KR20160114867A - Red light emitting device and lighting system - Google Patents

Abstract

An embodiment of the present invention relates to a red light emitting device, a method for manufacturing a light emitting device, a light emitting device package, and a lighting system. According to the embodiment of the present invention, the red light emitting device may comprise: a first conductive-type first semiconductor layer (112); an active layer (114) formed on the first conductive-type first semiconductor layer (112); a second conductive-type second semiconductor layer (116) formed on the active layer (114); a second conductive-type fourth semiconductor layer (124) formed on the second conductive-type second semiconductor layer (116); and a second conductive-type fifth semiconductor layer (125) formed on the second conductive-type fourth semiconductor layer (124). A doping concentration of a second conductive-type element of the second conductive-type fourth semiconductor layer (124) may be lower than a doping concentration of a second conductive-type element of the second conductive-type fifth semiconductor layer (125). The present invention provides the red light emitting device which has high light output performance.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a red light emitting device,

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

A light emitting diode (LED) is a pn junction diode in which electrical energy is converted into light energy. The dopant of the semiconductor compound can be generated by combining the semiconductor compound on the periodic table. By adjusting the composition ratio of the semiconductor compound, A light emitting element, a green light emitting element, an ultraviolet (UV) light emitting element, or a red (RED) light emitting element.

For example, there is an AlGaInP-based light emitting diode as a red light emitting element, which can convert the injected electric energy into light having a wavelength within a range of about 570 nm to about 630 nm. The wavelength change depends on the band gap energy level of the light emitting diode. The band gap size can be controlled by changing the composition ratio of Al and Ga, and the wavelength can be shortened as the composition ratio of Al is increased.

Recently, the AlGaInP red LED has been applied to a high CRI (Color Rendering Index) illumination light source or vehicle light source, and market competition is intensifying. Therefore, securing high light output or electrical reliability is an important issue .

For example, according to the conventional art, the doping element of the carrier diffuses into the active region according to the current injection, causing the light flux to drop.

Also, according to the related art, there is a problem that the operating voltage Vf increases as the current is injected.

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

Also, the embodiments are directed to a red light emitting device having high electrical reliability, a method of manufacturing a light emitting device, a light emitting device package, and an illumination system.

The red light emitting device includes a first conductive type first semiconductor layer 112; An active layer 114 on the first conductive type first semiconductor layer 112; A second conductive type second semiconductor layer 116 on the active layer 114; A second conductive type fourth semiconductor layer (124) on the second conductive type second semiconductor layer (116); And a second conductive type fifth semiconductor layer 125 on the second conductive type fourth semiconductor layer 124.

The doping concentration of the second conductive type semiconductor layer 125 of the second conductive type fourth semiconductor layer 124 may be lower than the doping concentration of the second conductive type element of the second conductive type fifth semiconductor layer 125.

The illumination system according to the embodiment may include a light emitting unit having the red light emitting element.

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

Also, the embodiments can provide a red light emitting device having high electrical reliability, a method of manufacturing a light emitting device, a light emitting device package, and an illumination system.

1 is a sectional view of a red light emitting device according to a first embodiment;
2 is a SIMS data of a red light emitting device according to an embodiment.
FIGS. 3A and 3B are data on the rate of change of light flux during operation / life test of the comparative example and the embodiment, respectively.
4 is a graph showing the operating voltage data of the red light emitting device according to the comparative example and the example.
5 is a graph showing luminous flux data of a red light emitting device according to Comparative Examples and Examples.
6 is a cross-sectional view of a red light emitting device according to a second embodiment;
7A and 7B show operating voltage data of the red light emitting device according to the comparative example and the example.
8 is a partially enlarged view of a red light emitting element according to the second embodiment.
9 to 11 are process sectional views of a method of manufacturing a red light emitting device according to an embodiment.
13 is a sectional view of a red light emitting device according to the third embodiment.
13 is a cross-sectional view of a light emitting device package according to an embodiment.
14 is a sectional view of a lighting device according to an embodiment.

In the description of the embodiments, it is to be understood that each layer (film), region, pattern or structure is "on" or "under" a substrate, each layer, region, pad or pattern Quot; upper "and" lower "include those formed through" directly "or" through another layer ". In addition, the criteria for the top, bottom, or bottom of each layer will be described with reference to the drawings.

(Example)

1 is a cross-sectional view of a red light emitting device 100 according to the first embodiment.

The red light emitting device 100 according to the first embodiment includes a first conductive type first semiconductor layer 112, an active layer 114, a second conductive type second semiconductor layer 116, a second conductive type fourth semiconductor layer 112, A second conductive type semiconductor layer 124, and a second conductive type fifth semiconductor layer 125.

For example, the red light emitting device 100 according to the first embodiment includes a first conductive type first semiconductor layer 112, an active layer 114 on the first conductive type first semiconductor layer 112, A second conductive type second semiconductor layer 116 on the active layer 114 and a second conductive type fourth semiconductor layer 124 on the second conductive type second semiconductor layer 116, Type fifth semiconductor layer 125 may be formed on the fourth semiconductor layer 124 of the second conductivity type.

The second conductive type fourth semiconductor layer 124 may include a p-type GaP layer of a first concentration and the fifth semiconductor layer 125 may include a p-type GaP layer of a second concentration .

1 will be described in the following manufacturing method.

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

2 is SIMS data of a red light emitting device according to an embodiment.

The doping concentration of the second conductive type element of the second conductive type fourth semiconductor layer 124 may be lower than the doping concentration of the second conductive type element of the second conductive type fifth semiconductor layer 125 .

For example, in the embodiment, the doping concentration of Mg, which is the second conductive type element of the second conductive type fourth semiconductor layer 124, is the second conductive type element of the fifth conductive type semiconductor layer 125 May be lower than the doping concentration of Mg.

For example, the second conductive type fourth semiconductor layer 124 is a GaP layer, a p-type dopant is Mg, and can be doped, the composition (concentration) is ^{1X10 16 ~ 5X10 17 (atoms /} cm -3) Lt; / RTI >

For example, the second conductive type fifth semiconductor layer 125 may be a GaP layer, may be doped with Mg as a p-type dopant, and may have a concentration of 5 × 10 ¹⁶ to 1 × ^{10 18} atoms / cm ^-3 have.

The doping concentration of the second conductive type semiconductor layer of the second conductive type fourth semiconductor layer 124 may be lower than the doping concentration of the second conductive type semiconductor layer 122 of the second conductive type semiconductor layer 122.

For example, the Mg doping concentration, which is the second conductive type element of the second conductive type fourth semiconductor layer 124, is higher than the doping concentration of Mg, which is the second conductive type element of the second conductive type second semiconductor layer 122 ≪ / RTI >

For example, the second conductive type second semiconductor layer 122 may be an AlGaInP layer, which may be doped with Mg as a p-type dopant, and may have a concentration of 5 × 10 ¹⁶ to 1 × ^{10 18} atoms / cm ^-3 have.

According to the prior art, the dopant of the second conductive type fifth semiconductor layer 125, for example, Mg is diffused into the active layer region according to the current injection during the LED lifetime test, .

In order to prevent the light flux from dropping due to the diffusion of the dopant of the second conductive type fifth semiconductor layer 125, the doping concentration of Mg, which is the second conductive type element of the fifth conductive type semiconductor layer 125 of the second conductive type, The second conductive type fourth semiconductor layer 124 is interposed between the second conductive type fifth semiconductor layer 125 and the second conductive type second semiconductor layer 122 to diffuse the dopant, By trapping Mg, the diffusion of the dopant is cut off, so that the light flux does not fall and the initial value is maintained.

FIGS. 3A and 3B are light flux change rate data at the time of operation / life test of the comparative example and the embodiment, respectively. 1 to 9 means the sample number tested.

In the comparative example, as shown in FIG. 3A, the light flux deviates from the predetermined tolerance range (± 10%) according to the current injection (X axis) during the LED life test.

On the other hand, in the experimental example, as shown in FIG. 3B, the luminous flux was maintained without deviating from the predetermined tolerance range (± 10%) according to the current injection (X axis) during the LED life test.

The thickness of the second conductive type fourth semiconductor layer 124 may be smaller than the thickness of the second conductive type fifth semiconductor layer 125 in the embodiment. For example, the thickness of the second conductive type fourth semiconductor layer 124 may be about 1500 Å to 5000 Å, and the thickness of the second conductive type fifth semiconductor layer 125 may be about 20,000 Å to 50,000 Å .

FIG. 4 is operating voltage data of the red light emitting device according to the comparative example and the embodiment, and FIG. 5 is luminous flux data of the red light emitting device according to the comparative example and the embodiment.

The thickness of the second conductive type fifth semiconductor layer 125 may be greater than the thickness of the second conductive type second semiconductor layer 122 in the embodiment.

For example, the thickness of the second conductive type fifth semiconductor layer 125 may be about 10 times greater than the thickness of the second conductive type second semiconductor layer 122. This improves the reliability of the red light emitting device according to the embodiment, and the light flux can be improved.

For example, the thickness of the second conductive type fifth semiconductor layer 125 may be 8,000 to 140,000, and the thickness of the second conductive type second semiconductor layer 122 may be 2,000 to 6,000. have.

As shown in FIGS. 4 and 5, according to the embodiment, when the thickness of the second conductive type fifth semiconductor layer 125 serving as a current spreading and window in the chip is greater than the thickness of the second conductive type The operation voltage Vf and the luminous flux can be improved by 10 times or more as compared with the second semiconductor layer 122.

A DBR (Distributed Bragg-Reflector) may be provided between the substrate 105 and the active layer 114 as the semiconductor reflection layer 107 in order to direct the light emission distribution upward in the light emitting device.

For example, as shown in FIG. 1, the semiconductor reflection layer 107 of the embodiment is formed by stacking one or more pairs of a first refraction layer having a first refraction index and a second refraction layer having a second refraction index larger than the first refraction index alternately And a lattice layer.

The semiconductor reflection layer 107 may include an AlAs layer (not shown) / an AlGaAs layer (not shown), and the semiconductor reflection layer 107 may be doped with a first conductive dopant.

The composition of Al in the AlAs layer may be higher than the composition of Al in the AlGaAs layer, and the semiconductor reflection layer 107 having such a structure can effectively reflect light in a red range wavelength.

6 is a cross-sectional view of a red light emitting device 102 according to the second embodiment.

The second embodiment can employ the technical features of the first embodiment, and will be described below mainly on the main features of the second embodiment.

The second embodiment may further include a second conductive type third semiconductor layer 123 between the active layer 114 and the second conductive type second semiconductor layer 122.

The second conductive type third semiconductor layer 123 may include an (Al _x Ga _{1 -x} ) InP layer (0 _{? X} ? 1).

The composition of Al in the second conductive type third semiconductor layer 123 may vary.

For example, the composition of Al in the second conductive type third semiconductor layer 123 may gradually increase from the active layer 114 toward the second conductive type fifth semiconductor layer 125.

7A and 7B are operating voltage data of the red light emitting device according to the comparative example and the embodiment.

The second conductive type third semiconductor layer 123 is formed between the active layer 114 and the second conductive type second semiconductor layer 122 so that the composition of Al gradually changes, (Eg) buffer layer can be formed.

As shown in FIG. 7A, in the comparative example, when the Eg buffer layer is not present, that is, when the second conductive type third semiconductor layer 123 is absent, Vf increases as the current is injected during the reliability life test .

On the other hand, when the second conductive type third semiconductor layer 123, which is an Eg buffer layer, exists between the active layer 114 and the second conductive type second semiconductor layer 122 as shown in FIG. 7B, The rate of change remained very stable.

8 is a partial enlarged view of the fifth conductive type semiconductor layer 125 of the red light emitting device according to the second embodiment.

The second conductive type fifth semiconductor layer 125 may include a superlattice structure of a GaP layer 125a / In _x Ga _1-x P layer (where 0 _{? X?} 1) 125b have.

The second conductive type fifth semiconductor layer 125 may include a third GaP layer 125c doped with a second conductive dopant. The second conductive dopant may be a p-type conductive dopant, but is not limited thereto.

The second conductivity type fifth semiconductor layer 125 may be doped with a second conductivity type dopant and the second conductivity type dopant having a concentration lower than the first concentration may be doped in the GaP layer 125a. . The In _x Ga _1-x P layer (where 0 _{? X?} 1) 125b may not be doped with the second conductivity type dopant.

For example, the second conductivity type fifth semiconductor layer 125 has a Mg of about 10X10 ¹⁸ concentration may be doped, GaP layer (125a) has may be Mg-doped of 10X10 ¹⁷ concentration, the In _x Ga _{1 -x} P layer (where 0? x? 1) 125b may not be doped with the second conductive type dopant, but the present invention is not limited thereto.

Accordingly, the second conductive type fifth semiconductor layer 125 may have a superlattice structure of a GaP layer 125a / In _x Ga _1-x P layer (0 _{? X?} 1) 125b And the In _x Ga _1-x P layer (where 0 _{? X?} 1) 125b has a low energy level and the GaP layer 125a is an In _x Ga _1-x P layer 1) (125b).

Hereinafter, a method of manufacturing a red light emitting device according to an embodiment will be described with reference to FIGS. 9 to 11. FIG. The following description is based on the drawing of the second embodiment, but the embodiment is not limited thereto.

First, a substrate 105 is prepared as shown in FIG. The substrate 105 may be formed of a material having excellent thermal conductivity, and may be a conductive substrate or an insulating substrate. For example, the substrate 105 may use at least one of GaAs, sapphire (Al ₂ O ₃ ), SiC, Si, GaN, ZnO, GaP, InP, Ge and Ga ₂ O ₃ . The concavoconvex structure P may be formed on the substrate 105, but the present invention is not limited thereto. The substrate 105 may be wet-cleaned to remove impurities on the surface.

A buffer layer may be formed on the substrate 105. The buffer layer may alleviate the lattice mismatch between the material of the light emitting structure 110 and the substrate 105 and the material of the buffer layer may be a Group III-V compound semiconductor such as GaN, InN, AlN, InGaN, AlGaN, InAlGaN , And AlInN.

Thereafter, the semiconductor reflection layer 107 may be formed on the substrate 105 or the buffer layer.

The semiconductor reflection layer 107 may form a super lattice layer by laminating one or more pairs of a first refraction layer having a first refraction index and a second refraction layer having a second refraction index larger than the first refraction index alternately.

The semiconductor reflection layer 107 may be formed in situ by MOCVD together with the light emitting structure 110 to be formed thereafter, but is not limited thereto.

In the embodiment, the reflection effect of the semiconductor reflection layer 107 is caused by the constructive interference of the optical waves. The second refraction layer having a large refractive index is located in the outermost layer where the light enters. The thickness of the second refraction layer, The thickness of the first refraction layer can be made smaller than that of the first refraction layer, so that the constructive interference can be made larger, so that the reflection effect becomes larger and the light extraction efficiency can be increased.

The semiconductor reflection layer 107 may include an AlAs / AlGaAs layer. The semiconductor reflection layer 55 may be doped with a first conductive dopant, but the present invention is not limited thereto.

The composition of Al in the AlAs layer may be higher than the composition of Al in the AlGaAs layer, and the semiconductor reflection layer 115 having such a structure can effectively reflect light in a red range wavelength.

Next, a light emitting structure 110 including a first conductive type first semiconductor layer 112, an active layer 114, and a second conductive type second semiconductor layer 116 is formed on the semiconductor reflection layer 107 .

The first conductive type first semiconductor layer 112 may be formed of a compound semiconductor such as a Group III-V-V, Group-VI-VI, or the like, and may be doped with a first conductive type dopant . When the first conductive type first semiconductor layer 112 is an n-type semiconductor layer, it may include Si, Ge, Sn, Se, and Te as an n-type dopant.

The first conductive type first semiconductor layer 112 may be _{In x Al y Ga 1-xy} P (0≤x≤1, 0≤y≤1, 0≤x + y≤1) or In _x Al _y Ga _{1 -xy} N (0? x? 1, 0? y? 1, 0? x + y? 1).

The first conductive type first semiconductor layer 112 may be formed of any one or more of AlGaP, InGaP, AlInGaP, InP, GaN, InN, AlN, InGaN, AlGaN, InAlGaN, AlInN, AlGaAs, InGaAs, AlInGaAs, have.

The first conductive semiconductor layer 112 may be formed using a chemical vapor deposition (CVD) method or molecular beam epitaxy (MBE), sputtering, or vapor phase epitaxy (HVPE) It is not.

Next, the active layer 114 is formed on the first conductive type first semiconductor layer 112.

In the active layer 114, electrons injected through the first conductive type first semiconductor layer 112 and holes injected through the second conductive type second semiconductor layer 116 formed thereafter mutually meet to form an active layer (light emitting layer) It is a layer that emits light with energy determined by its inherent energy band.

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

The active layer 114 may include a well layer / barrier layer structure. For example, the active layer 114 may include one or more of a pair of GaInP / AlGaInP, GaP / AlGaP, InGaP / AlGaP, InGaN / GaN, InGaN / InGaN, GaN / AlGaN, InAlGaN / GaN, GaAs / AlGaAs, But the present invention 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.

Next, the second conductive type second semiconductor layer 116 may be formed of a semiconductor compound. 3-group-5, group-2-group-6, and the like, and the second conductivity type dopant may be doped.

For example, the second conductive type second semiconductor layer 116 may be formed of In _x Al _y Ga _1-xy P (0? _X? 1, 0? _Y? 1, 0? _X + And a semiconductor material having a composition formula of Al _y Ga _1-xy N (0? X? 1, 0? _Y? 1, 0? X + y? 1). When the second conductive type second semiconductor layer 116 is a p-type semiconductor layer, the p-type dopant may include Mg, Zn, Ca, Sr, and Ba.

The first conductive type first semiconductor layer 112 may be an n-type semiconductor layer, and the second conductive type second semiconductor layer 116 may be a p-type semiconductor layer. However, the present invention is not limited thereto. For example, in the embodiment, the first conductive type first semiconductor layer 112 may be a p-type semiconductor layer, and the second conductive type second semiconductor layer 116 may be an n-type semiconductor layer.

On the second conductive type second semiconductor layer 116, a semiconductor, for example, 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 110 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.

10, a second conductive type third semiconductor layer 123, a second conductive type fourth semiconductor layer 124, and a second conductive type semiconductor layer 124 are formed on the second conductive type second semiconductor layer 116, 5 semiconductor layer 125 may be formed.

The second conductive type third semiconductor layer 123 may include an (Al _x Ga _{1 -x} ) InP layer (0 _{? X} ? 1). The composition of Al in the second conductive type third semiconductor layer 123 may vary.

For example, the composition of Al in the second conductive type third semiconductor layer 123 may gradually increase from the active layer 114 toward the second conductive type fifth semiconductor layer 125.

The second conductive type third semiconductor layer 123 is formed between the active layer 114 and the second conductive type second semiconductor layer 122 so that the composition of Al gradually changes, (Eg) buffer layer can be formed.

In the comparative example, when the Eg buffer layer is not present, that is, when the second conductive type third semiconductor layer 123 is absent, Vf increases as the current is injected during the reliability life test.

On the other hand, in the embodiment, when the second conductive type third semiconductor layer 123 which is the Eg buffer layer exists between the active layer 114 and the second conductive type second semiconductor layer 122, the change rate of the operating voltage Vf Was kept very stable.

Next, the second conductive type fourth semiconductor layer 124 may include a p-type GaP layer of a first concentration, and the fifth semiconductor layer 125 may include a p-type GaP layer of a second concentration can do.

The doping concentration of the second conductive type element of the second conductive type fourth semiconductor layer 124 may be lower than the doping concentration of the second conductive type element of the second conductive type fifth semiconductor layer 125 .

For example, in the embodiment, the doping concentration of Mg, which is the second conductive type element of the second conductive type fourth semiconductor layer 124, is the second conductive type element of the fifth conductive type semiconductor layer 125 May be lower than the doping concentration of Mg.

For example, the second conductive type fourth semiconductor layer 124 is a GaP layer, a p-type dopant is Mg, and can be doped, the composition (concentration) is ^{1X10 16 ~ 5X10 17 (atoms /} cm -3) Lt; / RTI >

For example, the second conductive type fifth semiconductor layer 125 may be a GaP layer, may be doped with Mg as a p-type dopant, and may have a concentration of 5 × 10 ¹⁶ to 1 × ^{10 18} atoms / cm ^-3 have.

The doping concentration of the second conductive type semiconductor layer of the second conductive type fourth semiconductor layer 124 may be lower than the doping concentration of the second conductive type semiconductor layer 122 of the second conductive type semiconductor layer 122.

For example, the Mg doping concentration, which is the second conductive type element of the second conductive type fourth semiconductor layer 124, is higher than the doping concentration of Mg, which is the second conductive type element of the second conductive type second semiconductor layer 122 ≪ / RTI >

For example, the second conductive type second semiconductor layer 122 may be an AlGaInP layer, which may be doped with Mg as a p-type dopant, and may have a concentration of 5 × 10 ¹⁶ to 1 × ^{10 18} atoms / cm ^-3 have.

According to the prior art, the dopant of the second conductive type fifth semiconductor layer 125, for example, Mg is diffused into the active layer region according to the current injection during the LED lifetime test, .

In order to prevent the light flux from dropping due to the diffusion of the dopant of the second conductive type fifth semiconductor layer 125, the doping concentration of Mg, which is the second conductive type element of the fifth conductive type semiconductor layer 125 of the second conductive type, The second conductive type fourth semiconductor layer 124 is interposed between the second conductive type fifth semiconductor layer 125 and the second conductive type second semiconductor layer 122 to diffuse the dopant, By trapping Mg, the diffusion of the dopant is cut off, so that the light flux does not fall and the initial value is maintained.

In the comparative example, as shown in FIG. 3A, the light flux deviates from the predetermined tolerance range (± 10%) according to the current injection (X axis) during the LED life test. On the other hand, in the embodiment, as shown in FIG. 3B, the luminous flux was maintained without deviating from the predetermined tolerance range (± 10%) according to the current injection (X axis) during the LED life test.

The thickness of the second conductive type fourth semiconductor layer 124 may be smaller than the thickness of the second conductive type fifth semiconductor layer 125 in the embodiment. For example, the thickness of the second conductive type fourth semiconductor layer 124 may be about 1500 Å to 5000 Å, and the thickness of the second conductive type fifth semiconductor layer 125 may be about 20,000 Å to 50,000 Å .

The thickness of the second conductive type fifth semiconductor layer 125 may be greater than the thickness of the second conductive type second semiconductor layer 122 in the embodiment.

For example, the thickness of the second conductive type fifth semiconductor layer 125 may be about 10 times greater than the thickness of the second conductive type second semiconductor layer 122. This improves the reliability of the red light emitting device according to the embodiment, and the light flux can be improved.

For example, the thickness of the second conductive type fifth semiconductor layer 125 may be 8,000 to 140,000, and the thickness of the second conductive type second semiconductor layer 122 may be 2,000 to 6,000. have.

As shown in FIGS. 4 and 5, according to the embodiment, when the thickness of the second conductive type fifth semiconductor layer 125 serving as a current spreading and window in the chip is greater than the thickness of the second conductive type The operation voltage Vf and the luminous flux can be improved by 10 times or more as compared with the second semiconductor layer 122.

8, in the embodiment, the fifth semiconductor layer 125 of the second conductivity type has a structure in which a GaP layer 125a / In _x Ga _1-x P layer (0 _{? X?} 1) 125b Superlattice structure.

The second conductive type fifth semiconductor layer 125 may include a third GaP layer 125c doped with a second conductive dopant. The second conductive dopant may be a p-type conductive dopant, but is not limited thereto.

The second conductivity type fifth semiconductor layer 125 may be doped with a second conductivity type dopant and the second conductivity type dopant having a concentration lower than the first concentration may be doped in the GaP layer 125a. . The In _x Ga _1-x P layer (where 0 _{? X?} 1) 125b may not be doped with the second conductivity type dopant.

For example, the second conductivity type fifth semiconductor layer 125 has a Mg of about 10X10 ¹⁸ concentration may be doped, GaP layer (125a) has may be Mg-doped of 10X10 ¹⁷ concentration, the In _x Ga _{1 -x} P layer (where 0? x? 1) 125b may not be doped with the second conductive type dopant, but the present invention is not limited thereto.

Accordingly, the second conductive type fifth semiconductor layer 125 may have a superlattice structure of a GaP layer 125a / In _x Ga _1-x P layer (0 _{? X?} 1) 125b And the In _x Ga _1-x P layer (where 0 _{? X?} 1) 125b has a low energy level and the GaP layer 125a is an In _x Ga _1-x P layer 1) (125b).

Next, a light-transmitting electrode layer 140 may be formed on the second conductive type fifth semiconductor layer 125.

The transmissive electrode layer 140 may include an ohmic layer and may be formed by laminating a single metal, a metal alloy, or a metal oxide so as to efficiently inject holes.

For example, the light transmitting electrode layer 140 may be formed of a superior material in electrical contact with a semiconductor. For example, the light transmitting electrode layer 140 may be formed of indium tin oxide (ITO), indium zinc oxide (IZO), indium zinc oxide (IZTO), indium aluminum zinc oxide (IAZO), indium gallium zinc oxide (ZnO), indium gallium tin oxide (AZO), aluminum zinc oxide (AZO), antimony tin oxide (ATO), gallium zinc oxide (GZO), IZON nitride, AGZO Ag, Ni, Cr, Ti, Al, Rh, Pd, Ir, Ru, Mg, Zn, Pt, Ni, IrOx / Au, and Ni / IrOx / , Au, and Hf, and is not limited to such a material.

Next, as shown in FIG. 11, a second electrode 152 may be formed on the light transmitting electrode layer 140, and a first electrode 151 may be formed on the lower side of the substrate 105.

The second electrode 152 may be electrically connected to the transparent electrode layer 140. The second electrode 152 may include a contact layer (not shown), an intermediate layer (not shown), and an upper layer (not shown). The contact layer may include a material selected from the group consisting of Cr, V, W, Ti, and Zn to realize ohmic contact. The intermediate layer may be formed of a material selected from Ni, Cu, Al, and the like. The upper layer may comprise, for example, Au.

The first electrode 151 may be a conductive metal layer. For example, the first electrode 151 may be formed of a semiconductor substrate (e.g., Si, Ge, GaN, GaAs) doped with Ti, Cr, Ni, Al, Pt, Au, W, Cu, , ZnO, SiC, SiGe, and the like).

12 is a cross-sectional view of a light emitting device according to the third embodiment.

The light emitting device according to the third embodiment can employ the features of the first and second embodiments, and will be described below mainly on the main features of the third embodiment.

In the light emitting device according to the third embodiment, the second electrode layer 140 may be disposed under the light emitting structure 110.

The second electrode layer 140 may include a second ohmic layer 141, a metal reflection layer 142, a bonding layer 144, a support substrate 146, and a lower electrode 148.

The second ohmic layer 141 may partially contact the second conductive type fifth semiconductor layer 125 and the non-directional reflective layer 132 may be disposed between the second ohmic layers 141.

For example, the second ohmic layer 141 may be formed of a good material in electrical contact with the semiconductor. For example, the second ohmic layer 141 may include at least one of ITO (indium tin oxide), IZO (indium zinc oxide), IZTO (indium zinc tin oxide), IAZO (indium aluminum zinc oxide), IGZO , IGTO (indium gallium tin oxide), AZO (aluminum zinc oxide), ATO (antimony tin oxide), GZO (gallium zinc oxide), IZON (IZO Nitride), AGZO ), ZnO, IrOx, RuOx, NiO, RuOx / ITO, Ni / IrOx / Au and Ni / IrOx / Au / ITO, Ag, Ni, Cr, Ti, Al, Rh, Pd, , Pt, Au, and Hf, and is not limited to such a material.

The non-directional reflection layer 132 may include a metal-based reflection layer (not shown) and an insulating low-refractive index layer (not shown) formed on the metal-based reflection layer. The metal-based reflective layer may be Ag or Al, and the insulating low-refractive index layer may be a transparent material such as SiO ₂ , Si ₃ N ₄ , or MgO, but is not limited thereto.

The metal reflection layer 142 may be formed of a material having high electrical contact and high reflectivity. For example, the metal reflective layer 142 may be formed of a metal or an alloy including at least one of Pd, Ir, Ru, Mg, Zn, Pt, Ag, Ni, Al, Rh, Au and Hf.

The bonding layer 144 may be nickel (Ni), titanium (Ti), gold (Au), or an alloy thereof, but is not limited thereto.

The support member 70 may be formed of a material such as a carrier wafer (for example, GaN, Si, Ge, GaAs, ZnO, SiGe, SiC or the like), copper (Cu), gold (Au), copper alloy (Ni-nickel), copper-tungsten (Cu-W), and the like.

The lower electrode 148 may be formed of at least one of Ti, Cr, Ni, Al, Pt, Au, W, Cu, Mo and Cu-W.

A predetermined light extraction pattern R may be formed on the light emitting structure 110. For example, a light extraction pattern R may be formed by forming a roughness on the top surface of the first conductive type first semiconductor layer 112 by a dry or wet etching process to improve light extraction efficiency.

A pad electrode 174 may be formed on the first conductive type first semiconductor layer 112.

A branched electrode 172 is formed on the first conductive type first semiconductor layer 112 with a third ohmic layer 171 interposed therebetween and the pad electrode 174 May be formed.

   The pad electrode 174 may contact the first conductive type second semiconductor layer 112 and the branched electrode 172 at the same time and the pad electrode 174 may contact the first conductive type second semiconductor layer 112 ) Is not an ohmic contact due to short-circuit contact or the like, so that the current injection rate is low, so that the current can be diffused and the light output can be improved.

The third ohmic layer 171 may be formed of an excellent material in electrical contact with the semiconductor. For example, the third ohmic layer 171 may be formed of Ag, Ni, Cr, Ti, Al, Rh, Pd, Ir, Ru, Mg, Zn, Pt, Au, Hf, ITO, IZO indium zinc oxide, indium zinc oxide (IZTO), indium aluminum zinc oxide (IAZO), indium gallium zinc oxide (IGZO), indium gallium tin oxide (IGTO), aluminum zinc oxide (AZO), antimony tin oxide , Gallium zinc oxide (GZO), IZON nitride, IZO (Al-Ga ZnO), IGZO (In-Ga ZnO), ZnO, IrOx, RuOx, NiO, RuOx / ITO, Ni / IrOx / / IrOx / Au / ITO, and is not limited to these materials.

The pad electrode 174 and the branch electrode 172 may be formed of at least one of Ti, Cr, Ni, Al, Pt, Au, W, Cu, Mo and Cu-W.

A first passivation layer 160 may be formed on the upper surface and side surfaces of the light emitting structure 110 and a second passivation layer 162 may be formed on a side surface and a part of the upper surface of the pad electrode 174. [

The first passivation layer 160 and the second passivation layer 162 may be formed of an insulating material such as oxide or nitride. However, the present invention is not limited thereto.

A plurality of red light emitting devices according to the embodiments may be arrayed on a substrate in a package form, and a light guide plate, a prism sheet, a diffusion sheet, a fluorescent sheet, and the like may be disposed on a path of light emitted from the light emitting device package .

13 is a view for explaining a light emitting device package 200 provided with a red light emitting device according to embodiments.

The light emitting device package 200 according to the embodiment includes a package body 205, a third electrode layer 213 and a fourth electrode layer 214 provided on the package body 205, a package body 205, A red light emitting element 100 provided on the third electrode layer 213 and electrically connected to the fourth electrode layer 214 and a phosphor member (not shown) 240).

The third electrode layer 213 and the fourth electrode layer 214 are electrically isolated from each other and the third electrode layer 213 serves to supply power to the red light emitting device 100 by the wire 230 . The third electrode layer 213 and the fourth electrode layer 214 may function to increase the light efficiency by reflecting the light generated from the red light emitting device 100. In the red light emitting device 100, And may also serve to discharge generated heat to the outside.

The red light emitting device 100 may be electrically connected to the third electrode layer 213 and / or the fourth electrode layer 214 by any one of wire, flip chip, and die bonding methods.

The red light emitting device according to the embodiment can be applied to a backlight unit, a lighting unit, a display device, a pointing device, a lamp, a streetlight, a vehicle lighting device, a vehicle display device, a smart watch, but is not limited thereto.

14 is an exploded perspective view of an illumination system 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.

The light source module 2200 may include a light source unit 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 through which the plurality of light source portions 2210 and the connector 2250 are inserted.

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

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.

A first conductive type first semiconductor layer (112); An active layer 114;
A second conductive type second semiconductor layer (116); The second conductive type third semiconductor layer 123,
A second conductive type fourth semiconductor layer (124); A fifth conductive type semiconductor layer 125;

Claims (10)

A first conductive type first semiconductor layer;
An active layer on the first conductive type semiconductor layer;
A second conductive type second semiconductor layer on the active layer;
A second conductive type fourth semiconductor layer on the second conductive type second semiconductor layer; And
And a second conductive type fifth semiconductor layer on the second conductive type fourth semiconductor layer,
The doping concentration of the second conductive type element of the second conductive type fourth semiconductor layer is
And the doping concentration of the second conductive type element of the second conductive type fifth semiconductor layer is lower than the doping concentration of the second conductive type element of the second conductive type fifth semiconductor layer. The method according to claim 1,
The doping concentration of the second conductive type element of the second conductive type fourth semiconductor layer is
And the doping concentration of the second conductive type element of the second conductive type second semiconductor layer is lower than the doping concentration of the second conductive type element of the second conductive type second semiconductor layer. The method according to claim 1,
The thickness of the second conductive type fourth semiconductor layer
And the thickness of the second conductive type fifth semiconductor layer is less than the thickness of the second conductive type fifth semiconductor layer. The method according to claim 1,
The thickness of the second conductive type fifth semiconductor layer
And the thickness of the second conductive type second semiconductor layer is larger than that of the second conductive type second semiconductor layer. The method according to claim 1,
And a second conductive type third semiconductor layer between the active layer and the second conductive type fourth semiconductor layer. 6. The method of claim 5,
The second conductive type third semiconductor layer
(Al _x Ga _1-x ) InP layer (where 0 _{? X} ? 1). The method according to claim 6,
And the composition of Al in the second conductive type third semiconductor layer is changed. 8. The method of claim 7,
The composition of Al in the second conductive type third semiconductor layer is
And the active layer gradually increases in the direction of the second conductive type fifth semiconductor layer. The method according to claim 6,
The second conductive type fifth semiconductor layer
A superlattice structure of a GaP layer 125a / In _x Ga _1-x P layer (where 0 _{? X?} 1) 125b. A lighting system comprising a light emitting unit comprising a red light emitting element according to any one of claims 1 to 9.

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