KR20130007169A - Light emitting device - Google Patents

Abstract

PURPOSE: A light emitting device is provided to obtain a high output by efficiently blocking an electron leakage and improving hole injection efficiency. CONSTITUTION: An active layer(114) is formed on a first conductive type semiconductor layer(112) and includes a quantum well(114w) and a quantum wall(114b). An electron blocking layer(130) is formed on the active layer. A second conductive semiconductor layer(116) is formed on the electron blocking layer. The electron blocking layer includes a first electron blocking layer with InN, a second electron blocking layer(132) with AlN, and a third electron blocking layer(133) with GaN.

Description

[0001] LIGHT EMITTING DEVICE [0002]

Embodiments relate to a light emitting device, a method of manufacturing the light emitting device, a light emitting device package and an illumination system.

A light emitting device is a device that converts electrical energy into light energy. For example, the LED can realize various colors by adjusting the composition ratio of the compound semiconductor.

The nitride semiconductor thin film-based light emitting device has advantages of low power consumption, semi-permanent life, fast response speed, safety, and environmental friendliness compared to conventional light sources such as fluorescent and incandescent lamps. Therefore, a light emitting device backlight that replaces a Cold Cathode Fluorescence Lamp (CCFL) constituting a backlight of an LCD (Liquid Crystal Display) display, a white light emitting device lighting device that can replace a fluorescent lamp or an incandescent lamp, and an automobile headlight. And applications have been extended to signals and the like.

Increasing the application range of nitride semiconductor light emitting device basically requires the development of high power and high efficiency technology of the light emitting device.

Meanwhile, according to the related art, in the nitride semiconductor light emitting device having a multi-quantum well structure active layer, the quantum well layers in the active layer do not uniformly disperse the injected carriers, and only a few quantum well layers adjacent to the hole injection layer are mainly used. There is a problem that contributes to light emission. Therefore, when the amount of injection current is large enough, excess electrons are generated which are not effectively bound in the active layer.

These excess electrons do not participate in generating light and self-dissipate in the active layer or leak out of the active layer.

Leakage out of the active layer occurs mainly in the form of a quantum barrier overflow of injected carrier.

In addition, in the conventional nitride semiconductor light emitting device, electrons injected into the active layer have a hot carrier property and thus have a serious carrier overflow problem.

As a result, when the injected current is increased, the non-luminescence loss of electrons and holes is increased, so that the luminous efficiency of the active layer, for example, the internal quantum efficiency is seriously reduced.

Accordingly, according to the related art, an electron blocking layer is formed between the P-GaN layer and the active layer. The electron blocking layer has a larger energy band gap than the quantum wall of the active layer to block electrons supplied from the N-GaN layer from passing through the active layer to the P-GaN layer without participating in light emission.

On the other hand, according to the prior art, the electron blocking layer acts as an energy barrier to holes to be injected into the active layer from the P-GaN layer, which greatly reduces the hole injection efficiency.

On the other hand, in the prior art, there is a problem that the electron blocking layer does not effectively block the leakage of electrons from the active layer toward the P-GaN layer.

Embodiments provide a high output light emitting device, a method of manufacturing a light emitting device, a light emitting device package, and an illumination system.

The light emitting device according to the embodiment includes a first conductivity type semiconductor layer; An active layer formed on the first conductivity type semiconductor layer including a quantum well and a quantum wall; An electron blocking layer on the active layer; A second conductive semiconductor layer on the electron blocking layer, wherein the electron blocking layer comprises: a first electron blocking layer including InN on the active layer; A second electron blocking layer including AlN on the first electron blocking layer; And a third electron blocking layer including GaN on the second electron blocking layer.

In addition, the light emitting device according to the embodiment includes a first conductivity type semiconductor layer; An active layer formed on the first conductivity type semiconductor layer including a quantum well and a quantum wall; An electron blocking layer on the active layer; A second conductive semiconductor layer on the electron blocking layer, wherein the electron blocking layer comprises: an InN electron blocking layer on the active layer; At least one AlN electron blocking layer on the InN electron blocking layer; And at least one GaN electron blocking layer on the AlN electron blocking layer.

According to the light emitting device, the manufacturing method of the light emitting device, the light emitting device package and the illumination system according to the embodiment, it is possible to implement a high output light emitting device by effectively blocking the leakage of electrons while improving the hole injection efficiency.

1 is a schematic diagram of an energy band gap of a light emitting device according to an embodiment;
2 is a conceptual diagram of an electron blocking layer of a light emitting device according to an embodiment;
3 is an exemplary timing diagram for forming an electron blocking layer of a light emitting device according to an embodiment.
4 is a sectional view of a light emitting device according to the embodiment;
5 is a cross-sectional view of a light emitting device package according to an embodiment.
6 is a perspective view of a lighting unit according to the embodiment;
7 is a perspective view of a backlight unit 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. In addition, the size of each component does not necessarily reflect the actual size.

(Example)

1 is a schematic diagram of an energy band gap of a light emitting device according to an embodiment, and FIG. 2 is a conceptual diagram of an electron blocking layer of a light emitting device according to an embodiment.

The light emitting device 100 according to the embodiment (refer to FIG. 4) includes a first conductive semiconductor layer 112, a quantum well 114w and a quantum wall 114b. And an active layer 114 formed on the active layer 114, an electron blocking layer 130 formed on the active layer 114, and a second conductivity-type semiconductor layer 116 formed on the electron blocking layer 130.

In an embodiment, the electron blocking layer 130 is formed on the InN electron blocking layer formed on the active layer 114, at least one AlN electron blocking layer formed on the InN electron blocking layer and the AlN electron blocking layer. At least one GaN electron blocking layer may be included.

For example, the electron blocking layer 130 includes a first electron blocking layer 131 including InN formed on the active layer 114 and AlN formed on the first electron blocking layer 131. A second electron blocking layer 132 and a third electron blocking layer 133 including GaN formed on the second electron blocking layer 132 may be included.

According to the exemplary embodiment, the first electron blocking layer 131 having the first energy bandgap Eg1 below the energy bandgap Egw of the quantum well is formed on the active layer 114 to lower the energy level, thereby overloading electrons. By preventing the flow and increasing the relative energy barrier with the second electron blocking layer 132 to be formed later, the overflow of the electrons can be prevented to effectively prevent the leakage of electrons.

For example, the first electron blocking layer 131 may include InN, and as the InN is formed on the active layer 114, the energy level is lowered to prevent the electrons from overflowing and the electrons formed thereafter. By increasing the relative energy barrier with the blocking layer, the electrons can be prevented from overflowing, which effectively blocks the leakage of electrons.

In addition, according to the embodiment, the second electron blocking layer 132 having a second energy band gap Eg2 or more than the energy band gap Egb of the quantum wall is formed on the first electron blocking layer 131 to form an electron. Leakage can be shut off.

For example, the second electron blocking layer 132 includes AlN to form a second electron blocking layer 132 having a second energy bandgap Eg2 greater than or equal to the energy bandgap Egb of the quantum wall. The leakage of electrons can be blocked. When the second electron blocking layer 132 includes AlN, an energy barrier is increased compared to the electron blocking layer employing AlGaN, thereby more effectively blocking the overflow of electrons.

In addition, the embodiment may form a third electron blocking layer 133 including GaN on the second electron blocking layer 132, the third electron blocking layer 133 is p-doped p May include -GaN. The third electron blocking layer 133 may be less than or equal to the second energy band gap Eg2 and may have a third energy band gap Eg3 greater than or equal to the energy band gap Egb of the quantum wall.

For example, the third electron blocking layer 133 may efficiently block electrons that overflow due to ion implantation in a concentration range of about 10 ¹⁸ to 10 ²⁰ / cm ³ and increase the injection efficiency of the hole.

Accordingly, the third electron blocking layer 133 may block the leakage of electrons and efficiently inject holes from the hole injection layer into the active layer.

In example embodiments, the electron blocking layer 130 may include InN / AlN / p-GaN, and AlN / p-GaN may be formed in a plurality of cycles. The formation process of AlN / p-GaN in the embodiment will be described later.

According to the embodiment, InN / AlN / p-GaN is used to make low energy into the InN layer, block electron overflow through the AlN layer, and inject holes into the active layer through the p-GaN layer to recombine the active layer ( It can promote the recombination and contribute to increase the light efficiency.

Accordingly, according to the light emitting device according to the embodiment, the hole injection efficiency is excellent and at the same time it can effectively block the leakage of electrons.

In addition, the embodiment may form a fourth electron blocking layer 134 including AlN on the third electron blocking layer 133, and include p-GaN on the fourth electron blocking layer 134. The fifth electron blocking layer 135 may be formed.

In an embodiment, AlN of the fourth electron blocking layer 134 may be thinner than AlN of the second electron blocking layer 132, and p-GaN of the fifth electron blocking layer 135 is the third electron blocking layer. It may be thicker than the p-GaN of layer 133.

Accordingly, according to the embodiment, the second electron blocking layer 132, which is a relatively thick AlN layer for electrons overflowing from the active layer, functions as an energy barrier, and the p-GaN is relatively thick for holes injected from the hole injection layer. The hole may be injected in the fifth electron blocking layer 135, which is a layer.

That is, according to the embodiment, the thickness of the electron blocking layer of AlN adjacent to the active layer may be thicker than the electron blocking layer of AlN adjacent to the second conductive semiconductor layer 116 which is a hole injection layer.

In addition, according to the embodiment, the thickness of the p-GaN electron blocking layer adjacent to the second conductive semiconductor layer 116 as the hole injection layer may be thicker than that of the p-GaN electron blocking layer adjacent to the active layer 114.

Accordingly, the AlN barrier layer adjacent to the active layer 114 can effectively block electrons overflowing from the active layer, and the p-GaN electron barrier layer adjacent to the second conductive semiconductor layer 116 is a hole injection layer. The hole injected from the conductive semiconductor layer 116 may be efficiently injected into the active layer.

In addition, the embodiment may form a sixth electron blocking layer 136 including AlN on the fifth electron blocking layer 135, and include p-GaN on the sixth electron blocking layer 136. The seventh electron blocking layer 137 may be formed.

In an embodiment, AlN of the sixth electron blocking layer 136 may be thinner than AlN of the fourth electron blocking layer 134, and p-GaN of the seventh electron blocking layer 137 may be the fifth electron blocking layer. It may be thicker than the p-GaN of layer 135.

Accordingly, the AlN barrier layer adjacent to the active layer 114 can effectively block electrons overflowing from the active layer, and the p-GaN electron barrier layer adjacent to the second conductive semiconductor layer 116 is a hole injection layer. The hole injected from the conductive semiconductor layer 116 may be efficiently injected into the active layer.

According to the light emitting device, the method of manufacturing the light emitting device, the light emitting device package, and the lighting system according to the embodiment, the hole injection efficiency is excellent and at the same time it is possible to effectively block the leakage of electrons.

3 is an exemplary timing diagram for forming an electron blocking layer of a light emitting device according to an embodiment.

First, a step of forming a first electron blocking layer 131 including InN on the active layer 114 is performed.

For example, the InN first electron blocking layer 131 may be formed by injecting the In source and the N source during the time period T1. For example, the In source may be trimethyl indium gas (TMIn), and the N source may be ammonia gas (NH ₃ ) or dimethylhydrazine (DMHy), but is not limited thereto.

Next, a second electron blocking layer 132 including AlN is formed on the first electron blocking layer 131.

In the forming of the second electron blocking layer 132 including AlN in an embodiment, in order to increase the crystallinity of the AlN layer, the pulse mode is a method of alternately turning on and off the N source and the Al source during the growth of the AlN layer. It can be implemented in (pulse mode).

For example, after stopping the injection of the In source and the N source for T2 time, only the Al source is supplied for the T3 time, and only the N source for the T4 time can be formed to form a high quality AlN layer. The Al source may use trimethyl aluminum (TMAl), and the N source may be ammonia gas (NH ₃ ) or dimethylhydrazine (DMHy), but is not limited thereto.

Next, a third electron blocking layer 133 including GaN is formed on the second electron blocking layer 132. The third electron blocking layer 133 may include p-GaN doped with a P-type.

For example, an Al source and an N source may be stopped for a T5 time, and an N source, a Ga source, and a P-type dopant may be supplied for a T6 time to form a p-GaN layer. The Ga source may be trimethylgallium (TMGa) or triethylgallium (TEGa), but is not limited thereto. The P-type dopant may be Mg or Zn, when the dopant is Mg, Cp2Mg gas may be used, and when the dopant is Zn, DMZn may be used, but is not limited thereto.

Accordingly, the electron blocking layer 130 may include InN / AlN / p-GaN, and AlN / p-GaN may be formed in a plurality of cycles.

For example, after the process of forming the third electron blocking layer 133, the fourth electron blocking layer 134, the fifth electron blocking layer 135, the sixth electron blocking layer 136, and the seventh electron blocking layer 137. This can be formed sequentially.

For example, a fourth electron blocking layer 134 including AlN is formed on the third electron blocking layer 133.

For example, after stopping the Ga source, the N source and the P-type dopant implantation for T7 hours, only the Al source is supplied for T8 hours and only the N source for T9 hours to form a high quality AlN layer. .

In this case, the fourth electron blocking layer 134 of AlN may be thinner than the second electron blocking layer 132 of AlN. Accordingly, the times T7 and T8 for forming the fourth electron blocking layer 134 may be shorter than the times T3 and T4 for forming the second electron blocking layer 132.

Next, a fifth electron blocking layer 135 including GaN is formed on the fourth electron blocking layer 134. The fifth electron blocking layer 135 may include p-GaN doped with a P-type.

For example, the Al source and the N source may be stopped for T10 time, and the N source, Ga source, and P type dopant may be supplied for the T11 time to form a p-GaN layer.

In this case, the fifth electron blocking layer 135 of p-GaN may be thicker than the third electron blocking layer 133 of p-GaN. Accordingly, the time T11 for forming the fifth electron blocking layer 135 may be longer than the time T6 for forming the third electron blocking layer 133.

Thereafter, a sixth electron blocking layer 136 including AlN is formed on the fifth electron blocking layer 135 in a pulse mode, and the p-GaN seventh electron blocking layer is formed on the sixth electron blocking layer 136. Layer 137 may be formed.

The sixth electron blocking layer 136 of AlN may be thinner than the fourth electron blocking layer 134 of AlN, and the seventh electron blocking layer 137 of p-GaN may be formed of the p-GaN material. 5 may be thicker than the electron blocking layer 135.

According to the embodiment, the AlN barrier layer adjacent to the active layer 114 can effectively block electrons overflowing from the active layer, and the p-GaN electron barrier layer adjacent to the second conductive semiconductor layer 116 is a hole injection layer. The hole injected from the second conductive semiconductor layer 116 may be efficiently injected into the active layer.

According to the light emitting device, the method of manufacturing the light emitting device, the light emitting device package, and the lighting system according to the embodiment, the hole injection efficiency is excellent and at the same time it is possible to effectively block the leakage of electrons.

4 illustrates a structure of a light emitting device 100 according to an embodiment.

The embodiment has been described based on a vertical light emitting device, but this is only an example, and may be applied to a horizontal light emitting device, a flip chip light emitting device, a hybrid light emitting device including a via hole, and the like.

The light emitting device according to the embodiment includes a light emitting structure 110 including a first conductive semiconductor layer 112, an active layer 114, and a second conductive semiconductor layer 116, and a portion of an upper surface of the light emitting structure 110. The passivation layer 140 may include the first electrode 150 formed on the light emitting structure 110.

An embodiment may include an electron blocking layer 130 between the active layer 114 and the second conductive semiconductor layer 116.

For example, the electron blocking layer 130 includes a first electron blocking layer 131 including InN formed on the active layer 114 and AlN formed on the first electron blocking layer 131. A second electron blocking layer 132 and a third electron blocking layer 133 including GaN formed on the second electron blocking layer 132 may be included.

According to the exemplary embodiment, the first electron blocking layer 131 having the first energy bandgap Eg1 below the energy bandgap Egw of the quantum well is formed on the active layer 114 to lower the energy level, thereby overloading electrons. By preventing the flow and increasing the relative energy barrier with the second electron blocking layer 132 to be formed later, the overflow of the electrons can be prevented to effectively prevent the leakage of electrons.

In addition, according to the embodiment, the thickness of the electron blocking layer of AlN adjacent to the active layer 114 may be thicker than that of the AlN electron blocking layer adjacent to the second conductive semiconductor layer 116, which is a hole injection layer. The thickness of the p-GaN electron blocking layer adjacent to the second conductive semiconductor layer 116 may be thicker than that of the p-GaN electron blocking layer adjacent to the active layer 114.

Accordingly, in some embodiments, the AlN barrier layer adjacent to the active layer 114 can effectively block electrons overflowing from the active layer, and the p-GaN electron barrier layer adjacent to the second conductive semiconductor layer 116 can be hole injected. The hole injected from the second conductive semiconductor layer 116, which is a layer, may be efficiently injected into the active layer.

In an embodiment, the composition formula of the first conductive semiconductor layer 112 may be _{In x Al y Ga 1 -x- y} N (0≤x≤1, 0≤y≤1, 0≤x + y≤1) It may include a semiconductor material having. For example, the first conductive semiconductor layer 112 may be formed of any one or more of GaN, InN, AlN, InGaN, AlGaN, InAlGaN, AlInN, AlGaAs, InGaAs, AlInGaAs, GaP, AlGaP, InGaP, AlInGaP, InP. Can be.

The active layer 114 may be formed of at least one of a single quantum well structure, a multi quantum well structure (MQW), a quantum-wire structure, or a quantum dot structure.

The well layer 114w / barrier layer 114b of the active layer 114 may be any one of InGaN / GaN, InGaN / InGaN, GaN / AlGaN, InAlGaN / GaN, GaAs (InGaAs) / AlGaAs, GaP (InGaP) / AlGaP. The pair structure may be formed, but is not limited thereto. The well layer may be formed of a material having a band gap lower than the band gap of the barrier layer.

The second conductivity-type semiconductor layer 116 is a compound semiconductor of a Group III-V group element doped with a second conductivity type dopant, for example, In _x Al _y Ga _{1 -x- y} N (0 _{≦ x ≦} 1, 0 It may include a semiconductor material having a composition formula of ≤ y ≤ 1, 0 ≤ x + y ≤ 1). The second conductive semiconductor layer 116 may be selected from, for example, GaN, AlN, AlGaN, InGaN, InN, InAlGaN, AlInN, AlGaAs, GaP, GaAs, GaAsP, AlGaInP, or the like.

In an exemplary embodiment, the first conductive semiconductor layer 112 may be an N-type semiconductor layer, and the second conductive semiconductor layer 116 may be a P-type semiconductor layer, but is not limited thereto. In addition, an N-type semiconductor layer (not shown) is formed on the second conductive semiconductor layer 116 when a semiconductor having a polarity opposite to that of the second conductive type, for example, the second conductive semiconductor layer 116 is a P-type semiconductor layer. C) can be further formed. Accordingly, the light emitting structure 110 may be implemented as 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.

Concave-convex (R) is formed on the upper surface of the light emitting structure 110 to increase the light extraction efficiency.

A second electrode layer 120 is formed below the light emitting structure 110, and the second electrode layer 120 includes an ohmic layer 122, a reflective layer 124, a bonding layer 125, and a support substrate 126. It may include.

For example, the ohmic layer 122 may include indium tin oxide (ITO), indium zinc oxide (IZO), indium zinc tin oxide (IZTO), indium aluminum zinc oxide (IAZO), indium gallium zinc oxide (IGZO), and IGTO. (indium gallium tin oxide), AZO (aluminum zinc oxide), ATO (antimony tin oxide), GZO (gallium zinc oxide), IZON (IZO Nitride), AGZO (Al-Ga ZnO), IGZO (In-Ga ZnO), ZnO, IrOx, RuOx, NiO, RuOx / ITO, Ni / IrOx / Au, and Ni / IrOx / Au / ITO, Ag, Ni, Cr, Ti, Al, Rh, Pd, Ir, Ru, Mg, Zn, Pt At least one of Au, Hf, and the like may be formed, and the material is not limited thereto.

In addition, the reflective layer 124 may be formed of a metal or an alloy including at least one of Ag, Ni, Al, Rh, Pd, Ir, Ru, Mg, Zn, Pt, Au, and Hf. In addition, the reflective layer 124 may be formed in a multilayer using a light transmitting conductive material such as IZO, IZTO, IAZO, IGZO, IGTO, AZO, ATO, and the like, for example, IZO / Ni, AZO. / Ag, IZO / Ag / Ni, AZO / Ag / Ni and the like can be laminated.

In addition, the bonding layer 125 may include at least one of Ti, Au, Sn, Ni, Cr, Ga, In, Bi, Cu, Ag, or Ta.

In addition, the conductive support substrate 126 may include copper (Cu), copper alloy (Cu Alloy), gold (Au), nickel (Ni), molybdenum (Mo), copper-tungsten (Cu-W), and a carrier wafer (eg For example, it may include at least one of Si, Ge, GaAs, GaN, ZnO, SiGe, SiC and the like.

A protection member 190 may be formed on the lower outer side of the light emitting structure 110, and a current blocking layer CBL 129 is formed between the light emitting structure 110 and the ohmic layer 122. Can be formed.

The protection member 190 may be formed in a circumferential region between the light emitting structure 110 and the bonding layer 125, and may be formed in a ring shape, a loop shape, a square frame shape, or the like. A portion of the protection member 190 may overlap the light emitting structure 110 in a vertical direction.

The protection member 190 may reduce the possibility of occurrence of an electrical short between the bonding layer 125 and the active layer 114 by increasing the distance between the side of the bonding layer 125 and the active layer 114, Electrical short circuits can be prevented from occurring during the chip separation process.

The protection member 140 is a material having electrical insulation, a material having lower electrical conductivity than the reflective layer 124 or the bonding layer 1125, or a material forming Schottky contact with the second conductive semiconductor layer 116. It can be formed using. For example, the protective member 140 may include ITO, IZO, IZTO, IAZO, IGZO, IGTO, AZO, ATO, ZnO, SiO ₂ , SiO _x , SiO _x N _y , Si ₃ N ₄ , Al ₂ O ₃ , TiO It may include at least one of _x , TiO ₂ , Ti, Al or Cr.

According to the light emitting device, the method of manufacturing the light emitting device, the light emitting device package, and the lighting system according to the embodiment, it is possible to realize a light emitting device having high hole injection efficiency while effectively blocking electron leakage.

5 is a view illustrating a light emitting device package 200 having a light emitting device according to embodiments.

The light emitting device package according to the embodiment is provided in the package body portion 205, the third electrode layer 213 and the fourth electrode layer 214 provided on the package body portion 205, and the package body portion 205. The light emitting device 100 is electrically connected to the third electrode layer 213 and the fourth electrode layer 214, and a molding member 240 surrounding the light emitting device 100 is included.

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

The third electrode layer 213 and the fourth electrode layer 214 are electrically isolated from each other and provide power to the light emitting device 100. The third electrode layer 213 and the fourth electrode layer 214 may function to increase light efficiency by reflecting the light generated from the light emitting device 100, And may serve to discharge heat to the outside.

The light emitting device 100 may be a vertical type light emitting device, but is not limited thereto. A horizontal type light emitting device may also be applied.

The light emitting device 100 may be installed on the package body 205 or on the third electrode layer 213 or the fourth electrode layer 214.

The light emitting device 100 may be electrically connected to the third electrode layer 213 and / or the fourth electrode layer 214 by a wire, flip chip, or die bonding method. The light emitting device 100 is electrically connected to the third electrode layer 213 through the wire 230 and is electrically connected to the fourth electrode layer 214 directly.

The molding member 240 may surround the light emitting device 100 to protect the light emitting device 100. In addition, the molding member 240 may include a phosphor to change the wavelength of the light emitted from the light emitting device 100.

A plurality of light emitting device packages according to the embodiment may be arranged on a substrate, and a light guide plate, a prism sheet, a diffusion sheet, a fluorescent sheet, or the like, which is an optical member, may be disposed on a path of light emitted from the light emitting device package. The light emitting device package, the substrate, and the optical member may function as a backlight unit or function as a lighting unit. For example, the lighting system may include a backlight unit, a lighting unit, a pointing device, a lamp, and a streetlight.

6 is a perspective view 1100 of a lighting unit according to an embodiment. However, the lighting unit 1100 of FIG. 6 is an example of a lighting system, but is not limited thereto.

In the embodiment, the lighting unit 1100 is connected to the case body 1110, the light emitting module unit 1130 installed on the case body 1110, and the case body 1110 and receive power from an external power source. It may include a terminal 1120.

The case body 1110 may be formed of a material having good heat dissipation characteristics. For example, the case body 1110 may be formed of a metal material or a resin material.

The light emitting module unit 1130 may include a substrate 1132 and at least one light emitting device package 200 mounted on the substrate 1132.

The substrate 1132 may be a circuit pattern printed on an insulator, and for example, a general printed circuit board (PCB), a metal core PCB, a flexible PCB, a ceramic PCB, and the like. It may include.

In addition, the substrate 1132 may be formed of a material that reflects light efficiently, or the surface may be formed of a color that reflects light efficiently, for example, white, silver, or the like.

The at least one light emitting device package 200 may be mounted on the substrate 1132. Each of the light emitting device packages 200 may include at least one light emitting diode (LED) 100. The light emitting diodes 100 may include colored light emitting diodes emitting red, green, blue, or white colored light, and UV light emitting diodes emitting ultraviolet (UV) light.

The light emitting module unit 1130 may be disposed to have a combination of various light emitting device packages 200 to obtain color and luminance. For example, a white light emitting diode, a red light emitting diode, and a green light emitting diode may be combined to secure high color rendering (CRI).

The connection terminal 1120 may be electrically connected to the light emitting module unit 1130 to supply power. In an embodiment, the connection terminal 1120 is coupled to the external power source by a socket, but is not limited thereto. For example, the connection terminal 1120 may be formed in a pin shape and inserted into an external power source, or may be connected to the external power source by a wire.

7 is an exploded perspective view 1200 of a backlight unit according to an embodiment. However, the backlight unit 1200 of FIG. 7 is an example of an illumination system, but is not limited thereto.

The backlight unit 1200 according to the embodiment includes a light guide plate 1210, a light emitting module unit 1240 that provides light to the light guide plate 1210, a reflective member 1220 under the light guide plate 1210, and the light guide plate. 1210, a bottom cover 1230 for accommodating the light emitting module unit 1240 and the reflective member 1220, but is not limited thereto.

The light guide plate 1210 serves to surface light by diffusing light. The light guide plate 1210 is made of a transparent material, for example, an acrylic resin series such as polymethyl metaacrylate (PMMA), polyethylene terephthlate (PET), polycarbonate (PC), cycloolefin copolymer (COC), and polyethylene naphthalate (PEN). It may include one of the resins.

The light emitting module unit 1240 provides light to at least one side of the light guide plate 1210 and ultimately serves as a light source of a display device in which the backlight unit is installed.

The light emitting module unit 1240 may be in contact with the light guide plate 1210, but is not limited thereto. Specifically, the light emitting module 1240 includes a substrate 1242 and a plurality of light emitting device packages 200 mounted on the substrate 1242. The substrate 1242 is mounted on the light guide plate 1210, But is not limited to.

The substrate 1242 may be a printed circuit board (PCB) including a circuit pattern (not shown). However, the substrate 1242 may include not only a general PCB, but also a metal core PCB (MCPCB), a flexible PCB (FPCB), and the like.

The plurality of light emitting device packages 200 may be mounted on the substrate 1242 such that a light emitting surface on which light is emitted is spaced apart from the light guide plate 1210 by a predetermined distance.

The reflective member 1220 may be formed under the light guide plate 1210. The reflection member 1220 reflects the light incident on the lower surface of the light guide plate 1210 so as to face upward, thereby improving the brightness of the backlight unit. The reflective member 1220 may be formed of, for example, PET, PC, or PVC resin, but is not limited thereto.

The bottom cover 1230 may accommodate the light guide plate 1210, the light emitting module unit 1240, the reflective member 1220, and the like. For this purpose, the bottom cover 1230 may be formed in a box shape having an opened upper surface, but the present invention is not limited thereto.

The bottom cover 1230 may be formed of a metal material or a resin material, and may be manufactured using a process such as press molding or extrusion molding.

According to the embodiment, a high output light emitting device, a manufacturing method of the light emitting device, a light emitting device package, and an illumination system can be provided.

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 each embodiment may be combined or modified with respect to other embodiments by those 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.

Claims (12)

A first conductive semiconductor layer;
An active layer formed on the first conductivity type semiconductor layer including a quantum well and a quantum wall;
An electron blocking layer on the active layer;
And a second conductivity type semiconductor layer on the electron blocking layer.
The electron blocking layer,
A first electron blocking layer including InN on the active layer;
A second electron blocking layer including AlN on the first electron blocking layer; And
And a third electron blocking layer including GaN on the second electron blocking layer. The method according to claim 1,
The third electron blocking layer is a p-GaN doped light emitting device. The method according to claim 1,
A fourth electron blocking layer including AlN on the third electron blocking layer; And
And a fifth electron blocking layer including GaN on the fourth electron blocking layer. The method of claim 3,
The thickness of the fourth electron blocking layer is thinner than the thickness of the second electron blocking layer,
The thickness of the fifth electron blocking layer is thicker than the thickness of the third electron blocking layer. The method according to claim 1,
The first electron blocking layer is
A light emitting device having a first energy band gap of less than or equal to the energy band gap of the quantum well. 6. The method of claim 5,
The second electron blocking layer,
Has a second energy bandgap above the energy bandgap of the quantum wall,
The third electron blocking layer has a third energy bandgap less than or equal to the second energy bandgap and greater than or equal to the energy bandgap of the quantum wall. A first conductive semiconductor layer;
An active layer formed on the first conductivity type semiconductor layer including a quantum well and a quantum wall;
An electron blocking layer on the active layer;
And a second conductivity type semiconductor layer on the electron blocking layer.
The electron blocking layer,
An InN electron blocking layer on the active layer;
At least one AlN electron blocking layer on the InN electron blocking layer; And
And at least one GaN electron blocking layer on the AlN electron blocking layer. The method of claim 7, wherein
The thickness of the AlN electron blocking layer adjacent to the active layer is thicker than the AlN electron blocking layer adjacent to the second conductivity type semiconductor layer. The method of claim 8,
The GaN electron blocking layer adjacent to the second conductive semiconductor layer is thicker than the GaN electron blocking layer adjacent to the active layer. The method of claim 7, wherein
The GaN electron blocking layer is p-GaN doped with a p-type light emitting device. The method of claim 7, wherein
The InN electron blocking layer,
A light emitting device having a first energy band gap of less than or equal to the energy band gap of the quantum well. 12. The method of claim 11,
The AlN electron blocking layer is
Has a second energy bandgap above the energy bandgap of the quantum wall,
The GaN electron blocking layer has a third energy bandgap less than or equal to the second energy bandgap and greater than or equal to the energy bandgap of the quantum wall.

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