KR20150065284A - Light emitting device and lighting system - Google Patents

Abstract

The present invention relates to a light emitting device, a method for manufacturing the light emitting device, a light emitting device package, and a lighting system. According to an embodiment, the light emitting device comprises: a first conductivity semiconductor layer; a In_xAl_yGa_(1-x-y)N/GaN layer (0<x<1, 0<y<1) (17) on the first conductivity semiconductor layer (11); an active layer (12) on the In_xAl_yGa_(1-x-y)N/GaN layer; and a second conductivity semiconductor layer (13) on the active layer (12), wherein the active layer (12) may include a In_pGa_(1-p)N well layer (0<p<1) (12a) and a GaN barrier layer (12b).

Description

[0001] LIGHT EMITTING DEVICE AND LIGHTING SYSTEM [0002]

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

Light Emitting Device is a pn junction diode whose electrical energy is converted into light energy. It can be produced from compound semiconductor such as group III and group V on the periodic table and by controlling the composition ratio of compound semiconductor, It is possible.

When a forward voltage is applied to the light emitting device, electrons in the n-layer and holes in the p-layer are coupled to emit energy corresponding to the band gap energy of the conduction band and the valance band. Is mainly emitted in the form of heat or light, and when emitted in the form of light, becomes a light emitting element.

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

The epitaxial layer of a general InGaN / GaN structure of a conventional light emitting device has a lattice mismatch at the interface between two thin films due to the lattice constant difference between InGaN and GaN, Polarization occurs, and a piezoelectric field occurs across the epi structure.

The application of a high current to the epitaxial structure in the presence of such a piezo field seriously bands the band gap, resulting in a low potential barrier at the interface between the two films, (Carrier Confinement) function is deteriorated and the electron overflow phenomenon is promoted, so that the number of non-radiative carriers increases, and the luminous efficiency sharply drops.

Also, if the current density is gradually increased in the epitaxial structure in the state where the electron overflow exists, the band gap is bent, thereby gradually increasing the electron overflow phenomenon even with the InGaN well including the same In content .

The overflow of electrons generated in the well having the low potential barrier layer can reduce the number of light (Photon, hv) generated by the MQW in a large number.

Embodiments provide a light emitting device, a method of manufacturing a light emitting device, a light emitting device package, and an illumination system capable of increasing an optical efficiency by preventing an electron overflow phenomenon in an epitaxial structure.

The light emitting device according to the embodiment includes a first conductive semiconductor layer 11; An In _x Al _y Ga _{1 -x- y} N / GaN layer (0 <x <1, 0 <y <1) (17) is formed on the first conductive semiconductor layer 11; An active layer 12 on the In _x Al _y Ga _{1 -x- y} N / GaN layer 17; And a second conductivity type semiconductor layer 13 on the active layer 12. The active layer 12 includes an In _p Ga _{1 - p} N well layer (where 0 <p <1) 12a and a GaN And a barrier layer 12b.

The relationship between the composition x of In in the In _x Al _y Ga _{1 -x- y} N / GaN layer 17 and the composition p of In in the well layer 12a is 0.75? X / p? .

The composition range (y) of Al in the In _x Al _y Ga _{1 -x- y} N / GaN layer (where 0 <x <1, 0 <y <1) (17) may be 0 <y ≦ 0.02 .

In addition, the illumination device according to the embodiment may include a light emitting module including the light emitting device.

According to the light emitting device, the method of manufacturing the light emitting device, the light emitting device package, and the illumination system according to the embodiments, it is possible to prevent the electron overflow phenomenon in the epitaxial structure, thereby increasing the light efficiency.

1 is a cross-sectional view of a light emitting device according to an embodiment.
2 is an energy bandgap diagram of a light emitting device according to an embodiment.
3 is a first exemplary internal quantum efficiency example of a light emitting device according to an embodiment.
4 is a second exemplary internal quantum efficiency of a light emitting device according to an embodiment.
5 is a third exemplary internal quantum efficiency of a light emitting device according to an embodiment.
6 to 8 are cross-sectional views illustrating a method of manufacturing a light emitting device according to an embodiment.
9 is a cross-sectional view of a light emitting device according to another embodiment.
10 is a cross-sectional view of a light emitting device package according to an embodiment.
11 is a diagram of a lighting device according to an embodiment.

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

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

(Example)

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

The light emitting device 100 according to the embodiment includes a first conductivity type semiconductor layer 11 and an In _x Al _y Ga _{1 -x- y} N / GaN layer on the first conductivity type semiconductor layer 11, 1), 0 <x <1, 0 <y <1) 17, an active layer 12 on the In _x Al _y Ga _{1 -xy} N / GaN layer 17, -Type semiconductor layer (13).

2 is an energy bandgap diagram of the light emitting device according to the embodiment.

In the embodiment, the In _x Al _y Ga _{1 -x- y} N / GaN layer 17 may include a superlattice structure of In _x Al _y Ga _{1 -x- y} N (17a) / GaN (17b) It is not limited.

In an embodiment, the active layer 12 is In _p Ga _{1 - p} N well layer (where, 0 <p <1) ( 12a) and may include a GaN barrier layer (12b), the In _x Al _y Ga _{1 -x- y The} relationship between the composition (x) of In in the N / GaN layer 17 and the composition (p) of In in the well layer 12a may be in the range of 0.75? x / p? 1.0.

 3 is a first exemplary view of the internal quantum efficiency of the light emitting device according to the embodiment and the internal quantum efficiency Ref of the comparative example.

In FIG. 3, the In _x Al _y Ga _{1 -x- y} N / GaN layer 17 of the embodiment is an example of In _{0 .13} Al _{0 .02} Ga _{0 .85} N / GaN, But is not limited thereto.

In general, Piezoelectric Fields in the entire Epi Structure are characterized by high current driving which seriously bends the bandgap and deepens the electron overflow phenomenon. The number of photons (hv) generated in the active layer can be reduced.

In the embodiment, an In _x Al _y Ga _{1 -x- y} N / GaN layer 17 may be disposed under the active layer 12 for implementing a PFRS (Piezoelectric Field Reduction Structure) to improve the piezoelectric field phenomenon.

In order to realize PFRS (Piezoelectric Field Reduction Structure) in the embodiment, the role of the super lattice structure of In _x Al _y Ga _{1 -x- y} N / GaN layer 17 disposed under the active layer 12 is important.

The electrons injected into the active layer can enhance the carrier confinement function according to the In / Al composition in the In _x Al _y Ga _{1 -x- y} N / GaN structure, Transfer Function can be enhanced to increase the number of Photon (hv) excited to increase Emission Intensity and IQE (Internal Quantum Efficiency) on the Wave / Energy Separation.

For example, according to the embodiment, Bandgap energy is formed by constituting about 13% of In and about 2% of Al in the In _x Al _y Ga _{1 -x- y} N / GaN layer 17 On the other hand, a potential barrier occurs at the interface between two thin films due to the band gap energy difference between InAlGaN and GaN in an actual epitaxial layer, and a piezoelectric field existing across the n / p- ) Is reduced and the carrier confinement of the injected electrons is improved so as to increase the probability of existence of carriers in a specific well and to promote radiative recombination to improve the luminous efficiency .

4 is a second exemplary internal quantum efficiency example of the light emitting device according to the embodiment, and is an Al level optimization experiment result in the comparative example (Ref), the first embodiment (E1), and the second embodiment (E2) .

The composition range (y) of Al in the In _x Al _y Ga _{1 -x- y} N / GaN layer (where 0 <x <1, 0 <y <1) (17) satisfies 0 <y≤0.02 Lt; / RTI &gt;

In order to improve the electron overflow phenomenon and the non-radiative recombination, the embodiment has a low concentration Al composition of 2% or less so as to reduce the InAlGaN / GaN polarity The In _x Al _y Ga _{1 -x- y} N / GaN layer 17 is designed to relax the band bending phenomenon at high current driving and to improve the carrier confinement function of the injected electron Carrier Confinement Function).

5 is a third exemplary internal quantum efficiency example of the light emitting device according to the embodiment, and is an In level optimization experiment result in the comparative example (Ref), the first embodiment (E1), and the third embodiment (E3) .

In the embodiment, the relationship between the composition (x) of In in the In _x Al _y Ga _{1 -x- y} N / GaN layer 17 and the composition (p) of In in the well layer 12a is 0.75 x / p &Lt; / RTI &gt;

For example, the composition range (x) of In in the In _x Al _y Ga _{1 -x- y} N / GaN layer (where 0 <x <1, 0 <y < 0.13.

In the embodiment, the In concentration is designed to be higher than the In concentration of the conventional strain relaxation layer so that the InAlGaN / GaN polarity is reduced and the difference in lattice constant between the InAlGaN / GaN layer and the active layer is reduced. The band bending phenomenon can be mitigated and the carrier transfer function can be increased.

In an embodiment, the In _x Al _y Ga _{1 -x- y} N / GaN layer 17 may be an un-doped layer.

Alternatively, the In _x Al _y Ga _{1 -x- y} N / GaN layer 17 may be a layer doped with a first conductivity type and may have physical properties different from those of the active layer have.

According to the light emitting device, the method of manufacturing the light emitting device, the light emitting device package, and the illumination system according to the embodiments, it is possible to prevent the electron overflow phenomenon in the epitaxial structure, thereby increasing the light efficiency.

Hereinafter, a method of manufacturing a light emitting device according to an embodiment will be described with reference to FIGS.

The first conductivity type semiconductor layer 11, the active layer 12, and the second conductivity type semiconductor layer 13 can be formed on the substrate 5 as shown in FIG. 6 . The first conductive semiconductor layer 11, the active layer 12, and the second conductive semiconductor layer 13 may be defined as a light emitting structure 10.

The substrate 5 may be formed of at least one of, for example, a sapphire substrate (Al ₂ O ₃ ), SiC, GaAs, GaN, ZnO, Si, GaP, InP and Ge. A buffer layer 14 may be further formed between the first conductive semiconductor layer 11 and the substrate 5.

For example, the first conductivity type semiconductor layer 11 is formed of an n-type semiconductor layer doped with an n-type dopant as a first conductivity type dopant, and the second conductivity type semiconductor layer 13 is formed of an n- Type semiconductor layer to which a p-type dopant is added. The first conductivity type semiconductor layer 11 may be formed of a p-type semiconductor layer, and the second conductivity type semiconductor layer 13 may be formed of an n-type semiconductor layer.

The first conductive semiconductor layer 11 may include, for example, an n-type semiconductor layer. The first conductive semiconductor layer 11 is a semiconductor material having a composition formula of In _x Al _y Ga _{1 -x- y} N (0? X? 1, 0? _Y? 1, 0? _X + . The first conductivity type semiconductor layer 11 may be selected from InAlGaN, GaN, AlGaN, AlInN, InGaN, AlN, InN and the like, and an n-type dopant such as Si, Ge, Sn, .

The active layer 12 is formed in such a manner that electrons (or holes) injected through the first conductive type semiconductor layer 11 and holes (or electrons) injected through the second conductive type semiconductor layer 13 meet with each other, And is a layer that emits light due to a band gap difference of an energy band according to a material of the active layer 12. [

The second conductive semiconductor layer 13 may be formed of, for example, a p-type semiconductor layer. The second conductivity type semiconductor layer 13 is a semiconductor material having a composition formula of In _x Al _y Ga _{1 -x- y} N (0? X? 1, 0? _Y? 1, 0? _X + . The second conductivity type semiconductor layer 13 may be selected from among InAlGaN, GaN, AlGaN, InGaN, AlInN, AlN and InN. The p-type dopant such as Mg, Zn, Ca, .

Meanwhile, the first conductive semiconductor layer 11 may include a p-type semiconductor layer and the second conductive semiconductor layer 13 may include an n-type semiconductor layer. In addition, a semiconductor layer including an n-type or p-type semiconductor layer may be further formed on the second conductive type semiconductor layer 13. Thus, the light emitting structure 10 may include np, pn, npn, Or a structure thereof. The doping concentration of impurities in the first conductivity type semiconductor layer 11 and the second conductivity type semiconductor layer 13 may be uniform or non-uniform. That is, the structure of the light emitting structure 10 may be variously formed, but the present invention is not limited thereto.

Also, a first conductive InGaN / GaN superlattice structure or an InGaN / InGaN superlattice structure may be formed between the first conductive semiconductor layer 11 and the active layer 12. In addition, a second conductive type AlGaN layer may be formed between the second conductive type semiconductor layer 13 and the active layer 12.

2 illustrates a light emitting device according to an embodiment of the present invention with reference to a bandgap diagram of a light emitting device according to an embodiment.

2 is an energy bandgap diagram of the light emitting device according to the embodiment.

In the embodiment, the In _x Al _y Ga _{1 -x- y} N / GaN layer 17 may include a superlattice structure, but is not limited thereto.

In an embodiment, the active layer 12 is In _p Ga _{1 - p} N well layer (where, 0 <p <1) ( 12a) and may include a GaN barrier layer (12b), the In _x Al _y Ga _{1 -x- y The} relationship between the composition (x) of In in the N / GaN layer 17 and the composition (p) of In in the well layer 12a may be in the range of 0.75? x / p? 1.0.

In the embodiment, the In _x Al _y Ga _{1 -xy} N / GaN layer 17 may be disposed under the active layer 12 to improve the piezoelectric field effect.

According to the embodiment, when band gap energy is formed by constituting about 13% of In and about 2% of Al in the In _x Al _y Ga _{1 -x- y} N / GaN layer 17, The difference in the band gap energy between InAlGaN and GaN causes a potential barrier at the interface between two thin films, which reduces the field of the piezoelectric field, restrains the carrier of the injected electrons, increases the probability of carrier presence in a specific well, The efficiency can be improved.

Next, as shown in FIG. 7, the light emitting structure 10 may be etched to expose a portion of the first conductivity type semiconductor layer 11. At this time, the etching may be performed by wet etching or dry etching.

A channel layer 30, an ohmic contact pattern 15, and a reflective layer 17 may be formed on the light emitting structure 10.

For example, the channel layer 30 is Si0 _2, Si _x O _y, Si ₃ N _4, Si _x N _y, SiO _x N _y, Al ₂ O _3, at least one from the group consisting of TiO _2, AlN, etc. May be selected and formed.

The ohmic contact pattern 15 may be disposed between the reflective layer 17 and the second conductive semiconductor layer 13. The ohmic contact pattern 15 may be disposed in contact with the second conductive semiconductor layer 13.

The ohmic contact pattern 15 may be formed in ohmic contact with the light emitting structure 10. The reflective layer 17 may be electrically connected to the second conductive semiconductor layer 13. The ohmic contact pattern 15 may include a region in ohmic contact with the light emitting structure 10.

The ohmic contact pattern 15 may be formed of, for example, a transparent conductive oxide film. The ohmic contact pattern 15 may be formed of a metal such as ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide), AZO (Aluminum Zinc Oxide), AGZO (Aluminum Gallium Zinc Oxide), IZTO (Indium Zinc Tin Oxide) IZO (IZO Nitride), ZnO, IrOx, RuOx, NiO, Pt (indium gallium zinc oxide), IGTO (indium gallium tin oxide), ATO , Ag, and Ti.

The reflective layer 17 may be formed of a material having a high reflectivity. For example, the reflective layer 17 may be formed of a metal or an alloy including at least one of Ag, Ni, Al, Rh, Pd, Ir, Ru, Mg, Zn, Pt, Cu, Au and Hf. The reflective layer 17 may be formed of a metal or an alloy of ITO (Indium-Tin-Oxide), IZO (Indium-Zinc-Oxide), IZTO (Indium-Zinc-Tin-Oxide), IAZO (Indium- A transparent conductive material such as indium-gallium-oxide (IGZO), indium-gallium-zinc-oxide (IGTO), aluminum-zinc oxide And may be formed in multiple layers. For example, in an embodiment, the reflective layer 17 may include at least one of Ag, Al, Ag-Pd-Cu alloy, or Ag-Cu alloy.

For example, the reflective layer 17 may include an Ag layer and an Ni layer alternately or may include a Ni / Ag / Ni layer, a Ti layer, and a Pt layer. The ohmic contact pattern 15 may be formed under the reflective layer 17 and at least a part of the ohmic contact pattern 15 may be in ohmic contact with the light emitting structure 10 through the reflective layer 17.

A metal layer 50, a bonding layer 60, a supporting member 70, and a temporary substrate 90 may be formed on the reflective layer 17.

The metal layer 50 may include at least one of Au, Cu, Ni, Ti, Ti, W, Cr, W, Pt, V, Fe and Mo. The metal layer 50 may function as a diffusion barrier layer.

According to the embodiment, the first electrode layer electrically connected to the second conductivity type semiconductor layer 13 may include at least one of a reflective layer, an ohmic contact layer, and a metal layer. According to the embodiment, the first electrode layer may include a reflective layer, an ohmic contact layer, and a metal layer, and may include one layer or two layers.

The metal layer 50 may prevent a material contained in the bonding layer 60 from diffusing toward the reflective layer 17 in the process of providing the bonding layer 60. The second metal layer 50 may prevent a material such as tin contained in the bonding layer 60 from affecting the reflective layer 17.

The bonding layer 60 may include at least one of Ti, Au, Sn, Ni, Cr, Ga, In, Bi, Cu, Ag, Nb, Pd, . The support member 70 supports the light emitting structure 10 according to the embodiment and can perform a heat dissipation function. The bonding layer 60 may be implemented as a seed layer.

The supporting member 70 may be a semiconductor substrate (for example, Si, Ge, GaN, GaAs, or the like) into which Ti, Cr, Ni, Al, Pt, Au, W, Cu, Mo, Cu- ZnO, SiC, SiGe, and the like). Further, the support member 70 may be formed of an insulating material.

The temporary substrate 90 may be formed on the support member 70. The temporary substrate 90 may be formed of at least one of a metal material, a semiconductor material, and an insulating material.

Next, as shown in FIG. 8, the substrate 5 is removed from the light emitting structure 10. As one example, the substrate 5 may be removed by a laser lift off (LLO) process. The laser lift-off process (LLO) is a process of irradiating a laser to the lower surface of the substrate 5 to peel the substrate 5 and the light emitting structure 10 from each other.

Then, an isolation etching process, a pad electrode 81 forming process, a scribing process, a reflective portion forming process, and a temporary substrate removing process may be performed. Such a process is one example, and the process sequence can be variously modified as needed.

According to the embodiment, isolation etching is performed to etch the side surface of the light emitting structure 10, and a part of the channel layer 30 can be exposed. The isolation etching can be performed by, for example, dry etching such as ICP (Inductively Coupled Plasma), but is not limited thereto.

Roughness (not shown) may be formed on the upper surface of the light emitting structure 10. A light extracting pattern may be provided on the upper surface of the light emitting structure 10. An irregular pattern may be provided on the upper surface of the light emitting structure 10. The light extracting pattern provided in the light emitting structure 10 may be formed by a PEC (Photo Electro Chemical) etching process as an example. Accordingly, according to the embodiment, the effect of extracting external light can be increased.

Next, a pad electrode 81 may be formed on the light emitting structure 10.

The pad electrode 81 may be electrically connected to the first conductive type semiconductor layer 11. A portion of the pad electrode 81 may be in contact with the first conductive semiconductor layer 11. According to the embodiment, power can be applied to the light emitting structure 10 through the pad electrode 81 and the first electrode layer 87.

The pad electrode 81 may be formed of an ohmic layer, an intermediate layer, and an upper layer. The ohmic 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 pad electrode 81 may include at least one of Cr, V, W, Ti, Zn, Ni, Cu, Al and Au.

Then, the scribing process is performed to expose the side surfaces of the channel layer 30 and the support member 70. The reflective portion 40 may be formed on the side surface of the channel layer 30 and the side surface of the supporting member 70. [ After that, the temporary substrate 90 is removed, so that individual light emitting devices can be formed.

According to the embodiment, the reflective portion 40 may be disposed on the channel layer 30. The reflector 40 may be disposed in contact with the channel layer 30. The reflective portion 40 may be disposed on a side surface of the support member 70. The reflective portion 40 may be disposed in contact with the side surface of the support member 70. According to the embodiment, the reflective portion 40 may be disposed such that a first region disposed on the channel layer 30 and a second region disposed on the side surface of the support member 70 are connected to each other.

The reflective portion 40 may be disposed on a side surface of the metal layer 50. The reflective portion 40 may be disposed in contact with a side surface of the metal layer 50. The reflective portion 40 may be disposed on a side surface of the bonding layer 60. The reflective portion 40 may be disposed in contact with the side surface of the bonding layer 60. The reflective portion 40 may be spaced apart from the light emitting structure 10. The reflective portion 40 may be disposed to be electrically insulated from the light emitting structure 10.

The reflective portion 40 may be formed of a material having a high reflectivity. For example, the reflective portion 40 may include at least one of Ag, Al, and Pt. The reflective portion 40 may be formed to a thickness of 50 nanometers to 5000 nanometers, for example.

The reflective portion 40 is formed such that light emitted from the light emitting structure 10 is incident on the channel layer 30, the metal layer 50, the bonding layer 60, and the support member 70, . That is, the reflection part 40 reflects light incident from the outside, so that light is absorbed and lost in the channel layer 30, the metal layer 50, the bonding layer 60, and the support member 70 .

As the reflector 40 is disposed, any one of the side surface of the channel layer 30, the side surface of the metal layer 50, the side surface of the bonding layer 60, and the side surface of the support member 70 may have roughness The side surfaces of the light emitting device according to the embodiment can be all implemented smoothly. That is, since the surface of the reflective portion 40 may be smoothly formed, the side surface of the channel layer 30, the side surface of the metal layer 50, the side surface of the bonding layer 60 in the scribing process, Even when a roughness or a burr is formed on any one of the side surfaces of the light emitting device 70, the side surfaces of the light emitting device according to the embodiment can be smoothly realized.

9 is a sectional view of a light emitting device 102 according to another embodiment.

Other embodiments may adopt the technical features of the above embodiment.

The light emitting device 102 according to another embodiment is an example of a horizontal light emitting device and includes a substrate 5, a first conductive semiconductor layer 11 on the substrate 5, An active layer 12 may be formed on the semiconductor layer 11 and a second conductivity type semiconductor layer 13 may be formed on the active layer 12. [

The first electrode layer 87 may be disposed on the second conductivity type semiconductor layer 13 and the first electrode layer 87 may be transparent And may include an ohmic layer.

The first pad electrode 81 and the second pad electrode 82 may be disposed on the exposed first conductivity type semiconductor layer 11 with the second electrode layer 87 and the buffer layer 14 may be disposed on the substrate 5, Lt; / RTI &gt;

10 is a view illustrating a light emitting device package to which the light emitting device according to the embodiment is applied.

10, a light emitting device package according to an embodiment includes a body 120, a first lead electrode 131 and a second lead electrode 132 disposed on the body 120, And a molding member 140 surrounding the light emitting device 100. The first and second lead electrodes 131 and 132 are electrically connected to the first and second lead electrodes 131 and 132, .

The body 120 may be formed of a silicon material, a synthetic resin material, or a metal material, and the inclined surface may be formed around the light emitting device 100.

The first lead electrode 131 and the second lead electrode 132 are electrically separated from each other to provide power to the light emitting device 100. The first lead electrode 131 and the second lead electrode 132 may increase the light efficiency by reflecting the light generated from the light emitting device 100 and the heat generated from the light emitting device 100 To the outside.

The light emitting device 100 may be disposed on the body 120 or may be disposed on the first lead electrode 131 or the second lead electrode 132.

The light emitting device 100 may be electrically connected to the first lead electrode 131 and the second lead electrode 132 by a wire, flip chip or die bonding method.

The molding member 140 may surround the light emitting device 100 to protect the light emitting device 100. In addition, the molding member 140 may include a phosphor to change the wavelength of light emitted from the light emitting device 100.

A plurality of light emitting devices or light emitting device packages according to the embodiments may be arrayed on a substrate, and a lens, a light guide plate, a prism sheet, a diffusion sheet, etc., which are optical members, may be disposed on the light path of the light emitting device package. Such a light emitting device package, a substrate, and an optical member can function as a light unit. The light unit may be implemented as a top view or a side view type and may be provided in a display device such as a portable terminal and a notebook computer, or may be variously applied to a lighting device and a pointing device. Still another embodiment may be embodied as a lighting device including the light emitting device or the light emitting device package described in the above embodiments. For example, the lighting device may include a lamp, a streetlight, an electric signboard, and a headlight.

11 is an exploded perspective view of a lighting apparatus according to an embodiment.

11, the lighting apparatus according to the embodiment includes 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 package according to an embodiment.

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

The inner surface of the cover 2100 may be coated with a milky white paint. Milky white paints may contain a diffusing agent to diffuse light. The surface roughness of the inner surface of the cover 2100 may be larger than the surface roughness of the outer surface of the cover 2100. This is for sufficiently diffusing and diffusing the light from the light source module 2200 and emitting it to the outside.

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

The light source module 2200 may be disposed on one side of the heat discharging body 2400. Accordingly, heat from the light source module 2200 is conducted to the heat discharger 2400. The light source module 2200 may include a light 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 guide groove 2310 corresponds to the substrate of the light source unit 2210 and the connector 2250.

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

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

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

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

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

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

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

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.

The first conductivity type semiconductor layer 11, the active layer 12, the second conductivity type semiconductor layer 13,
In _x Al _y Ga _{1 -x- y} N / GaN layer 17, In _p Ga _{1 - p} N well layer 12a, GaN barrier layer 12b,

Claims (13)

A first conductive semiconductor layer;
An In _x Al _y Ga _{1 -x- y} N / GaN layer (0 <x <1, 0 <y <1) on the first conductive semiconductor layer;
An active layer on the In _x Al _y Ga _{1 -x- y} N / GaN layer; And
And a second conductive semiconductor layer on the active layer,
Wherein the active layer comprises an In _p Ga _{1 - p} N well layer (where 0 <p <1) and a GaN barrier layer,
(X) of In in the In _x Al _y Ga _{1 -x- y} N / GaN layer and the composition (p) of In in the well layer is in the range of 0.75? X / p? 1.0. The method according to claim 1,
In the In _x Al _y Ga _{1 -x- y} N / GaN layer (where 0 <x <1, 0 <y <1)
The composition range (y) of Al is 0 &lt; y? 0.02. The method according to claim 1,
In the In _x Al _y Ga _{1 -x- y} N / GaN layer (where 0 <x <1, 0 <y <1)
The composition range (x) of In is 0 &lt; x &lt; = 0.13. The method according to claim 1,
The In _x Al _y Ga _{1 -x- y} N / GaN layer has a
The light-emitting element is an un-doped layer. The method according to claim 1,
The In _x Al _y Ga _{1 -x- y} N / GaN layer has a
Wherein the light emitting layer is a layer doped with the first conductivity type. The method according to claim 1,
The In _x Al _y Ga _{1 -x- y} N / GaN layer has a
A light emitting device comprising a superlattice structure. A first conductive semiconductor layer;
An In _x Al _y Ga _{1 -x- y} N / GaN layer (0 <x <1, 0 <y <1) on the first conductive semiconductor layer;
An active layer on the In _x Al _y Ga _{1 -x- y} N / GaN layer; And
And a second conductive semiconductor layer on the active layer,
Wherein the active layer comprises an In _p Ga _{1 - p} N well layer (where 0 <p <1) and a GaN barrier layer,
The composition range (y) of Al in the In _x Al _y Ga _{1 -x- y} N / GaN layer (where 0 <x <1, 0 <y <1) satisfies 0 <y? 8. The method of claim 7,
In the In _x Al _y Ga _{1 -x- y} N / GaN layer (where 0 <x <1, 0 <y <1)
The composition range (x) of In is 0 &lt; x &lt; = 0.13. 9. The method of claim 8,
(X) of In in the In _x Al _y Ga _{1 -x- y} N / GaN layer and the composition (p) of In in the well layer is in the range of 0.75? X / p? 1.0. 8. The method of claim 7,
The In _x Al _y Ga _{1 -x- y} N / GaN layer has a
The light-emitting element is an un-doped layer. 8. The method of claim 7,
The In _x Al _y Ga _{1 -x- y} N / GaN layer has a
Wherein the light emitting layer is a layer doped with the first conductivity type. 8. The method of claim 7,
The In _x Al _y Ga _{1 -x- y} N / GaN layer has a
A light emitting device comprising a superlattice structure. A lighting device comprising a light emitting module comprising the light emitting element according to any one of claims 1 to 12.

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