KR20150142229A - Light emitting device, and lighting system - Google Patents

Abstract

An embodiment relates to a light emitting device, a method of manufacturing a light emitting device, a light emitting device package and a lighting system. A light emitting device according to an embodiment may include a first conductivity type semiconductor layer; a first nitride active layer arranged on the upper side of the conductivity type semiconductor layer; a second nitride active layer arranged under the first conductivity type semiconductor layer; a second conductivity type semiconductor layer arranged on the second nitride active layer; a first electrode which is electrically connected to the first conductivity type semiconductor layer; and a second electrode which is electrically connected to the second conductivity type semiconductor layer.

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.

A light emitting device can be produced by combining p-n junction diodes having the characteristic that electric energy is converted into light energy by elements of Group III and Group V on the periodic table. LEDs can be implemented in various colors by controlling the composition ratio of compound semiconductors.

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

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 light emitting device can be classified into a lateral type and a vertical type depending on the position of the electrode.

The conventional light emitting device has a multiple quantum well structure in which an active layer is periodically repeatedly stacked with InGaN / GaN quantum wells and quantum wells. Since InGaN and GaN have different lattice constants, stress is generated by lattice mismatching Therefore, an electric field is generated inside.

As a result, the injected electrons can not effectively participate in the emission of light in the active layer due to the influence of the electric field, and leak into the hole injection layer through the active layer. This current leakage phenomenon becomes more serious as the injection current increases.

 Therefore, there is a problem of lowering the luminous efficiency due to leakage of electrons in a high-output device operating at a high current. Such a problem causes a serious problem of efficiency deterioration particularly in a long wavelength light emitting layer having a large In composition of the InGaN quantum well.

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 providing high efficiency even under a high injection current.

The light emitting device according to the embodiment includes a first conductive semiconductor layer 112; A first nitride active layer 111 disposed on the first conductive semiconductor layer 112; A second nitride active layer 114 disposed under the first conductive semiconductor layer 112; A second conductive semiconductor layer 116 disposed under the second nitride active layer 114; a first electrode 140 electrically connected to the first conductive semiconductor layer 112; And a second electrode 130 that is electrically connected to the second conductive semiconductor layer 116.

An illumination system according to an embodiment may include a light emitting module having the light emitting element.

Embodiments provide a light emitting device capable of providing a high efficiency even under a high injection current by exciting a green light source of a second light emitting layer by providing a first light emitting layer having no decrease in light emitting quantum efficiency according to an increase in injection current, Device package and illumination system.

1 is a sectional view of a light emitting device according to a first embodiment;
2 and 3 are partial enlarged views of a light emitting device according to the first embodiment.
4 is a diagram illustrating an example of the internal quantum efficiency of the light emitting device according to the embodiment and the related art.
5 is a sectional view of a light emitting device according to a second embodiment;
6 is a cross-sectional view of a light emitting device according to a third embodiment;
7 to 13 are cross-sectional views illustrating a method of manufacturing a light emitting device according to an embodiment.
14 is a sectional view of a light emitting device package according to an embodiment.
15 is a perspective view of a lighting apparatus according to an embodiment.

In the description of the embodiments, each layer (film), region, pattern or structure is referred to as being "on" or "under" the substrate, each layer (film) 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.

(Example)

FIG. 1 is a cross-sectional view of a light emitting device 100 according to a first embodiment, and FIGS. 2A and 2B are enlarged views of an A portion and a B portion of a light emitting device according to the first embodiment.

The light emitting device 100 according to the embodiment includes a first conductive semiconductor layer 112, a first nitride active layer 111 disposed on the first conductive semiconductor layer 112, A second conductive semiconductor layer 116 disposed under the second nitride active layer 114 and a second conductive semiconductor layer 116 disposed under the second conductive semiconductor layer 112. The second conductive semiconductor layer 112 is disposed under the second conductive semiconductor layer 112, A first electrode 140 electrically connected to the second conductive semiconductor layer 116 and a second electrode 130 electrically connected to the second conductive semiconductor layer 116.

The first electrode 140 may be in contact with the first conductive semiconductor layer 112 through the second conductive semiconductor layer 116.

The exemplary embodiment of the present invention includes an ohmic layer 122 and a reflective layer 124 disposed below the second conductive semiconductor layer 116. The first electrode 140 may be formed on the second conductive semiconductor layer 116, And a first penetrating electrode 142a and a lower electrode 144 passing through the ohmic layer 122 and the reflective layer 124. [

The embodiment may include a first insulating layer 152 surrounding the first penetrating electrode 142a.

The first conductive semiconductor layer 112 may be an n-GaN-based nitride semiconductor thin film as an electron injecting layer, but the present invention is not limited thereto.

The second conductive semiconductor layer 116 may be a p-GaN-based nitride semiconductor thin film as a hole injection layer, but the present invention is not limited thereto.

In an embodiment, the second nitride active layer 114 may emit ultraviolet light.

For example, as shown in FIG. 2A, the second nitride active layer 114 may include a second quantum wall 114B and a second quantum well 114W. For example, the second nitride active layer 114 may be a multi-quantum well structure nitride semiconductor thin film layer based on an InGaN quantum well and an AlGaN quantum well as a light emitting layer capable of emitting near UV at about 380 to 420 nm, It is not.

Next, the first active layer 111 may be excited by ultraviolet rays emitted from the second active layer 114 to emit visible light.

For example, as shown in FIG. 2B, the first active layer 111 may include a first quantum wall 111B and a first quantum well 111W.

For example, the first nitride active layer 111 may be a light emitting layer capable of emitting green light of about 500 to 540 nm, and may be a multiple quantum well structure nitride semiconductor thin film layer formed on the basis of an InGaN quantum well and a GaN quantum wall. But is not limited thereto.

The second electrode 130 is a p-metal electrode. The second electrode 130 is disposed on the reflective layer 130 and electrically separated from the first electrode 140.

The first electrode 140 may be an n-metal electrode that penetrates the second conductive semiconductor layer 116 and the second nitride active layer 114 to etch the first conductive semiconductor layer 112, After the hole is formed, a first insulating layer 152 is provided on the side surface of the hole, and a metal is provided in the hole to make an n-Ohmic contact with the first conductive type semiconductor layer 112 in which the metal is exposed by etching Or < / RTI >

5 is a sectional view of the light emitting device 102 according to the second embodiment.

A plurality of through electrodes may be formed in the first electrode 140. For example, the first electrode 140 may include a first penetrating electrode 142a and a second penetrating electrode, and may be separated from the reflective layer 124 by a second insulating layer 154 And the n-metal electrodes filling the individual holes can be formed to be connected to each other by the lower electrode 154.

The material of the insulating layer may include, but is not limited to, silicon oxide or silicon nitride.

In the light emitting device according to the embodiment, electrons are injected from the first conductivity type semiconductor layer 112 which is an electron injection layer, holes are injected from the second conductivity type semiconductor layer 116 which is a hole injection layer, And emits ultraviolet light from the second quantum well 114W of the second quantum well 114. [

The emitted light has an energy magnitude quantitatively determined by the second quantum well 114W, a wavelength range of about 380 to 420 nm, and the wavelength can be controlled by controlling the indium composition and the well thickness have. The smaller the In composition in the second quantum well 114W, the shorter wavelength light is emitted.

The emitted ultraviolet rays are transmitted through the first conductivity type semiconductor layer 112 to excite the first quantum well 111W in the first nitride active layer 111 to emit visible light. For example, light emitted from the first quantum well 111W may be green light, blue light, or the like, but is not limited thereto. The In composition of the first quantum well 111W may be greater than the indium composition of the second quantum well 114W.

Hereinafter, the operation principle and effects of the light emitting device according to the embodiment will be described in more detail with reference to FIGS. 1 and 4. FIG.

FIG. 4 shows the internal light emitting quantum efficiency E according to the injection current of the light emitting device according to the embodiment. For example, the second nitride active layer 114 may be an example of ultraviolet light emission of about 405 nm, but the present invention is not limited thereto.

Conventionally, a nitride semiconductor light emitting device, particularly a light emitting device emitting green light, comprises an InGaN quantum well containing indium in an amount of about 20 to 30% of In and a multiple quantum well structure light emitting layer composed of GaN quantum wall. This luminescent layer generates a large stress due to a large lattice mismatch between InGaN and GaN, thereby forming an internal stress field. As a result, electrons injected when the injection current is increased are leaked from the light emitting layer to the hole injection layer by an internal stress field, (See R in Fig. 4).

Such a phenomenon of lowering the luminous efficiency is improved as the lattice mismatch stress becomes smaller as the indium composition in the light emitting layer becomes smaller. Therefore, in the case of an ultraviolet nitride semiconductor light emitting device having a small amount of indium with an indium composition of about 1 to 5% in quantum wells like the second quantum well 114W in the second nitride active layer 114 of the embodiment, The stress due to lattice mismatch is small. Therefore, the decrease in the luminous efficiency due to the injection current is very small (see E in Fig. 4).

According to the embodiment, in order to solve the problems of the conventional green nitride semiconductor light emitting device, the second nitride active layer 114, which is an ultraviolet light emitting layer, is provided and a first nitride active layer 111, which is a green light emitting layer, do. The second nitride active layer 114 is supplied with electricity to emit light, and the first nitride active layer 111 has a principle of emitting ultraviolet light to emit visible light.

Ultraviolet rays emitted from the second nitride active layer 114 effectively excites electrons from the first quantum wells 111W in the first nitride active layer 111 and excited electrons are recombined in the first quantum well 111W Coupled with holes, it can emit green light quantitatively.

Since the ultraviolet light energy is smaller than the energy band gap of the first quantum well 111B in the first nitride active layer 111 and larger than the energy band gap of the first quantum well 111W, 111W) and excites electrons in the first quantum wall 111B.

The energy of the excited electrons does not exceed the first quantum wall 111B and is confined in the first quantum well 111W quantitatively and effectively so that the electrons generated by the internal electric field formed by the lattice mismatch in the first nitride active layer 111 There is no leakage phenomenon of the light emitting layer, and excellent light emitting efficiency can be realized.

Therefore, according to the embodiment, the ultraviolet light emitting layer, which is the second nitride active layer 114, has an advantage that there is no decrease in luminous efficiency when the injection current is increased, and a visible light emitting layer excited by the ultraviolet light provided from the ultraviolet light emitting layer, The first nitride active layer 111, which is a light emitting layer, has excellent luminous efficiency because electrons are effectively restrained by the first quantum well 111W, thereby preventing leakage of electrons.

As a result, according to the embodiment, it is possible to provide an excellent green nitride semiconductor light emitting device which does not have a reduction in luminous efficiency even at a high injection current.

6 is a sectional view of the light emitting device 103 according to the third embodiment, and the third embodiment can adopt the technical features of the first embodiment or the second embodiment.

Third Embodiment The first electrode 140 may be in contact with the first conductive type semiconductor layer 112 through the first active layer 111 and the first conductive type semiconductor layer 112.

For example, the first electrode 140 may include a third penetrating electrode 142c passing through the first nitride active layer 111 and the first conductive semiconductor layer 112, and a third penetrating electrode 142c passing through the first penetrating electrode 142c. And a second insulating layer 152b surrounding the side surface.

In the case of the third embodiment, the second electrode 130 may have the same horizontal width as the ohmic layer 122 or the reflective layer 124.

Reference numerals and structures not described above will be described in the following manufacturing method.

Hereinafter, a method of manufacturing a light emitting device according to an embodiment will be described with reference to FIGS. 7 to 13, and technical features of the present invention will be described.

First, the first nitride active layer 111 can be formed on the substrate 105 as shown in FIG.

The substrate 105 may be formed of an insulating substrate or a conductive substrate. For example, the substrate 105 may be formed of at least one of a sapphire substrate (Al ₂ O ₃ ), SiC, GaAs, GaN, ZnO, Si, GaP, InP and Ge.

A buffer layer (not shown) may be formed on the substrate 105. The buffer layer may mitigate the lattice mismatch between the first nitride active layer 111 and the substrate 105. The material of the buffer layer may be a group III-V compound semiconductor such as GaN, InN, AlN, InGaN, AlGaN, InAlGaN , And AlInN.

As shown in FIG. 8, the first active layer 111 may include a first quantum wall 111B and a first quantum well 111W.

The first nitride active layer 111 may be formed of at least one of a multi quantum well (MQW) structure, a quantum-wire structure, and a quantum dot structure. For example, the first nitride active layer 111 is formed by implanting trimethyl gallium gas (TMGa), ammonia gas (NH ₃ ), nitrogen gas (N ₂ ), and trimethyl indium gas (TMIn) But is not limited thereto.

The first quantum well 111W and the first quantum wall 111B of the first active layer 111 are formed of InGaN / InGaN / InGaN, GaN / AlGaN, InAlGaN / GaN, GaAs (InGaAs) InGaP) / AlGaP, but the present invention is not limited thereto.

For example, the first nitride active layer 111 may be a light emitting layer capable of emitting green light of about 500 to 540 nm, and may be a multiple quantum well structure nitride semiconductor thin film layer formed on the basis of an InGaN quantum well and a GaN quantum wall. But is not limited thereto.

Next, as shown in FIG. 9, the first conductive semiconductor layer 112 and the second nitride active layer 114 may be formed on the first nitride active layer 111.

The first conductive semiconductor layer 112 may be formed of a semiconductor compound. Group 3-Group 5, Group 2-Group 6, and the like, and the first conductive type dopant may be doped. When the first conductive semiconductor layer 112 is an n-type semiconductor layer, the first conductive dopant may include Si, Ge, Sn, Se, and Te as an n-type dopant.

The first conductive semiconductor layer 112 may include 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 + . For example, the first conductive semiconductor layer 112 may be formed of one or more of GaN, InN, AlN, InGaN, AlGaN, InAlGaN, AlInN, AlGaAs, InGaAs, AlInGaAs, GaP, AlGaP, InGaP, AlInGaP, .

The n-type GaN layer may be formed on the first conductive semiconductor layer 112 using a chemical vapor deposition (CVD) method, molecular beam epitaxy (MBE), sputtering, or vapor phase epitaxy (HVPE) . The first conductive semiconductor layer 112 may be formed by depositing a silane containing an n-type impurity such as trimethyl gallium gas (TMGa), ammonia gas (NH ₃ ), nitrogen gas (N ₂ ) Gas (SiH ₄ ) may be implanted and formed.

In an embodiment, the second nitride active layer 114 may emit ultraviolet light.

For example, as shown in FIG. 10, the second nitride active layer 114 may include a second quantum wall 114B and a second quantum well 114W. For example, the second nitride active layer 114 may be a multi-quantum well structure nitride semiconductor thin film layer based on an InGaN quantum well and an AlGaN quantum well as a light emitting layer capable of emitting near UV at about 380 to 420 nm, It is not.

Next, as shown in FIG. 11, the second conductive semiconductor layer 116 is formed on the second nitride active layer 114.

The second conductive 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 semiconductor layer 116 may have a composition formula of In _x Al _y Ga _{1 -x- y} N (0? X? 1, 0? _Y? 1, 0? _X + And the like. When the second conductive semiconductor layer 116 is a p-type semiconductor layer, the second conductive dopant may include Mg, Zn, Ca, Sr, and Ba as p-type dopants.

The second conductive type semiconductor layer 116 is Bisei that the chamber comprises a p-type impurity such as trimethyl gallium gas (TMGa), ammonia gas (NH _3), nitrogen gas (N _2), and magnesium (Mg) butyl bicyclo The p-type GaN layer may be formed by implanting pentadienyl magnesium (EtCp ₂ Mg) {Mg (C ₂ H ₅ C ₅ H ₄ ) ₂ }, but the present invention is not limited thereto.

In an 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. Also, on the second conductive semiconductor layer 116, a semiconductor (e.g., an n-type semiconductor) (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.

Next, the ohmic layer 122 and the reflective layer 124 may be formed on the second conductive semiconductor layer 116.

The ohmic layer 122 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, ZnO, IrOx, AlGaO, AlGaO, AZO, ATO, GZO, IZO, Ni, Cr, Ti, Al, Rh, Pd, Ir, Ru, Mg, Zn, Pt, Au, Hf, NiO, RuOx / ITO, Ni / IrOx / And it is not limited to such a material.

The reflective layer 124 may be formed of a material excellent in reflectivity and excellent in electrical contact. For example, it may be formed of a metal or an alloy containing at least one of Ag, Ni, Al, Rh, Pd, Ir, Ru, Mg, Zn, Pt, Au and Hf. The reflective layer 124 may be formed of a multilayer structure using a metal or an alloy and a light transmitting conductive material such as IZO, IZTO, IAZO, IGZO, IGTO, AZO, or ATO. For example, IZO / Ni, AZO / Ag, IZO / Ag / Ni, AZO / Ag / Ni, or the like.

Next, the substrate 105 may be removed such that the first nitride active layer 111 is exposed, as shown in FIG. The substrate 105 may be removed using a high-power laser, or a chemical etching method may be used. In addition, the substrate 105 may be removed by physically grinding.

For example, in the laser lift-off method, energy is absorbed at the interface between the substrate 105 and the light emitting structure when a predetermined energy is applied at room temperature, and the bonding surface of the light emitting structure is thermally decomposed to separate the substrate 105 from the light emitting structure can do.

Thereafter, the exposed undoped semiconductor layer may be removed, but is not limited thereto.

Next, a trench T penetrating through the reflective layer 124, the ohmic layer 122, the second conductivity type semiconductor layer 116, and the second nitride active layer 114 is formed, and the trench T is formed on the side surface of the trench T The first insulating layer 152 can be formed.

13, a first penetrating electrode 142a filling the trench T is formed, and a lower electrode 144 is formed on the first penetrating electrode 142a to form a first electrode 140, Can be formed.

A second electrode 130 may be formed on the reflective layer 124.

According to the embodiment, in order to solve the problems of the conventional green nitride semiconductor light emitting device, the second nitride active layer 114, which is an ultraviolet light emitting layer, is provided and a first nitride active layer 111, which is a green light emitting layer, do. The second nitride active layer 114 is supplied with electricity to emit light, and the first nitride active layer 111 has a principle of emitting ultraviolet light to emit visible light.

Ultraviolet rays emitted from the second nitride active layer 114 effectively excites electrons from the first quantum wells 111W in the first nitride active layer 111 and excited electrons are recombined in the first quantum well 111W Coupled with holes, it can emit green light quantitatively.

Since the ultraviolet light energy is smaller than the energy band gap of the first quantum well 111B in the first nitride active layer 111 and larger than the energy band gap of the first quantum well 111W, 111W) and excites electrons in the first quantum wall 111B.

The energy of the excited electrons does not exceed the first quantum wall 111B and is confined in the first quantum well 111W quantitatively and effectively so that the electrons generated by the internal electric field formed by the lattice mismatch in the first nitride active layer 111 There is no leakage phenomenon of the light emitting layer, and excellent light emitting efficiency can be realized.

Therefore, according to the embodiment, the ultraviolet light emitting layer, which is the second nitride active layer 114, has an advantage that there is no decrease in luminous efficiency when the injection current is increased, and a visible light emitting layer excited by the ultraviolet light provided from the ultraviolet light emitting layer, The first nitride active layer 111, which is a light emitting layer, has excellent luminous efficiency because electrons are effectively restrained by the first quantum well 111W, thereby preventing leakage of electrons.

As a result, according to the embodiment, it is possible to provide an excellent green nitride semiconductor light emitting device which does not have a reduction in luminous efficiency even at a high injection current.

Embodiments provide a light emitting device capable of providing a high efficiency even under a high injection current by exciting a green light source of a second light emitting layer by providing a first light emitting layer having no decrease in light emitting quantum efficiency according to an increase in injection current, Device package and illumination system.

14 is a view illustrating a light emitting device package 200 to which a light emitting device according to an embodiment is applied.

Referring to FIG. 14, a light emitting device package according to an embodiment includes a body 205, first and second lead electrodes 213 and 214 disposed on the body 205, And a molding member 240 surrounding the light emitting device 100. The light emitting device 100 may include a light emitting device 100 that is provided on the first lead electrode 213 and the second lead electrode 214 and is electrically connected to the first lead electrode 213 and the second lead electrode 214, .

The body 205 may be formed of 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 first lead electrode 213 and the second lead electrode 214 are electrically isolated from each other and provide power to the light emitting device 100. [ The first lead electrode 213 and the second lead electrode 214 may increase the light efficiency by reflecting the light generated from the light emitting device 100. The heat generated from the light emitting device 100 To the outside.

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

The light emitting device 100 may be electrically connected to the first lead electrode 213 and the second lead electrode 214 by a wire, flip chip, or die bonding method.

The light emitting device 100 may be mounted on the second lead electrode 214 and connected to the first lead electrode 213 by the wire 230. However, the embodiment is not limited thereto.

The molding member 240 surrounds the light emitting device 100 to protect the light emitting device 100. In addition, the molding member 240 may include a phosphor (not shown) 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.

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

15, 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.

A first conductive semiconductor layer 112;
A first nitride active layer 111;
A second nitride active layer 114;
The second conductivity type semiconductor layer 116:
A first electrode 140; A second electrode 130;

Claims (8)

A first conductive semiconductor layer;
A first nitride active layer disposed on the first conductive semiconductor layer;
A second nitride active layer disposed under the first conductive semiconductor layer;
A second conductive semiconductor layer disposed under the second nitride active layer;
A first electrode electrically connected to the first conductive semiconductor layer; And
And a second electrode that is electromagnetically coupled to the second conductive type semiconductor layer. The method according to claim 1,
The second nitride active layer
A light emitting element that emits ultraviolet rays. 3. The method of claim 2,
And the first nitride active layer is excited by ultraviolet light emitted from the second nitride active layer to emit visible light. The method of claim 3,
The first nitride active layer
And the second active layer is excited by ultraviolet rays emitted from the second nitride active layer to emit green light. 5. The method according to any one of claims 1 to 4,
The first electrode
And a second conductive semiconductor layer formed on the first conductive semiconductor layer. 6. The method of claim 5,
Further comprising an ohmic layer and a reflective layer disposed below the second conductive type semiconductor layer,
The first electrode
And a first penetrating electrode penetrating the second conductivity type semiconductor layer, the ohmic layer, and the reflective layer,
And a first insulating layer surrounding the first penetrating electrode. 5. The method according to any one of claims 1 to 4,
The first electrode
And the first conductive semiconductor layer is in contact with the first nitride active layer and the first conductive semiconductor layer. An illumination system comprising a light emitting unit comprising the light emitting element according to any one of claims 1 to 4.

Images