, and a method of obtaining a white light by applying a YAG: Ce phosphor that emits yellow to a blue LED is generally used.

However, this method has a disadvantage in that it is accompanied by quantum deficits generated by using secondary light and efficiency reduction due to the re-emission efficiency, and color rendering is not easy.

Accordingly, a conventional white LED backlight is a combination of a blue LED chip and a yellow phosphor, and is limited in the extent that it can be used for a screen of a mobile phone or a notebook PC because green and red components are lacking and therefore unnatural colors are expressed. Nevertheless, it is widely commercialized because of its advantages of being easy to drive and being remarkably inexpensive.

In general, it is widely known that phosphors use silicates, phosphates, aluminates or sulfides as matrix materials and transition metals or rare earth metals as luminescent centers. For example, silicate phosphors are used for BLU and illumination, and silicate phosphors are vulnerable to moisture, which causes a problem of poor reliability characteristics compared with other phosphors.

On the other hand, in recent years, development of phosphors which emit visible light by excitation by an excitation source having a high energy such as ultraviolet light or blue light has become mainstream in white LEDs. However, when the conventional phosphors are exposed to an excitation source, There is a problem of deterioration.

The embodiment is intended to provide a yellow phosphor of a new composition and a light emitting device including the same.

In addition, the embodiments are intended to provide a phosphor composition with improved reliability and high luminance and a light emitting device including the same.

In addition, the embodiments are intended to provide a phosphor composition having high luminescence intensity and a light emitting device including the phosphor composition.

The phosphor composition according to the embodiment includes A _{3 z} C ₅ O ₁₂ : RE _z A is at least one element selected from the group consisting of Y, Sc, Gd and Lu, and C is at least one element selected from B (boron), Al and Ga RE includes at least one or more elements of Eu, Ce, Sm, Yb, Dy, Gd, Tm and Lu,

The A _{3 z} C ₅ O ₁₂ : RE _z May include (Y, Gd) _3-z (B, Al) ₅ O ₁₂ : Ce _z .

In addition, the phosphor composition according to the embodiment includes A _{3 z} C ₅ O ₁₂ : RE _z A is at least one element selected from the group consisting of Y, Sc, Gd and Lu, and C is at least one element selected from B (boron), Al and Ga RE includes at least one or more elements of Eu, Ce, Sm, Yb, Dy, Gd, Tm and Lu,

The A _{3 z} C ₅ O ₁₂ : RE _z Of the formula _{is, (Gd 3 -y- z Y y} ) B 5 O 12: Ce may include _z (However, 0≤y≤2).

According to the embodiment, a yellow phosphor of a new composition and a light emitting device including the same can be provided.

Further, according to the embodiment, a phosphor composition with improved reliability and high luminance and a light emitting device including the phosphor composition can be provided.

In addition, the embodiment can provide a phosphor composition having high emission intensity and a light emitting device including the same.

1 is a cross-sectional view of a light emitting device package including a phosphor composition according to an embodiment.
2 is a diagram illustrating excitation wavelength characteristic data according to the ratio of Y and Gd in a light emitting device including a phosphor composition according to an embodiment.
3 is a graph showing emission wavelength characteristic data according to the ratio of Y and Gd in the light emitting device including the phosphor composition according to the embodiment.
FIG. 4 shows excitation wavelength characteristic data according to the ratio of Ce in the light emitting device including the phosphor composition according to the embodiment.
FIG. 5 is a graph of emission wavelength characteristic data according to the ratio of Ce in a light emitting device including a phosphor composition according to an embodiment.
6 is an exploded perspective view of a light emitting device including a phosphor composition according to an embodiment.

In the description of the embodiments, it is to be understood that each layer (film), area, pattern or structure may be referred to as being "on" or "under" the substrate, each layer Quot; on "and" under "are intended to include both" directly "or" indirectly " do. Also, the criteria for top, bottom, or bottom of each layer will be described with reference to the drawings.

The thickness and size of each layer in the drawings are exaggerated, omitted, or schematically shown for convenience and clarity of explanation. Also, the size of each component does not entirely reflect the actual size.

(Example)

FIG. 1 is a cross-sectional view of a light emitting device package 200 including a phosphor composition according to an embodiment. The package structure is not limited thereto. The embodiment may be applied to a two cup package.

The light emitting device package 200 according to the embodiment includes a package body 205, a light emitting device chip 100 on the package body 205, and a phosphor composition 232 on the light emitting device chip 100 (Not shown).

The phosphor composition 232 includes A _{3 z} C ₅ O ₁₂ : RE _z A is at least one element selected from the group consisting of Y, Sc, Gd and Lu, and C is at least one element selected from B (boron), Al and Ga And RE may include at least one or more elements of Eu, Ce, Sm, Yb, Dy, Gd, Tm and Lu.

The phosphor composition 232 of the embodiment is a (Y, Gd) _3-z (B, Al) ₅ O ₁₂ : Ce _z (Note that 0 &lt; z? 0.5).

In addition, the embodiment above-mentioned phosphor composition 232 _{(Gd 3 -y- z Y y)} B 5 O 12: Ce may comprise a formula of the composition formula _z (where, 0≤y≤2) in the.

The phosphor composition 232 of the embodiment may have an emission wavelength in the range of 559 nm to 567 nm with respect to the excitation wavelength in the 420 nm to 500 nm region.

The light emitting device package 200 according to the embodiment includes a package body 205, a first electrode layer 213 and a second electrode layer 214 provided on the package body 205, a package body 205, A light emitting device chip 100 mounted on the first electrode layer 213 and the second electrode layer 214 and electrically connected to the first electrode layer 213 and the second electrode layer 214 and a molding member 230 surrounding the light emitting device chip 100 .

The package body 205 may be formed of a silicon material, a synthetic resin material, or a metal material, and the inclined surface may be formed around the light emitting device chip 100.

The first electrode layer 213 and the second electrode layer 214 are electrically isolated from each other and provide power to the light emitting device chip 100. The first electrode layer 213 and the second electrode layer 214 may reflect the light generated from the light emitting device chip 100 to increase the light efficiency. And may also serve to discharge generated heat to the outside.

The light emitting device chip 100 may be a horizontal type light emitting device, but is not limited thereto. Vertical light emitting devices and flip chip type light emitting devices may also be used.

The light emitting device chip 100 may be formed of a nitride semiconductor. For example, the light emitting device chip 100 may be formed of a material such as GaN, GaAs, GaAsP, or GaP.

The light emitting device chip 100 may include a light emitting structure including a first conductive semiconductor layer (not shown), an active layer (not shown), and a second conductive semiconductor layer (not shown).

The first conductive semiconductor layer may be an n-type semiconductor layer, and the second conductive semiconductor layer may be a p-type semiconductor layer. However, the present invention is not limited thereto. Also, on the second conductive semiconductor layer, a semiconductor (e.g., an n-type semiconductor layer) (not shown) having a polarity opposite to that of the second conductive type may be formed. Accordingly, the light emitting structure may have any one of an n-p junction structure, a p-n junction structure, an n-p-n junction structure, and a p-n-p junction structure.

The light emitting device 100 may be disposed on the package body 205 or on the first electrode layer 213 or the second electrode layer 214.

The light emitting device chip 100 may be electrically connected to the first electrode layer 213 and / or the second electrode layer 214 by any one of wire, flip chip, and die bonding methods. Although the light emitting device chip 100 is electrically connected to the first electrode layer 213 through the first wire and the second electrode layer 214 is electrically connected to the second electrode layer 214 through the second wire, It is not.

The molding member 230 surrounds the light emitting device chip 100 to protect the light emitting device chip 100. In addition, the molding member 230 may include a phosphor composition 232 to change the wavelength of light emitted from the light emitting device chip 100.

The phosphor composition 232 of the embodiment has a light emitting region in a yellow region, and can be applied to the application of a white LED.

For example, in the phosphor composition 232 of the embodiment, the excitation light source has an excitation wavelength ranging from 420 nm to 500 nm and may have a yellow emission wavelength in the range of 559 nm to 567 nm according to the absorption region.

The yellow phosphor composition 232 of the embodiment can be applied and utilized for UV-LED and blue LED

For example, a method of applying a blue LED chip and a yellow phosphor composition, a method of applying a green and red phosphor composition 232 on a blue LED chip, a method of forming a green LED on a blue LED chip, , Red, and yellow. The phosphor compositions of the examples are phosphor compositions that emit yellow light, and are phosphor compositions that can be used to realize a white LED.

In the embodiment, a white LED can be realized using a phosphor composition of green, red, and blue in a UV-chip, and the color rendering index can be improved when the yellow phosphor composition is additionally applied thereto.

When a white LED is implemented using the phosphor composition 232 of the embodiment, a white LED can be used in the fields of mobile, automobile, lighting, BLU, medical and the like.

Hereinafter, the manufacturing process of the phosphor composition according to the embodiment will be described and the characteristics of the embodiments will be described in more detail.

The phosphor composition 232 of the embodiment contains A _{3 z} C ₅ O ₁₂ : RE _z A is at least one element selected from the group consisting of Y, Sc, Gd and Lu, and C is at least one element selected from B (boron), Al and Ga And RE may include at least one or more elements of Eu, Ce, Sm, Yb, Dy, Gd, Tm and Lu.

For example, a first embodiment of a phosphor composition 232 _{(Gd 3 -y- z Y y)} B 5 O 12: may comprise the formula (where, 0 <z≤0.5) of Ce _z.

In the case of the phosphor composition 232 according to the embodiment, the solid phase reaction method using a stable starting material is advantageous in that the phosphor composition 232 is easy to manufacture.

For _{example, Y 2 O 3, Gd 2} O 3, B 2 O 3, CeO 2, (Gd 3 -y- z Y y) of a raw material of NH ₄ Cl B ₅ O _12: metering according to the composition ratio of Ce _z After that, the raw material is mixed with agate by using a solvent.

In this case, the range of y is 0? Y? 2, and the raw material can be mixed with the composition according to the ratio of Y and Gd.

Alternatively, the phosphor composition 232 of the second embodiment may be formed of (Y, Gd) _3-z (B, Al) ₅ O ₁₂ : Ce _z May be included.

For example, the raw materials can be mixed according to the change in the ratio of Ce in the basic composition of (Y, Gd) _3-z (B, Al) ₅ O ₁₂ : Ce _z . The ratio range of z may be 0.1? z? 0.3, but is not limited thereto.

At a synthesis temperature of about 1300 ° C. to about 1500 ° C., the gas flow rate is 400 cc to 2,000 cc per minute, and H ₂ , N ₂ , NH ₃ and the like can be used as a reducing gas.

At this time, the phosphor composition 232 can be synthesized by changing the H ₂ / N ₂ mixed gas ratio from 5% / 95% to 20% / 80%.

For example, in the case of the phosphor composition 232 of the embodiment, the reduction gas ratio is in the range of H ₂ -20% / N ₂ -80% at a temperature of about 1400 ° C. for about 6 hours, at a gas flow rate of 1000 cc / But is not limited thereto.

Thereafter, the fired phosphor composition 232 may be dried after being subjected to a ball milling process and a cleaning process using zirconia and a glass ball.

The phosphor composition 232 of the example was confirmed to have particles having an irregular shape with a size of about 10 mu m through SEM data and confirmed the composition of the phosphor composition 232 synthesized through EDX (Energy Dispersive X-ray analyzer) I could.

The dried phosphor composition 232 can analyze the excited light-emitting characteristics over the PL analysis as shown in Fig. 2 and 3, and in accordance with the changing conditions _{(Gd 3 -y- z Y y)} B 5 O 12: Ce z, The blue phosphor composition 232 having an emission wavelength in the range of 559 nm to 567 nm in the case of (Y, Gd) _3-z (B, Al) ₅ O ₁₂ : Ce _z .

2 is excitation wavelength characteristic data according to the ratio of Y and Gd in the light emitting device including the phosphor composition 232 according to the embodiment.

3 is emission wavelength characteristic data according to the ratio of Y and Gd in the light emitting device including the phosphor composition 232 according to the embodiment.

Table 1 shows emissive characteristics according to the ratio of Y and Gd in the light emitting device including the phosphor composition 232 according to the embodiment. Experimental Example The ratio of Y to Gd Furtherance Relative strength Center wavelength (nm) Experimental Example 6 (Spl 6) Y = 0, Gd = 3 Gd ₃ B ₅ O ₁₂ : Ce 100 559 Experimental Example 7 (Spl 7) Y = 1, Gd = 2 Y ₁ Gd ₂ B ₅ O ₁₂ : Ce 87.2 562 Experimental Example 8 (Spl 8) Y = 2, Gd = 1 Y ₂ Gd ₁ B ₅ O ₁₂ : Ce 83.4 567

According to an embodiment _{(Gd 3 -y- z Y y)} B 5 O 12: Ce z When the composition (y) of the composition formula is 0? Y? 2, the reliability and the brightness are high as compared with the prior art, and the optimum luminescence intensity is shown.

Further, according to the embodiment as shown in Figure _{3 (Gd 3 -y- z Y y} ) B 5 O 12: Ce z (Y, Gd) _3-z (B, Al) ₅ O ₁₂ : Ce _z It is possible to provide a yellow phosphor composition of a novel composition capable of emitting yellow light which is not presented in the prior art.

4 is excitation wavelength characteristic data according to the ratio of Ce in the light emitting device including the phosphor composition 232 according to the embodiment.

5 is emission wavelength characteristic data according to the ratio of Ce in the light emitting device including the phosphor composition 232 according to the embodiment.

Experimental Example Ce ratio Furtherance Relative strength Center wavelength (nm) Experimental Example 9 (Spl 9) 0.1 _{(Y, Gd) 3 (B} , Al) 5 O 12: Ce 0 .1 100 559 Experimental Example 10 (Spl 10) 0.2 _{(Y, Gd) 3 (B} , Al) 5 O 12: Ce 0 .2 129.9 560 Experimental Example 11 (Spl 11) 0.3 _{(Y, Gd) 3 (B} , Al) 5 O 12: Ce 0 .3 103.9 564

Table 2 shows emissive characteristics according to the ratio of Ce in the light emitting device including the phosphor composition 232 according to the embodiment.

According to an embodiment, the A _{3 z} C ₅ O ₁₂ : RE _z The composition (z) of RE in the composition formula of RE was higher than that of the conventional art in the case of 0.1? Z? 0.3. Particularly, as shown in Table 2, when the ratio of Ce was 0.2 (Example 10) But the embodiment is not limited to Experimental Example 10.

According to the embodiment, a yellow phosphor of a new composition and a light emitting device including the same can be provided.

Further, according to the embodiment, a phosphor composition with improved reliability and high luminance and a light emitting device including the phosphor composition can be provided.

In addition, the embodiment can provide a phosphor composition having high emission intensity and a light emitting device including the same.

6 is an exploded perspective view of a light emitting device including a phosphor composition according to an embodiment.

The lighting apparatus according to the embodiment may include a cover 2100, a light source module 2200, a heat discharger 2400, a power supply unit 2600, an inner case 2700, and a socket 2800. Further, the illumination device according to the embodiment may further include at least one of the member 2300 and the holder 2500. The light source module 2200 may include a light emitting device or a light emitting device package according to the embodiment.

For example, the cover 2100 may have a shape of a bulb or a hemisphere, and may be provided in a shape in which the hollow is hollow and a part is opened. The cover 2100 may be optically coupled to the light source module 2200 and may be coupled to the heat discharger 2400. The cover 2100 may have an engaging portion that engages with the heat discharging body 2400.

The inner surface of the cover 2100 may be coated with a milky white paint having a diffusion material. The light from the light source module 2200 can be scattered and diffused to emit to the outside using the milky white material.

The cover 2100 may be made of glass, plastic, polypropylene (PP), polyethylene (PE), polycarbonate (PC), or the like. Here, polycarbonate is excellent in light resistance, heat resistance and strength. The cover 2100 may be transparent so that the light source module 2200 is visible from the outside, and may be opaque. The cover 2100 may be formed by blow molding.

The light source module 2200 may be disposed on one side of the heat discharging body 2400. Accordingly, heat from the light source module 2200 is conducted to the heat discharger 2400. The light source module 2200 may include a light emitting device 2210, a connection plate 2230, and a connector 2250.

The member 2300 is disposed on the upper surface of the heat discharging body 2400 and has guide grooves 2310 into which a plurality of illumination elements 2210 and a connector 2250 are inserted. The guide groove 2310 corresponds to the substrate of the illumination device 2210 and the connector 2250.

The surface of the member 2300 may be coated or coated with a white paint. The member 2300 reflects the light reflected by the inner surface of the cover 2100 toward the cover 2100 in the direction toward the light source module 2200. Therefore, the light efficiency of the illumination device according to the embodiment can be improved.

The member 2300 may be made of an insulating material, for example. The connection plate 2230 of the light source module 2200 may include an electrically conductive material. Therefore, electrical contact can be made between the heat discharging body 2400 and the connecting plate 2230. The member 2300 may be formed of an insulating material to prevent an electrical short circuit between the connection plate 2230 and the heat discharging body 2400. The heat discharger 2400 receives heat from the light source module 2200 and heat from the power supply unit 2600 to dissipate heat.

The holder 2500 blocks the receiving groove 2719 of the insulating portion 2710 of the inner case 2700. Therefore, the power supply unit 2600 housed in the insulating portion 2710 of the inner case 2700 is sealed. The holder 2500 has a guide protrusion 2510. The guide protrusion 2510 may have a hole through which the protrusion 2610 of the power supply unit 2600 passes.

The power supply unit 2600 processes or converts an electrical signal provided from the outside and provides the electrical signal to the light source module 2200. The power supply unit 2600 is housed in the receiving groove 2719 of the inner case 2700 and is sealed inside the inner case 2700 by the holder 2500.

The power supply unit 2600 may include a protrusion 2610, a guide 2630, a base 2650, and an extension 2670.

The guide portion 2630 has a shape protruding outward from one side of the base 2650. The guide portion 2630 may be inserted into the holder 2500. A plurality of components may be disposed on one side of the base 2650. The plurality of components may include, for example, a DC converter, a driving chip for controlling driving of the light source module 2200, an ESD (ElectroStatic discharge) protection device for protecting the light source module 2200, The present invention is not limited thereto.

The extension portion 2670 has a shape protruding outward from the other side of the base 2650. The extension portion 2670 is inserted into the connection portion 2750 of the inner case 2700 and receives an external electrical signal. For example, the extension portion 2670 may be provided to be equal to or smaller than the width of the connection portion 2750 of the inner case 2700. The extension 2670 may be electrically connected to the socket 2800 through a wire.

The inner case 2700 may include a molding part together with the power supply part 2600. The molding part is a hardened portion of the molding liquid so that the power supply unit 2600 can be fixed inside the inner case 2700.

According to the embodiment, a yellow phosphor of a new composition and a light emitting device including the same can be provided.

Further, according to the embodiment, a phosphor composition with improved reliability and high luminance and a light emitting device including the phosphor composition can be provided.

In addition, the embodiment can provide a phosphor composition having high emission intensity and a light emitting device including the same.

The features, structures, effects and the like described in the embodiments are included in at least one embodiment and are not necessarily limited to only one embodiment. Furthermore, the features, structures, effects and the like illustrated in the embodiments can be combined and modified by other persons skilled in the art to which the embodiments belong. Accordingly, the contents of such combinations and modifications should be construed as being included in the scope of the embodiments.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by 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. It can be seen that the modification and application of branches are possible. For example, each component specifically shown in the embodiments can be modified and implemented. It is to be understood that the present invention may be embodied in many other specific forms without departing from the spirit or essential characteristics thereof.

205: package body, 100: light emitting device chip
232: phosphor composition, 230: molding member

Claims (5)

A _{3- z} C ₅ O ₁₂ : RE _z (Where 0 &lt; z &amp;le; 0.5)
A comprises at least one or more elements of Y, Sc, Gd and Lu,
C comprises at least one or more elements of B (Boron), Al, and Ga,
RE includes at least one or more elements of Eu, Ce, Sm, Yb, Dy, Gd, Tm and Lu,
The A _{3 z} C ₅ O ₁₂ : RE _z The composition formula of
(Y, Gd) _3-z (B, Al) ₅ O ₁₂ : Ce _z . A _{3- z} C ₅ O ₁₂ : RE _z (Where 0 &lt; z &amp;le; 0.5)
A comprises at least one or more elements of Y, Sc, Gd and Lu,
C comprises at least one or more elements of B (Boron), Al, and Ga,
RE includes at least one or more elements of Eu, Ce, Sm, Yb, Dy, Gd, Tm and Lu,
The A _{3 z} C ₅ O ₁₂ : RE _z The composition formula of
_{(Gd 3 -y- z Y y)} B 5 O 12: Ce phosphor composition comprising at _z (However, 0≤y≤2). 3. The method according to claim 1 or 2,
The above-
And has an emission wavelength in the range of 559 nm to 567 nm with respect to the excitation wavelength in the 420 nm to 500 nm region. The method of claim 3,
(Y, Gd) _3-z (B, Al) ₅ O ₁₂ : Ce _z (Z) of Ce in the composition formula of 0.1? Z? 0.3. 5. The method of claim 4,
(Y, Gd) _3-z (B, Al) ₅ O ₁₂ : Ce _z Wherein the composition (z) of Ce is 0.2.

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