KR102432030B1 - Lgiht emitting device - Google Patents

Abstract

In an embodiment, a light emitting device emitting a first light; and a wavelength conversion layer for converting the wavelength of the first light, wherein the wavelength conversion layer includes: a first wavelength conversion body absorbing the first light and emitting light in a green wavelength band; and a second wavelength converter that absorbs the first light and emits light in a red wavelength band, wherein the second wavelength converter satisfies the following structural formula.
[constitutional formula]
K ₂ M _1-x Mn ⁴⁺ _X F ₆
Here, M is at least one element selected from the group consisting of a group 4 element and a group 14 element, and X satisfies 0.028≤X≤0.055.

Description

Light emitting device {LGIHT EMITTING DEVICE}

The embodiment relates to a light emitting device.

A light emitting device (LED) is a compound semiconductor device that converts electric energy into light energy, and various colors can be realized by adjusting the composition ratio of the compound semiconductor.

The nitride semiconductor light emitting device has advantages of low power consumption, semi-permanent lifespan, fast response speed, safety, and environmental friendliness compared to conventional light sources such as fluorescent lamps and incandescent lamps. Therefore, a light emitting diode backlight that replaces a Cold Cathode Fluorescence Lamp (CCFL) constituting the backlight of a liquid crystal display (LCD) display device, a white light emitting diode lighting device that can replace a fluorescent lamp or an incandescent light bulb, and a car headlight And the application is expanding to traffic lights.

The light emitting device may realize white light by combining a light emitting device (a light emitting chip) and a phosphor. Recently, a K ₂ SiF ₆ phosphor has been studied as a red phosphor. However, when white light is implemented using such a fluoride phosphor, a problem in which color coordinates change under a high-temperature environment may occur.

The embodiment provides a fluoride phosphor having excellent reliability and a light emitting device using the fluoride phosphor.

The problem to be solved in the embodiment is not limited thereto, and it will be said that the purpose or effect that can be grasped from the solving means or embodiment of the problem described below is also included.

A light emitting device according to an embodiment of the present invention includes: a light emitting element emitting a first light; and a wavelength conversion layer that converts the wavelength of the first light, wherein the wavelength conversion layer includes: a first wavelength conversion body that absorbs the first light and emits light in a green wavelength band; and a second wavelength converter that absorbs the first light and emits light in a red wavelength band, wherein the second wavelength converter may satisfy the following structural formula.

[constitutional formula]

K ₂ M _{1 - x} Mn ^{4 +} _X F ₆

Here, M is at least one element selected from the group consisting of a group 4 element and a group 14 element, and X satisfies 0.028≤X≤0.055.

The wavelength conversion layer may include a light-transmitting resin in which the first wavelength converter and the second wavelength converter are dispersed.

The total amount of the first wavelength converter and the second wavelength converter based on 100wt% of the composition of the wavelength conversion layer may be 25wt% to 50wt%.

Based on 100 wt% of the composition of the wavelength conversion layer, the total amount of the first wavelength converter and the second wavelength converter may be 25 wt% to 45 wt%.

The content ratio of the first wavelength converter may be 25% to 40%, and the content ratio of the second wavelength converter may be 60% to 75%.

The molar ratio of Mn of the second wavelength converter may be 0.04 mol to 0.055 mol.

The total amount of the first wavelength converter and the second wavelength converter based on 100wt% of the composition of the wavelength conversion layer may be 30wt% to 50wt%.

The content ratio of the first wavelength converter may be 15% to 30%, and the content ratio of the second wavelength converter may be 70% to 85%.

The molar ratio of Mn of the second wavelength converter may be 0.028 mole to 0.0399 mole.

According to an embodiment, a change in Cx of the light emitting device may be controlled. Accordingly, the reliability of the light emitting device can be improved.

Various and advantageous advantages and effects of the present invention are not limited to the above, and will be more easily understood in the course of describing specific embodiments of the present invention.

1 is a conceptual diagram of a light emitting device according to an embodiment of the present invention;
2 is a graph of measuring the color coordinates of white light implemented using a red phosphor having a molar ratio of Mn of 100% and 75%;
3 is a graph of measuring the luminous flux of white light implemented using a red phosphor having a molar ratio of Mn of 100% and 75%;
4 is a graph of measuring the spectrum of white light implemented using a red phosphor having a molar ratio of Mn of 100% and 75%;
5 is a graph of measuring the color coordinates of white light implemented using a red phosphor having a molar ratio of Mn of 100% and 50%;
6 is a graph of measuring the luminous flux of white light implemented using a red phosphor having a molar ratio of Mn of 100% and 50%;
7 is a graph of measuring a spectrum of white light implemented using a red phosphor having a molar ratio of Mn of 100% and 50%;
8 is a graph of measuring the color coordinates of white light implemented using a red phosphor having a molar ratio of Mn of 100% and 30%;
9 is a graph of measuring the luminous flux of white light implemented using a red phosphor having a molar ratio of Mn of 100% and 30%;
10 is a graph of measuring a spectrum of white light implemented using a red phosphor having a molar ratio of Mn of 100% and 30%;
11 is a graph of measuring the spectrum of a red phosphor with the molar ratio of Mn adjusted to 100%, 75%, and 50%.
12 is a graph measuring the change in the luminous flux of white light using a red phosphor having a molar ratio of Mn of 100%, 75%, and 50% under a condition of 60°C;
13 is a graph measuring the change in Cx color coordinates of white light using a red phosphor having a molar ratio of Mn of 100%, 75%, and 50% under a condition of 60°C;
14 is a graph showing the change in Cy color coordinates of white light using a red phosphor having a molar ratio of Mn of 100%, 75%, and 50% under a condition of 60°C;
15 is a graph showing the change in the luminous flux of white light using a red phosphor having a molar ratio of Mn of 100%, 75%, and 50% under a condition of 80°C;
16 is a graph showing the change in Cx color coordinates of white light using a red phosphor having a molar ratio of Mn of 100%, 75%, and 50% under a condition of 80°C;
17 is a graph measuring the change in Cy color coordinates of white light using a red phosphor having a molar ratio of Mn of 100%, 75%, and 50% under a condition of 80°C;
18 is a graph showing the change in the luminous flux of white light using a red phosphor having a molar ratio of Mn of 100%, 75%, and 50% under a condition of 80°C/85%;
19 is a graph measuring the change in Cx color coordinates of white light using a red phosphor having a molar ratio of Mn of 100%, 75%, and 50% under a condition of 80°C/85%;
20 is a graph measuring the change in Cy color coordinates of white light using a red phosphor having a molar ratio of Mn of 100%, 75%, and 50% under a condition of 80°C/85%;
21 is a conceptual diagram of the light emitting device of FIG. 1,
22 is a conceptual diagram of a light emitting device package according to an embodiment of the present invention.

Since the present invention may have various changes and may have various embodiments, specific embodiments will be illustrated and described in the drawings. However, this is not intended to limit the embodiment of the present invention to a specific embodiment, and it should be understood to include all changes, equivalents, or substitutes included in the spirit and scope of the embodiment.

Terms including an ordinal number, such as first, second, etc., may be used to describe various elements, but the elements are not limited by the terms. The above terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the second component may be referred to as the first component, and similarly, the first component may also be referred to as the second component. and/or includes a combination of a plurality of related listed items or any of a plurality of related listed items.

The terms used in the present application are only used to describe specific embodiments, and are not intended to limit the embodiments of the present invention. The singular expression includes the plural expression unless the context clearly dictates otherwise. In the present application, terms such as "comprise" or "have" are intended to designate that a feature, number, step, operation, component, part, or combination thereof described in the specification exists, but one or more other features It is to be understood that it does not preclude the possibility of the presence or addition of numbers, steps, operations, components, parts, or combinations thereof.

In the description of the embodiment, in the case where one element is described as being formed on "on or under" of another element, on (above) or below (on) or under) includes both elements in which two elements are in direct contact with each other or one or more other elements are disposed between the two elements indirectly. In addition, when expressed as "up (up) or down (on or under)", it may include the meaning of not only an upward direction but also a downward direction based on one element.

Hereinafter, the embodiment will be described in detail with reference to the accompanying drawings, but regardless of the reference numerals, the same or corresponding components are given the same reference numerals, and the overlapping description thereof will be omitted.

1 is a conceptual diagram of a light emitting device according to an embodiment of the present invention.

Referring to FIG. 1 , the light emitting device of the embodiment includes a light emitting device 100 emitting a first light L1 and a wavelength conversion layer 200 absorbing a portion of the first light L1 to emit light.

The light emitting device 100 may be a blue light emitting device emitting light of 420 nm to 470 nm or a UV light emitting device emitting light in an ultraviolet wavelength band. The structure of the light emitting device 100 is not particularly limited.

The wavelength conversion layer 200 includes a first wavelength converter 201 , a second wavelength converter 202 , and a light-transmitting resin 204 in which they are dispersed. The structure of the wavelength conversion layer 200 is not limited.

The wavelength conversion layer 200 may be disposed only on the top surface of the light emitting device 100 , or may be disposed on the top surface and side surfaces of the light emitting device 100 . Alternatively, the light emitting device 100 may be entirely molded by filling the cavity of the package.

The light-transmitting resin 204 may be at least one selected from the group consisting of an epoxy resin, a silicone resin, a polyimide resin, a urea resin, and an acrylic resin, but is not limited thereto.

The first light L1 emitted from the light emitting device 100 and the light converted by the wavelength conversion layer 200 may be mixed to implement the white light L2 on the CIE color coordinates.

The first wavelength converter 201 may partially absorb the first light L1 to emit light in a green wavelength band. Light in the green wavelength band may have a peak at 525 nm to 545 nm, and a full width at half maximum (FWHM) may be 45 nm to 55 nm.

The first wavelength converter 201 is a β (beta) type SiAlON:Eu, BaYSi ₄ N ₇ :Eu, Ba ₃ Si ₆ O ₁₂ N ₂ :Eu, CaSi ₂ O ₂ N ₂ :Eu, SrYSi ₄ N ₇ : Eu, LuAG, and may include at least one.

The second wavelength converter 202 may partially absorb the first light L1 to emit light in a red wavelength band. Light in the red wavelength band may have a peak at 630 nm to 635 nm, and a full width at half maximum (FWHM) of 5 nm to 10 nm. The second wavelength converter may be a fluoride phosphor satisfying the following structural formula.

[constitutional formula]

K ₂ M _1-x Mn ⁴⁺ _X F ₆

Here, M may be at least one element selected from the group consisting of a group 4 element and a group 14 element. For example, M may be Si or Ti. X may satisfy 0.028≤X≤0.055. That is, the molar ratio of the activating element Mn may be 0.024 mole to 0.055 mole. Hereinafter, for convenience of explanation, the second wavelength converter will be described as a red phosphor represented by K ₂ SiF ₆ :Mn ^{4 +} .

When the molar ratio of Mn is 0.04 mol to 0.055 mol, the total amount of the first wavelength converter 201 and the second wavelength converter 202 based on 100 wt% of the composition of the wavelength conversion layer may be 25 wt% to 45 wt% . For example, when the total amount of the first wavelength converter and the second wavelength converter is 40 wt%, the content of the light-transmitting resin 204 may be 60 wt%.

In this case, the content ratio of the first wavelength converter 201 may be 25% to 40%, and the content ratio of the second wavelength converter 202 may be 60% to 75%. When these conditions are satisfied, white light can be implemented in the CIE coordinate system. In addition, as will be described later, it is possible to improve the Cx color coordinate deviation.

When the molar ratio of Mn is 0.028 mol to 0.0399 mol, the total amount of the first wavelength converter 201 and the second wavelength converter 202 based on 100 wt% of the composition of the wavelength conversion layer may be 30 wt% to 50 wt% . In this case, the content ratio of the first wavelength converter 201 may be 15% to 30%, and the content ratio of the second wavelength converter 202 may be 70% to 85%. When these conditions are satisfied, white light may be realized in the CIE coordinate system by mixing with the light of the light emitting device. In addition, it is possible to improve the Cx color coordinate deviation of the package.

Hereinafter, a case in which the molar ratio of Mn is 0.07 mol is defined as Mn: 100%, 0.525 mol is Mn: 75%, 0.035 mol is Mn: 50%, and 0.021 mol is Mn: 30%.

2 is a graph of measuring the color coordinates of white light implemented using red phosphors having Mn molar ratios of 100% and 75%, and FIG. 3 is implemented using red phosphors having Mn molar ratios of 100% and 75%. It is a graph measuring the luminous flux of one white light, and FIG. 4 is a graph measuring the spectrum of white light realized using a red phosphor having a molar ratio of Mn of 100% and 75%.

In the comparative example, white light was implemented using a blue light emitting device, a beta SiAlON green phosphor, and a red phosphor having Mn: 100%. In the first embodiment, white light was realized using a blue light emitting device, a green phosphor of beta SiAlON, and a red phosphor having Mn: 75%.

Table 1 below is a table measuring the luminous flux (Flux), CIE color coordinates, color reproducibility (NTSC), and wavelength peak (WP) of white light implemented by Comparative Example and Example 1, and Table 2 shows the phosphor compounding ratio. is a table

division
phosphor Flux
(lm) Flux
(%) Cx
Cy
NTSC
(%) WP
(nm) Green Red comparative example
Beta
SiAlON KSF
Mn: 100% 13.7 100.0 0.268 0.265 89.8 447.4 first embodiment KSF
Mn:75% 13.5 98.6 0.268 0.265 88.8 446.4

division light transmissive resin
Phosphor compound ratio (%) Total
(wt%) Green
Beta-SiAlON KSF
Mn: 100% KSF
Mn: 75% comparative example silicon
20.9 33.5 66.5 - first embodiment 25.2 31.2 - 68.8

As shown in FIG. 2 , it can be seen that both the white light of the comparative example and the first example are white light in the CIE coordinate system. In addition, as shown in FIG. 3 and Table 1, it can be seen that the luminous flux of Example 1 is almost the same as that of Comparative Example.

Referring to Table 2, it can be seen that in Comparative Example, the total amount of the phosphor was 20.9 wt% based on 100 wt% of the total composition, whereas in Example 1, the total amount was increased to 25.2 wt%. In addition, in the case of Example 1, it can be seen that the content ratio of the red phosphor was 68.8%, which was slightly increased compared to the Comparative Example.

That is, when the molar ratio of Mn of the red phosphor is decreased, it can be seen that the total amount of the phosphor increases and the content of the red phosphor increases in order to maintain white light on the CIE coordinates.

5 is a graph of measuring the color coordinates of white light implemented using red phosphors having Mn molar ratios of 100% and 50%, and FIG. 6 is implemented using red phosphors having Mn molar ratios of 100% and 50%. It is a graph measuring the luminous flux of one white light, and FIG. 7 is a graph of measuring the spectrum of white light realized using a red phosphor having a molar ratio of Mn of 100% and 50%.

In Comparative Example, white light was implemented using a blue light emitting device, a green phosphor of beta SiAlON, and a red phosphor having Mn: 100%. In the second embodiment, white light was realized by using a blue light emitting device, a green phosphor of beta SiAlON, and a red phosphor having Mn: 50%.

Table 3 below is a table measuring the luminous flux, CIE color coordinates, color reproducibility (NTSC), and wavelength peak (WP) of white light implemented by Comparative Example and Example 2, and Table 4 is a table showing the phosphor compounding ratio.

division
phosphor Flux
(lm) Flux
(%) Cx
Cy
NTSC
(%) WP
(nm) Green Red comparative example
Beta
SiAlON
KSF
Mn: 100% 11.96 100 0.245 0.220 91.0 446.7 second embodiment KSF
Mn: 50% 12.07 100.9 0.244 0.220 90.7 446.5

division light transmissive resin
Phosphor compound ratio (%) Total
(wt%) Green
Beta-SiAlON KSF
Mn: 100% KSF
Mn: 50% comparative example silicon
20.0 32 68 - second embodiment 33.0 18.5 - 81.5

As shown in FIG. 5 , it can be seen that both the white light of the comparative example and the second example are white light in the CIE coordinate system. 6 and Table 3, it can be seen that the luminous flux of the second example is almost the same as that of the comparative example.

Referring to Table 4, it can be seen that in Comparative Example, the total amount of the phosphor was 20.0 wt% based on 100 wt% of the total composition, whereas in Example 2, the total amount was increased to 33.0 wt%. In addition, in the case of the second embodiment, it can be seen that the content ratio of the red phosphor is 81.5%, which is increased compared to the comparative example.

It can be seen that in Example 2 using Mn: 50%, the total amount of the entire phosphor and the content of the red phosphor were further increased compared to Example 1.

8 is a graph of measuring the color coordinates of white light implemented using red phosphors having Mn molar ratios of 100% and 30%, and FIG. 9 is implemented using red phosphors having Mn molar ratios of 100% and 30%. It is a graph measuring the luminous flux of one white light, and FIG. 10 is a graph of measuring the spectrum of white light realized using a red phosphor having a molar ratio of Mn of 100% and 30%.

In Comparative Example, white light was implemented using a blue light emitting device, a green phosphor of beta SiAlON, and a red phosphor having Mn: 100%. In the third embodiment, white light was realized by using a blue light emitting device, a green phosphor of beta SiAlON, and a red phosphor having an Mn: 30%.

Table 5 below is a table measuring the luminous flux, CIE color coordinates, color reproducibility (NTSC), and wavelength peak (WP) of white light implemented by Comparative Example and Example 3, and Table 6 is a table showing the phosphor compounding ratio.

division
phosphor Flux
(lm) Flux
(%) Cx
Cy
NTSC
(%) WP
(nm) Green Red comparative example
Beta
SiAlON
KSF
Mn: 100% 15.92 100 0.259 0.248 87.0 447.9 3rd embodiment KSF
Mn: 30% 15.55 97.4 0.259 0.248 86.6 447.9

division light transmissive resin
Phosphor compounding ratio (%) Total
(wt%) Green
Beta-SiAlON KSF
Mn: 100% KSF
Mn: 30% comparative example silicon
28.5 31.5 68.5 - 3rd embodiment 91.0 10.5 - 89.5

As shown in FIG. 8 , it can be seen that both the first white light and the second white light are white light in the CIE coordinate system. However, referring to FIGS. 9 and 5 , it can be seen that the luminous flux of Example 3 was reduced by about 2.3% compared to Comparative Example.

In Comparative Example, it can be seen that the total amount of the phosphor was 28.0 wt% based on 100 wt% of the total composition, whereas in Example 3, the total amount was 91.0 wt%, which was very high. In addition, in the case of the third embodiment, it can be seen that the content ratio of the red phosphor is 89.5%, which is very high compared to the comparative example.

Therefore, when the Mn molar ratio is lowered to 30% or less, the luminous flux may be lowered, and the total amount of the phosphor may be excessively increased. In this case, reliability problems may arise.

11 is a graph of measuring the spectrum of a red phosphor with the Mn molar ratio adjusted to 100%, 75%, and 50%.

Table 7 below is a table measuring the wavelength peak (WP), relative luminance, half width, and incident size according to the molar ratio of Mn.

division wavelength peak
[nm] Relative luminance
(%) half width
[nm] Particle size [㎛] D10 D50 D90 D90-D10 KSF-Mn 100% 632 100 7 18 26 40 22 KSF-Mn 75% 632 91 7 18 26 40 22 KSF-Mn 50% 632 77 7 18 26 40 22

Referring to Table 7 and FIG. 11, when the luminance of the red phosphor having Mn: 100% is 100, the relative luminance of the red phosphor having Mn: 75% is 91%, and the relative luminance of the red phosphor having Mn: 50% is It can be seen that the decrease is 77%. However, it can be seen that the full width at half maximum, the wavelength peak, and the particle size are substantially the same.

12 is a graph illustrating the change in luminous flux of white light using a red phosphor having a molar ratio of Mn of 100%, 75%, and 50% under a condition of 60° C., and FIG. 13 is a molar ratio of Mn of 100%, 75 %, 50% of white light using a red phosphor of which the Cx color coordinate changes under a condition of 60° C. is a graph, and FIG. 14 is a graph showing white light using a red phosphor having a molar ratio of 100%, 75%, and 50% of Mn It is a graph measuring the change of Cy color coordinates under the condition of 60°C.

Referring to FIG. 12 , in the third embodiment using the red phosphor having Mn: 50%, it can be seen that the change in the luminous flux of white light is relatively low. On the other hand, in the case of Comparative Example using a red phosphor having Mn: 100% and Example 1 using a red phosphor having Mn: 75%, it can be seen that the decrease in the luminous flux increases as time elapses.

Referring to FIG. 13 , in the case of the third embodiment, it can be seen that the variation width of the Cx coordinates of white light is the lowest. In the case of the comparative example, it can be seen that the range of change of the Cx coordinates with the passage of time is the largest.

Therefore, it can be seen that when the molar ratio of Mn of the red phosphor is lowered, the reliability of the package can be improved. However, the Mn molar ratio of the red phosphor and the total amount of the phosphor may have an inverse relationship. That is, as the molar ratio of Mn decreases, the Cx change rate decreases, but the amount of the phosphor used may increase.

However, referring to FIG. 14 , it can be seen that the change widths of the Cy coordinates are relatively similar in the comparative example, the first example, and the second example all over time.

Similar results were obtained even when the deviation of the luminous flux, Cx color coordinate, and Cy color coordinate was measured by raising the temperature to 80° C. as shown in FIGS. 15 to 17 . In addition, similar results were obtained even under conditions of high temperature/high humidity (80°C/85%) as shown in FIGS. 18 to 20 .

21 is a conceptual diagram of the light emitting device of FIG. 1 , and FIG. 22 is a conceptual diagram of a light emitting device package according to an embodiment of the present invention.

Referring to FIG. 21 , the substrate 110 of the light emitting device 100 includes a conductive substrate or an insulating substrate. The substrate 110 may be a material suitable for semiconductor material growth or a carrier wafer. The substrate 110 may be formed of a material selected from among sapphire (Al ₂ O ₃ ), SiC, GaAs, GaN, ZnO, Si, GaP, InP, and Ge, but is not limited thereto.

The buffer layers 111 and 112 may alleviate a lattice mismatch between the light emitting structure provided on the substrate 110 and the substrate 110 . The buffer layers 111 and 112 may be grown as single crystals on the substrate 110 , and the buffer layers 111 and 112 grown as single crystals may improve crystallinity of the first semiconductor layer 130 .

The light emitting structure provided on the substrate 110 includes a first semiconductor layer 130 , an active layer 140 , and a second semiconductor layer 160 . In general, the light emitting structure as described above may be separated into a plurality of pieces by cutting the substrate 110 .

The first semiconductor layer 130 may be a group III-V or group II-VI compound semiconductor, and the first semiconductor layer 130 may be doped with a first dopant. The first semiconductor layer 130 is a semiconductor material having a composition formula of In _x1 Al _y1 Ga ₁ -x1 _-y1 N (0≤x1≤1, 0≤y1≤1, 0≤x1+y1≤1), for example, It may be selected from GaN, AlGaN, InGaN, InAlGaN, and the like. In addition, the first dopant may be an n-type dopant such as Si, Ge, Sn, Se, or Te. When the first dopant is an n-type dopant, the first semiconductor layer 130 doped with the first dopant may be an n-type semiconductor layer.

The active layer 140 is a layer in which electrons (or holes) injected through the first semiconductor layer 130 and holes (or electrons) injected through the second semiconductor layer 160 meet. The active layer 140 may transition to a low energy level as electrons and holes recombine, and may generate light having a corresponding wavelength. In this embodiment, there is no limitation on the emission wavelength.

The active layer 140 may have any one of a single well structure, a multi-well structure, a single quantum well structure, a multi-quantum well (MQW) structure, a quantum dot structure, or a quantum wire structure, and the active layer 140 . The structure is not limited thereto.

The active layer 140 may have a structure in which a plurality of well layers and barrier layers are alternately disposed. The well layer and the barrier layer may have a compositional formula of InxAlyGa1-x-yN (0≤x≤1, 0≤y≤1, 0≤x+y≤1), and the energy bandgap of the barrier layer is the energy of the well layer. It may be larger than the band gap.

The second semiconductor layer 160 is formed on the active layer 140 , and may be implemented as a compound semiconductor such as III-V or II-VI, and the second semiconductor layer 160 may be doped with a second dopant. can The second semiconductor layer 160 is a semiconductor material having a composition formula of In _x5 Al _y2 Ga _{1 -x5- y2} N (0≤x5≤1, 0≤y2≤1, 0≤x5+y2≤1) or AlInN, AlGaAs , GaP, GaAs, GaAsP, may be formed of a material selected from AlGaInP. When the second dopant is a p-type dopant such as Mg, Zn, Ca, Sr, or Ba, the second semiconductor layer 160 doped with the second dopant may be a p-type semiconductor layer.

An electron blocking layer (EBL) 150 may be disposed between the active layer 140 and the second semiconductor layer 160 . The electron blocking layer 150 blocks the flow of electrons supplied from the first semiconductor layer 130 from escaping to the second semiconductor layer 160 , thereby increasing the probability of recombination of electrons and holes in the active layer 140 . have. The energy bandgap of the electron blocking layer 150 may be greater than the energy bandgap of the active layer 140 and/or the second semiconductor layer 160 .

The electron blocking layer 150 is a semiconductor material having a composition formula of In _x1 Al _y1 Ga ₁ -x1 _-y1 N (0≤x1≤1, 0≤y1≤1, 0≤x1+y1≤1), for example, AlGaN. , InGaN, InAlGaN, etc., but is not limited thereto.

The first electrode 180 may be formed on the partially exposed first semiconductor layer 130 . In addition, the second electrode 170 may be formed on the second semiconductor layer 160 . As the first electrode 180 and the second electrode 190 , various metal and transparent electrodes may be applied.

The first electrode 180 and the second electrode 170 are In, Co, Si, Ge, Au, Pd, Pt, Ru, Re, Mg, Zn, Hf, Ta, Rh, Ir, W, Ti, Ag, It may include any one of a metal selected from Cr, Mo, Nb, Al, Ni, Cu, and WTi. If necessary, an ohmic electrode layer may be further included.

Referring to FIG. 22 , the light emitting device package 10 according to the embodiment includes a first lead frame 11 , a second lead frame 12 , a light emitting device 100 , a wavelength conversion layer 200 , and a body 13 . ) is included.

The light emitting device 100 may be a light emitting device having various structures emitting light in a blue or ultraviolet wavelength band. In addition, the structure described with reference to FIG. 21 may be applied to the light emitting device 100 as it is.

The light emitting device 100 may be electrically connected to the first lead frame 11 and the second lead frame 12 . Electrical connection between the light emitting device 100 and the first and second lead frames 11 and 12 may be determined by an electrode structure (vertical or horizontal) of the light emitting device.

The body 13 includes a cavity 13a that fixes the first lead frame 11 and the second lead frame 12 and exposes the light emitting device 100 . The body 13 may include a polymer resin such as polyphthalamide (PPA).

The wavelength conversion layer 200 is disposed in the cavity 13a and includes first and second wavelength conversion elements 201 and 202 . The first and second wavelength converters 201 and 202 may be dispersed in the light-transmitting resin 204 . The wavelength conversion layer 200 may include the above-described characteristics as it is.

The light emitting device or light emitting device package of the embodiment may further include an optical member such as a light guide plate, a prism sheet, and a diffusion sheet to function as a backlight unit. In addition, the light emitting device of the embodiment may be further applied to a display device, a lighting device, and an indicator device.

In this case, the display device may include a bottom cover, a reflector, a light emitting module, a light guide plate, an optical sheet, a display panel, an image signal output circuit, and a color filter. The bottom cover, the reflector, the light emitting module, the light guide plate, and the optical sheet may form a backlight unit.

The reflector is disposed on the bottom cover, and the light emitting module emits light. The light guide plate is disposed in front of the reflection plate to guide light emitted from the light emitting module to the front, and the optical sheet includes a prism sheet and the like, and is disposed in front of the light guide plate. The display panel is disposed in front of the optical sheet, an image signal output circuit supplies an image signal to the display panel, and a color filter is disposed in front of the display panel.

In addition, the lighting device may include a light source module including a substrate and the light emitting device of the embodiment, a heat dissipation unit for dissipating heat of the light source module, and a power supply unit for processing or converting an electrical signal provided from the outside and providing it to the light source module. . Furthermore, the lighting device may include a lamp, a head lamp, or a street lamp.

The embodiments of the present invention described above are not limited to the above-described embodiments and the accompanying drawings, but various substitutions, modifications and changes are possible within the scope without departing from the technical spirit of the embodiments. It will be clear to those with prior knowledge in

100: light emitting device
200: wavelength conversion layer
201: first wavelength converter
202: second wavelength converter
204: light-transmitting resin

Claims (9)

a light emitting device emitting a first light; and
A wavelength conversion layer for converting the wavelength of the first light,
The wavelength conversion layer,
a first wavelength converter that absorbs the first light and emits light in a green wavelength band;
a second wavelength converter that absorbs the first light and emits light in a red wavelength band; and
and a light-transmitting resin in which the first and second wavelength converters are dispersed,
The second wavelength converter is a light emitting device that satisfies the following structural formula:
[constitutional formula]
K ₂ M _1-x Mn ⁴⁺ _X F ₆
Here, M is at least one element selected from the group consisting of a group 4 element and a group 14 element, and X satisfies 0.028≤X≤0.055,
When the molar ratio of Mn is 0.04 mol to 0.055 mol, the total amount of the first wavelength converter and the second wavelength converter based on 100 wt% of the composition of the wavelength conversion layer is 25 wt% to 45 wt%,
The content ratio of the first wavelength converter is 25% to 40%, and the content ratio of the second wavelength converter is 60% to 75%. a light emitting device emitting a first light; and
A wavelength conversion layer for converting the wavelength of the first light,
The wavelength conversion layer,
a first wavelength converter that absorbs the first light and emits light in a green wavelength band;
a second wavelength converter that absorbs the first light and emits light in a red wavelength band; and
and a light-transmitting resin in which the first and second wavelength converters are dispersed,
The second wavelength converter is a light emitting device that satisfies the following structural formula:
[constitutional formula]
K ₂ M _1-x Mn ⁴⁺ _X F ₆
Here, M is at least one element selected from the group consisting of a group 4 element and a group 14 element, and X satisfies 0.028≤X≤0.055,
As the molar ratio of Mn is lower, the total amount of the first wavelength converter and the second wavelength converter increases, and the content of the second wavelength converter in the first wavelength converter and the second wavelength converter increases. do. 3. The method of claim 1 or 2,
When the molar ratio of Mn is 0.028 mol to 0.0399 mol, the total amount of the first wavelength converter and the second wavelength converter based on 100 wt% of the composition of the wavelength conversion layer is 30 wt% to 50 wt%,
The content ratio of the first wavelength converter is 15% to 30%, and the content ratio of the second wavelength converter is 70% to 85%. 3. The method of claim 1 or 2,
The first wavelength converter has a peak at 525 nm to 545 nm and emits light in the green wavelength band having a full width at half maximum (FWHM) of 45 nm to 55 nm,
The second wavelength converter has a peak at 630 nm to 635 nm and a light emitting device emitting light in the red wavelength band having a full width at half maximum (FWHM) of 5 nm to 10 nm. delete delete delete delete delete

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