KR20170064296A - Light emitting device and lighting apparatus - Google Patents

Abstract

Embodiments relate to a light emitting device, a method of manufacturing a light emitting device, a light emitting device package, and a lighting device.
The light emitting device according to the embodiment includes a substrate 100 having a plurality of heat dissipating pillars 100P spaced apart from each other by a plurality of recesses R formed in the top surface direction from the bottom surface; A first conductive semiconductor layer 112 on the substrate 100, an active layer 114 on the first conductive semiconductor layer 112, and a second conductive semiconductor layer 116 on the active layer 114, (110); A first electrode 131 disposed on an upper surface of the first conductivity type semiconductor layer 112 exposed by a first region M2 in which the second conductivity type semiconductor layer and the active layer are partially removed; A second electrode 132 disposed on the second conductive semiconductor layer 116; And a heat dissipation layer (100H) disposed on the heat dissipation column (100P) of the substrate.

Description

TECHNICAL FIELD [0001] The present invention relates to a light emitting device,

Embodiments relate to a light emitting device, a method of manufacturing a light emitting device, a light emitting device package, and a lighting device.

A light emitting device (LED) can be formed by combining a group III-V element or a group II-VI element in the periodic table with a pn junction diode, in which electric energy is converted into light energy, So that various colors can be realized.

For example, nitride semiconductors have received great interest in the development of optical devices and high power electronic devices due to their thermal stability and wide band gap energy. Particularly, a blue light emitting element, a green light emitting element, an ultraviolet (UV) light emitting element, and a red (RED) light emitting element using a nitride semiconductor are commercially available and widely used.

On the other hand, from the conventional LED technology to the LED device for high power illumination, the thermal leakage current due to the thermal instability inside the LED device increases and thus the light efficiency deteriorates.

1 is a cross-sectional view of a conventional light emitting device.

In the conventional light emitting device, an n-type semiconductor layer 22, an active layer 24, and an epi layer 20 including a p-type semiconductor layer 26 are sequentially stacked on a sapphire substrate 10, The p-contact 32 is disposed on the n-contact 31 and the p-type semiconductor layer 26 on the substrate 22.

2 is a photograph of an emission pattern analysis of a conventional light emitting device.

According to the related art, the LED epitaxial layer 20 is formed on the sapphire substrate 10 having a low thermal conductivity by MOCVD or the like, thereby lowering heat radiation efficiency through the substrate 10.

Also, in the prior art, when the LED chip is injected into the active layer 24 through the n-contact 31 and the p-contact 32, the n-type semiconductor having a high parasitic resistance A voltage drop occurs in the current path due to the influence of the layer 22 and the p-type semiconductor layer 26 and a band switching (a voltage drop) occurs in the current path due to the non-emission recombination such as auger recombination Band Transition), there is a problem that the luminous efficiency is lowered.

Further, according to the related art, the current crowding is deepened in the boundary portion M1 between the p-type semiconductor layer 26 and the n-type semiconductor layer 22, which is the mesa region of the LED chip, Therefore, there is a problem that the thermal stability of the mesa region M1 of the LED chip is deteriorated and the electrical characteristics and luminous efficiency of the light emitting device as a whole are lowered.

Embodiments provide a light emitting device having excellent heat dissipation efficiency, a method of manufacturing a light emitting device, a light emitting device package, and a lighting device.

Also, embodiments of the present invention provide a light emitting device, a method of manufacturing a light emitting device, a light emitting device package, and a lighting device capable of improving the optical characteristics of the light emitting device by achieving thermal stability.

The light emitting device according to the embodiment includes a substrate 100 having a plurality of heat dissipating pillars 100P spaced apart from each other by a plurality of recesses R formed in the top surface direction from the bottom surface; A first conductive semiconductor layer 112 on the substrate 100, an active layer 114 on the first conductive semiconductor layer 112, and a second conductive semiconductor layer 116 on the active layer 114, (110); A first electrode 131 disposed on an upper surface of the first conductivity type semiconductor layer 112 exposed by a first region M2 in which the second conductivity type semiconductor layer and the active layer are partially removed; A second electrode 132 disposed on the second conductive semiconductor layer 116; And a heat dissipation layer (100H) disposed on the heat dissipation column (100P) of the substrate.

The light emitting device according to the embodiment includes a substrate 100 having a plurality of heat dissipating pillars 100P spaced apart from each other by a plurality of recesses R formed in the top surface direction from the bottom surface; A first conductive semiconductor layer 112 on the substrate 100, an active layer 114 on the first conductive semiconductor layer 112, and a second conductive semiconductor layer 116 on the active layer 114, (110); A first electrode 131 disposed on an upper surface of the first conductivity type semiconductor layer 112 exposed by a first region M2 in which the second conductivity type semiconductor layer and the active layer are partially removed; And a heat dissipation layer (100H) disposed on the heat dissipation column (100P) of the substrate, wherein the recess (R) of the substrate has a first recess (R1) overlapping the first region (M2) And a second recess R2 that does not overlap the first region M2 and the horizontal width of the first recess R1 is different from the horizontal width of the second recess R2 .

The lighting apparatus according to the embodiment may include a light emitting unit having the light emitting element.

The embodiment employs a substrate having a high thermal conductivity. The substrate is processed into a column shape by providing a plurality of recesses on the bottom surface of the substrate, and a high heat conductive heat dissipation layer is formed on the column to locally stagnate inside the LED chip A light emitting device package, and a lighting device having excellent heat dissipation efficiency by efficiently discharging the heat generated by the light emitting device.

In addition, the embodiment can reduce the thermal leakage current by making the thermal stability on the current path inside the LED chip by the above structure.

In addition, the embodiment can concentrate the heat-radiating column and the heat-radiating layer in the mesa region of the LED chip where the current crowding problem occurs, thereby improving the optical characteristics of the light-emitting device by achieving thermal stability of the device.

1 is a cross-sectional view of a conventional light emitting device;
2 is a thermal analysis photograph of a light emitting device according to the prior art.
3 is a cross-sectional view of a light emitting device according to the first embodiment;
4 is a sectional view of a light emitting device according to a second embodiment;
5 is a photograph of the light emitting device according to the second embodiment.
6A to 8B are characteristic comparison diagrams of light emitting devices according to the prior art and the embodiment.
9 to 15 are cross-sectional views illustrating a manufacturing process of a light emitting device according to an embodiment.
16 is a cross-sectional view of a light emitting device package according to an embodiment.
17 is a perspective view of a lighting apparatus 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.

(Example)

3 is a sectional view of the light emitting device 101 according to the first embodiment.

The light emitting device 101 according to the first embodiment may include a substrate 100, a light emitting structure 110, a first electrode 131, and a second electrode 132.

For example, the light emitting device 101 according to the embodiment includes a substrate 100, a first conductive semiconductor layer 112 on the substrate 100, and a second conductive semiconductor layer 112 on the first conductive semiconductor layer 112, The light emitting structure 110 including the second conductivity type semiconductor layer 116 on the active layer 114 and the second conductivity type semiconductor layer 116 and the active layer 114, The first electrode 131 is formed on the upper surface of the first conductive semiconductor layer 112 exposed by the first region M2 and the second electrode 132 is formed on the second conductive type semiconductor layer 116 .

The substrate 100 may include a plurality of heat dissipation pillars 100P separated from a bottom surface by a plurality of recesses R formed in the direction of the light emitting structure 110 and a plurality of heat dissipation pillars 100P And a heat dissipation layer 100H formed thereon.

According to the related art, since the LED epitaxial layer is formed on the sapphire substrate having low thermal conductivity, the heat radiation efficiency through the substrate is low, so that the heat dissipation property is lowered and the electrical reliability is lowered.

In an embodiment, the substrate 100 may be a substrate with a high thermal conductivity. For example, the embodiment of the substrate 100 are an Si substrate, GaN substrate, GaAs substrate, a Ga substrate, GaP substrate, InP substrate, a SiC substrate, a ZnO substrate, a Ge substrate, and Ga ₂ 0 ₃ Substrate, but is not limited thereto.

The embodiment can improve the electrical characteristics and the light emitting characteristics by improving the heat radiation efficiency of the light emitting element by employing the substrate having high thermal conductivity.

The substrate 100 may include a plurality of heat radiating columns 100P spaced apart from a bottom surface thereof by a plurality of recesses R formed in the direction of the light emitting structure 110. [

According to the embodiment, by providing a plurality of heat radiating column (100P) structures spaced apart from the recess R, the heat radiation efficiency can be further improved by increasing the contact surface area of the substrate 100 with the outside.

For example, when the light emitting device package is mounted, the pasting material is extended in various places in the recess to widen the contact area and contact with the heat dissipating post, thereby improving the heat dissipating efficiency.

And may be penetrated from the bottom surface to the top surface of the substrate 100 by the recesses R in the embodiment. Accordingly, the heat emitted from the light emitting structure 110 can be extracted to the outside more efficiently through the heat dissipation layer 100H formed outside or after the light emitting device chip.

There is a structure in which a recess is formed in a part of the bottom surface of the substrate in the prior art. However, these structures have a small effect on the increase in heat radiation efficiency by locally forming the recess on the bottom surface of the substrate, It can be considered that there is a limit to be taken into consideration of the point that it is directly discharged through the heat dissipation layer.

The embodiment may include a heat dissipation layer 100H formed on the heat dissipation column 100P. The heat dissipation layer 100H may have higher thermal conductivity than the heat dissipation column 100P. For example, the heat dissipation layer 100H may include a metal heat dissipation layer. For example, the heat dissipation layer 100H may include at least one of Ag, Al, Ti, and Cr, but is not limited thereto.

According to the embodiment, the heat dissipation efficiency is maximized by further forming the heat dissipation layer 100H on the heat dissipation column 100P of the substrate having high thermal conductivity, so that the electrical reliability of the light emitting element can be increased, The characteristics can also be improved.

The heat dissipation layer 100H may be in direct contact with the light emitting structure 110 or between the substrate 100 and the light emitting structure 110 when the recess R penetrates from the bottom surface to the top surface of the substrate 100. [ The heat generated in the light emitting structure 110 can be more efficiently extracted to the outside through the heat dissipation layer 100H.

Meanwhile, when the light emitting device 101 according to the embodiment is die-bonded to a predetermined light emitting device package body, the pasting material may be an insulating material with good heat radiation efficiency. Accordingly, even if the heat dissipation layer 100H is electrically connected to the light emitting structure 110 in the light emitting device according to the embodiment, the conduction between the light emitting structure 110 and the lead frame (not shown) on the package body is prevented by the insulating paste material Can be blocked.

Also, in the embodiment, the heat dissipation layer 100H may include a reflective layer. For example, the heat dissipation layer 100H may include one or more of Ag, Ni, Cr, Ti, Al, Rh, Pd, Ir, Ru, Mg, Zn, Pt, The light extraction efficiency can be improved.

In the embodiment, the height H of the heat radiating column 100P itself may be about 2 to 4 times the pitch P between the heat radiating columns 100P. If the range is less than 2 times, the mechanical stability is low, and there is a risk of occurrence of mechanical crack due to external impact. If the range is more than 4 times, there is a risk that a chip level heat sink ), The heat radiation efficiency may be lowered because the heat flux is less than the heat flux emission area for achieving sufficient thermal stability.

In an embodiment, the pitch (P) between the heat radiating pillars 100P may be about 50 mu m to about 100 mu m. If the spacing P between the heat radiating posts 100P is less than 50 mu m, the heat radiation efficiency may be lowered because the radiating sink of the chip unit is smaller than the heat flux radiating area for achieving sufficient thermal stability, When the distance P between the heat radiating pillars 100P is more than 100 mu m, the mechanical bonding stability due to the paste between the light emitting element chip die and the lead frame is low in the process for forming the light emitting device package, There is a risk of cracking.

In an embodiment, the height H of the heat radiating column 100P of the substrate may be about 100 mu m to about 200 mu m. If the height H of the heat dissipation column 100P is less than 100 mu m, the heat dissipation efficiency of the heat dissipation layer 100H can not be sufficiently secured. If the height H of the heat dissipation column 100P exceeds 200 mu m, Mechanical Robust) is difficult to secure and there is a risk of cracking.

In an embodiment, the horizontal width W of the heat radiating column 100P may be about 10 [mu] m to about 20 [mu] m. When the horizontal width W of the heat dissipation column 100P is less than 10 mu m, there is a risk of cracking due to low mechanical bonding stability between the light emitting device chip and the lead frame in the packaging process, When the thickness exceeds 20 탆, the heat dissipation efficiency may be lowered due to an increase in the remaining area of the substrate 100, which has a lower thermal conductivity than the heat dissipation layer 100H.

FIG. 4 is a cross-sectional view of the light emitting device 102 according to the second embodiment, and FIG. 5 is an analysis photograph of the light emitting device 102 according to the second embodiment.

According to the conventional art, there is a problem that the current crowding is intensified in the mesa region which is a boundary portion between the p-type semiconductor layer and the n-type semiconductor layer according to the emission pattern.

The light emitting device according to the embodiment may include a first region M2 in which the second conductivity type semiconductor layer 116 and the active layer 114 are partially removed and the first region M2 exposed by the first region M2 The first electrode 131 may be disposed on the upper surface of the conductive semiconductor layer 112.

The recesses R formed in the substrate in the second embodiment are divided into a first recess R1 overlapping the first region M2 and a second recess R2 overlapping the first region M2 ). The horizontal widths of the first recess R1 and the second recess R2 may be different from each other.

For example, in an embodiment, the first horizontal width of the first recess R1 may be smaller than the second horizontal width of the second recess R2.

Also, in an embodiment, the recess (R) may include a third recess (R) in the outer region of the chip. The horizontal width of the third recess R3 may be larger than the horizontal width of the second recess R2.

Accordingly, as the distance from the first region M2 increases, the horizontal width of the recess may be formed to be wide considering the heat distribution, but the present invention is not limited thereto.

5, according to the embodiment, the first region M2 in which the second conductivity type semiconductor layer 116 and the active layer 114 are partially removed, that is, the heat radiation layer 100H in a so-called mesa region, The thermal stability of the light emitting device can be further improved.

In an exemplary embodiment, the first conductive semiconductor layer 112 may include a protrusion 112P contacting the heat dissipation column 100P. Accordingly, the heat generated in the light emitting structure 110 can be efficiently emitted by the heat dissipation layer 100H directly contacting the protrusion 112P.

The bottom surface of the protrusion 112P of the first conductivity type semiconductor layer may be disposed lower than the top surface of the recess R. Further, the upper surface of the heat radiating column 100P may be disposed lower than the uppermost surface of the recess R. Accordingly, the heat dissipation efficiency can be increased by widening the area of the heat dissipation layer (100H) in contact with the first conductivity type semiconductor layer (112).

According to the embodiment, a substrate having a high thermal conductivity is employed, a plurality of recesses are provided on the bottom surface of the substrate to process the substrate into a column shape, and a high heat conductive heat dissipation layer is formed on the heat dissipation column, It is possible to provide a light emitting device having excellent heat dissipation efficiency by effectively discharging locally stagnated heat.

In addition, the embodiment can reduce the thermal leakage current by making the thermal stability on the current path inside the LED chip by the above structure.

In addition, the embodiment can concentrate the heat-radiating column and the heat-radiating layer in the mesa region of the LED chip where the current crowding problem occurs, thereby improving the optical characteristics of the light-emitting device by achieving thermal stability of the device.

Hereinafter, the improved effects of the light emitting device according to the embodiment will be described with reference to FIGS. 6A to 8B.

6A and 6B are electric field diagram diagrams of a light emitting device according to the related art and embodiments, respectively.

According to the embodiment, when a plurality of recesses are formed in the substrate, an electric field due to lattice mismatching between the substrate and the light emitting structure can be eliminated. This effect is an effect that is not anticipated by the recess or etch structure that forms in only a portion of the bottom surface of the substrate in the prior art.

That is, as shown in FIG. 6B, the electric field distribution A2 according to the embodiment is different from the electric field distribution A1 in the prior art (see FIG. 6A) Field can be reduced or eliminated to improve the efficiency of radial recombination.

7A and 7B are energy band-gap diagrams of the light emitting device according to the related art and the embodiments, respectively.

According to the embodiment, when a plurality of recesses are formed in the substrate, the polarization of the active layer due to lattice mismatching between the substrate and the light emitting structure can be relaxed, thereby alleviating the distortion of the band gap of the active layer. This effect is also an effect that is not anticipated by the recess or etch structure that forms in only a portion of the bottom surface of the substrate in the prior art.

Specifically, as shown in FIG. 7B, the band gap diagram B2 of the active layer region according to the embodiment is compared with the band gap diagram B1 of the prior art (FIG. 7A), the polarity due to lattice mismatch between the substrate and the epitaxial ) Can be relaxed to improve the radiative recombination efficiency.

8A and 8B are emission intensity spectra of the light emitting device according to the related art and the embodiments, respectively.

Compared with the prior art light intensity spectrum C1 (FIG. 8A), when the structure according to the embodiment is provided, the electric field existing in the epi region is reduced and the polarity is reduced to improve the radiant recombination efficiency, The emission intensity (C2) can be further increased.

Hereinafter, a method of manufacturing a light emitting device according to an embodiment will be described with reference to FIGS. 9 to 15. FIG. In the following description of the manufacturing method, the light emitting device according to the second embodiment will be described as a reference, but the manufacturing method is not limited thereto.

First, a substrate 100 is prepared as shown in FIG. The substrate 100 may be a substrate having a high thermal conductivity. For example, the embodiment of the substrate 100 are an Si substrate, GaN substrate, GaAs substrate, a Ga substrate, GaP substrate, InP substrate, a SiC substrate, a ZnO substrate, a Ge substrate, and Ga ₂ 0 ₃ Substrate, but is not limited thereto.

The embodiment can improve the electrical characteristics and the light emitting characteristics by improving the heat radiation efficiency of the light emitting element by employing the substrate having high thermal conductivity. The substrate 100 may be wet-cleaned to remove impurities on the surface.

A buffer layer (not shown) may be formed on the substrate 100. The buffer layer may mitigate lattice mismatch between the light emitting structure 110 and the substrate 100 formed thereafter.

The buffer layer may be formed of at least one of Group III-V compound semiconductor such as GaN, InN, AlN, InGaN, AlGaN, InAlGaN, and AlInN. An undoped semiconductor layer (not shown) may be formed on the buffer layer, but the present invention is not limited thereto.

Next, a light emitting structure 110 including a first conductive semiconductor layer 112, an active layer 114, and a second conductive semiconductor layer 116 may be formed on the substrate 100 or the buffer layer .

The first conductive semiconductor layer 112 may be formed of a compound semiconductor such as a Group 3-Group-5, Group-6, or the like, and may be doped with a first conductive dopant.

For example, when the first conductive semiconductor layer 112 is an n-type semiconductor layer, the n-type dopant may include Si, Ge, Sn, Se, and Te.

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 first conductive semiconductor layer 112 may be formed using a chemical vapor deposition (CVD) method, a molecular beam epitaxy (MBE) method, a sputtering method, or a vapor phase epitaxy (HVPE) method. .

Next, the active layer 114 may be formed on the first conductive semiconductor layer 112. The active layer 114 may include electrons injected through the first conductivity type semiconductor layer 112 and second Holes injected through the conductive semiconductor layer 116 are mutually opposed to each other to emit light having energy determined by the energy band inherent in the active layer (light emitting layer) material.

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 quantum well / quantum wall structure. For example, the active layer 114 may be formed of any one or more pairs of InGaN / GaN, InGaN / InGaN, GaN / AlGaN, InAlGaN / GaN, GaAs / AlGaAs, InGaP / AlGaP and GaP / AlGaP. It does not.

Next, an electron blocking layer (not shown) is formed on the active layer 114 to serve as electron blocking and cladding of the active layer 114, thereby improving the luminous efficiency.

For example, the electron blocking layer may be formed of an Al _x In _y Ga _(1-xy) N (0? _{X ? 1, 0? Y ? 1} ) semiconductor, Lt; RTI ID = 0.0 > bandgap < / RTI > In the embodiment, the electron blocking layer can effectively block the electrons that are ion-implanted into the p-type and overflow, and increase the hole injection efficiency.

Next, a second conductive type semiconductor layer 116 may be formed on the electron blocking layer.

The second conductive semiconductor layer 116 may be formed of a semiconductor compound. For example, the second conductive semiconductor layer 116 may be formed of a compound semiconductor such as a Group III-V, a Group II-VI, or the like, and may be doped with a second conductive dopant.

The second conductive semiconductor layer 116 may be a Group III-V compound semiconductor doped with a second conductive dopant, for example, In _x Al _y Ga _{1 -x- y} N (0? X? 1, 0? _Y 1, 0? X + y? 1). 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, as shown in FIG. 10, a part of the upper conductive semiconductor layer 112 may be partially removed so that the first conductive semiconductor layer 112 is partially exposed. For example, portions of the second conductive semiconductor layer 116, the electron blocking layer, and the active layer 114 may be removed, and a portion of the upper surface of the first conductive semiconductor layer 112 may be removed as the case may be . Such a process may be performed by wet etching or dry etching, but is not limited thereto.

Thus, according to the embodiment, the second conductivity type semiconductor layer 116 and the active layer 114 may be partially removed.

Next, referring to FIG. 12, a current blocking layer (not shown) may be formed at a position where the second electrode 152 is to be formed. The current blocking layer may include a non-conductive region, a first conductive type ion-implanted layer, a first conductive type diffusion layer, an insulator, an amorphous region, and the like.

Next, a light-transmitting electrode layer (not shown) may be formed on the second conductivity type semiconductor layer 116 on which the current blocking layer is formed. The light-transmitting electrode layer may include an ohmic layer, and may be formed by laminating a single metal, a metal alloy, a metal oxide, or the like so as to efficiently inject holes.

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

Thereafter, a passivation layer (not shown) may be formed on the side of the light emitting structure 110 and a part of the light transmitting electrode layer using an insulating layer or the like. The passivation layer may expose a region where the first electrode 151 is to be formed.

Next, a second electrode 152 may be formed on the light-transmitting electrode layer so as to overlap with the current blocking layer, and a first electrode 151 may be formed on the exposed first conductive semiconductor layer 112 have.

The first electrode 151 or the second electrode 152 may be formed of one selected from the group consisting of Ti, Cr, Ni, Al, Pt, Au, Molybdenum (Mo), but the present invention is not limited thereto.

Next, as shown in FIG. 12, a plurality of heat radiating pillars 100P spaced apart from a bottom surface of the substrate 100 by a plurality of recesses R formed in the direction of the light emitting structure 110 are formed can do.

The method of forming the heat radiating column 100P on the substrate 100 may be performed by an etching method of the substrate 100. [

For example, in an embodiment, a recess (R) may be formed on the substrate 100 by etching the substrate 100 in a striped or lattice pattern using a reactive ion etching (RIE) The heat radiating column 100P can be formed.

This is because, in the prior art, since the LED epitaxial layer is formed on the sapphire substrate having a low thermal conductivity, the heat radiation efficiency through the substrate is low, so that the heat dissipation property is lowered and the electrical reliability is lowered. It is part of the process.

FIG. 13 is a cross-sectional photograph in which recesses R are formed in the substrate 100 according to the embodiment, and FIG. 14 is an example of a mask pattern for etching the substrate 100 of the light emitting device according to the embodiment.

12, the embodiment has a plurality of heat radiating column 100P structures spaced apart by the recesses R, so that the heat radiating efficiency can be further improved by increasing the contact surface area of the substrate 100 with the outside .

For example, when the light emitting device package is mounted, the heat dissipation efficiency can be improved by expanding the paste material in various places in the recess R and coming into contact with the heat radiating pillar.

And may be penetrated from the bottom surface to the top surface of the substrate 100 by the recesses R in the embodiment. Accordingly, the heat emitted from the light emitting structure 110 can be extracted to the outside more efficiently through the heat dissipation layer 100H formed outside or after the light emitting device chip.

In the embodiment, the height H of the heat radiating column 100P itself may be about 2 to 4 times the pitch P between the heat radiating columns 100P. If the range is less than two times, the mechanical stability may be low, and if it is more than four times, the heat dissipation efficiency may be deteriorated.

In an embodiment, the pitch (P) between the heat radiating pillars 100P may be about 50 mu m to about 100 mu m. If the spacing P between the heat radiating pillars 100P is less than 50 mu m, the heat radiation efficiency may be lowered, and when the interval is 100 mu m or more, the mechanical stability may be deteriorated.

In an embodiment, the height H of the heat radiating column 100P of the substrate may be about 100 mu m to about 200 mu m. If the height H of the heat radiating column 100P is less than 100 mu m, the heat radiation efficiency may be lowered. If the height H is 200 mu m or more, the mechanical strength may be low.

In an embodiment, the horizontal width W of the heat radiating column 100P may be about 10 [mu] m to about 20 [mu] m. When the horizontal width W of the heat radiating column 100P is less than 10 mu m, cracking may occur due to low mechanical strength, and heat radiation efficiency may be lowered when the horizontal width W exceeds 20 mu m.

The recess R formed in the substrate in the second embodiment includes a first recess R1 overlapping the first region M2 in which the second conductive semiconductor layer 116 and the active layer 114 are partially removed, And a second recess R2 that does not overlap with the first region M2. The horizontal widths of the first recess R1 and the second recess R2 may be different from each other. For example, in an embodiment, the first horizontal width W of the first recess R1 may be smaller than the second horizontal width W of the second recess R2.

According to the embodiment, the device thermal stability of the light emitting device can be improved by concentrating the first region M2 in which the second conductivity type semiconductor layer 116 and the active layer 114 are partially removed, that is, the heat dissipation layer 100H in the so- And more.

Embodiments can improve the optical characteristics of the light emitting device by concentrating the heat dissipation pillars and the heat dissipation layer in the mesa region of the LED chip in which the current crowding problem occurs, thereby achieving thermal stability of the device.

Also, in an embodiment, the recess (R) may include a third recess (R) in the outer region of the chip. The horizontal width of the third recess R3 may be larger than the horizontal width of the second recess R2. Accordingly, as the distance from the first region M2 increases, the horizontal width of the recess may be formed to be wide considering the heat distribution, but the present invention is not limited thereto.

Next, as shown in FIG. 15, a heat dissipation layer 100H may be formed on the heat dissipation column 100P to manufacture a light emitting device according to an embodiment. The heat dissipation layer may have higher thermal conductivity than the heat dissipation column. For example, the heat dissipation layer 100H may include a metal heat dissipation layer. For example, the heat dissipation layer 100H may include at least one of Ag, Al, Ti, and Cr, and may be formed by a deposition process, but the present invention is not limited thereto.

According to the embodiment, the heat dissipation efficiency is maximized by further forming the heat dissipation layer 100H on the heat dissipation column 100P of the substrate having high thermal conductivity, so that the electrical reliability of the light emitting element can be increased, The characteristics can also be improved.

The heat dissipation layer 100H may be in direct contact with the light emitting structure 110 or between the substrate 100 and the light emitting structure 110 when the recess R penetrates from the bottom surface to the top surface of the substrate 100. [ The heat generated in the light emitting structure 110 can be more efficiently extracted to the outside through the heat dissipation layer 100H.

In an embodiment, the heat dissipation layer 100H may include a reflective layer. For example, the heat dissipation layer 100H may include one or more of Ag, Ni, Cr, Ti, Al, Rh, Pd, Ir, Ru, Mg, Zn, Pt, The light extraction efficiency can be improved.

In an embodiment, the heat dissipation layer 100H may be formed by deposition from about 1 μm to about 2 μm, but the present invention is not limited thereto.

A plurality of light emitting devices according to the embodiments may be arrayed on a substrate in the form of a package, 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.

16 is a cross-sectional view of a light emitting device package 200 provided with a light emitting device according to an embodiment.

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 light emitting device 100 disposed on the first electrode layer 213 and electrically connected to the third electrode layer 213 and the fourth electrode layer 214 and a molding member 230 surrounding the light emitting device 101, . ≪ / RTI >

The third electrode layer 213 and the fourth electrode layer 214 are electrically isolated from each other and provide power to the light emitting device 100. The third electrode layer 213 and the fourth electrode layer 214 may function to increase the light efficiency by reflecting the light generated from the light emitting device 101, And may serve to discharge heat to the outside.

The light emitting device 101 may be electrically connected to the third electrode layer 213 and / or the fourth electrode layer 214 by a wire, flip chip, or die bonding method.

The light emitting device 101 according to the embodiment may be a light emitting device according to the first embodiment, but is not limited thereto, and may be a light emitting device according to the second embodiment.

In the die bonding of the light emitting device 101 according to the embodiment, the pasting material has good heat radiation efficiency, but an insulating material can be employed. Accordingly, even if the heat dissipation layer 100H is electrically connected to the light emitting structure 110 in the light emitting device according to the embodiment, the current blocking between the light emitting structure 110 and the third electrode layer 213 is blocked by the insulating paste material An electrical short may not occur.

The light emitting device according to the embodiment may 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.

17 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.

The substrate 100, the recess R, the pillar 100P, the heat dissipation layer 100H,
The first conductive semiconductor layer 112, the active layer 114, the second conductive semiconductor layer 116,
The first region M2, the first electrode 131, the second electrode 132,

Claims (17)

A substrate having a plurality of heat dissipating pillars spaced apart from each other by a plurality of recesses formed in the top surface direction at the bottom surface;
A light emitting structure including a first conductive semiconductor layer on an upper surface of the substrate, an active layer on the first conductive semiconductor layer, and a second conductive semiconductor layer on the active layer;
A first electrode disposed on an upper surface of the first conductive semiconductor layer exposed by a first region in which the second conductive semiconductor layer and the active layer are partially removed;
A second electrode disposed on the second conductive type semiconductor layer; And
And a heat dissipation layer disposed on the heat dissipation column of the substrate. The method according to claim 1,
The recess
The light emitting element being formed in a direction from the bottom surface of the substrate toward the light emitting structure. 3. The method of claim 2,
The substrate being penetrated by the recess,
Wherein the heat dissipation layer is in contact with a bottom surface of the light emitting structure. The method according to claim 1,
The heat-
And the thermal conductivity is higher than that of the heat radiating column. The method according to claim 1,
The heat-
A light emitting device comprising a metal heat conduction layer. The method according to claim 1,
The heat-
And a reflective layer. The method according to claim 1,
The spacing (pitch) between the heat-
50 to 100 占 퐉. The method according to claim 1,
The height of the heat-
(P) between the heat-dissipating pillars. A substrate having a plurality of heat dissipating pillars spaced apart from each other by a plurality of recesses formed in the top surface direction at the bottom surface;
A light emitting structure including a first conductive semiconductor layer on an upper surface of the substrate, an active layer on the first conductive semiconductor layer, and a second conductive semiconductor layer on the active layer;
A first electrode disposed on an upper surface of the first conductive semiconductor layer exposed by a first region in which the second conductive semiconductor layer and the active layer are partially removed; And
And a heat dissipation layer disposed on the heat dissipation column of the substrate,
The recess of the substrate,
A first recess overlapping the first region,
And a second recess that does not overlap the first region,
Wherein a horizontal width of the first recess is different from a horizontal width of the second recess. 10. The method of claim 9,
Wherein a horizontal width of the first recess is smaller than a horizontal width of the second recess. 10. The method of claim 9,
The first conductivity type semiconductor layer
And a protrusion that is in contact with the heat dissipation column. 12. The method of claim 11,
The bottom surface of the protrusion of the first conductivity type semiconductor layer
And is disposed lower than the top surface of the recess. 12. The method of claim 11,
The upper surface of the heat-
And is disposed lower than the top surface of the recess. 10. The method of claim 9,
The substrate being penetrated by the recess,
Wherein the heat dissipation layer is in contact with a bottom surface of the light emitting structure. 11. The method of claim 10,
The recess
Further comprising a third recess in an outer region of the substrate,
Wherein a horizontal width of the third recess is larger than a horizontal width of the second recess. 10. The method of claim 9,
The horizontal width of the recess
And the horizontal width increases as the distance from the first region increases. A lighting device comprising a light-emitting unit comprising the light-emitting element according to any one of claims 1 to 16.

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