KR102075574B1 - Light emitting device, method for fabricating the same and lighting system - Google Patents

Abstract

Embodiments relate to a light emitting device, a method of manufacturing the light emitting device, a light emitting device package and an illumination system.
The light emitting device according to the embodiment includes a substrate 70; A second conductivity type semiconductor layer 13 on the substrate 70; An active layer 12 on the second conductive semiconductor layer 13; A first conductivity type semiconductor layer 11 on the active layer 12; And light extraction nanopatterns 25 having different widths between upper and lower portions on the first conductivity-type semiconductor layer 11.

Description

LIGHT EMITTING DEVICE, METHOD FOR FABRICATING THE SAME AND LIGHTING SYSTEM

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

Light Emitting Device is a pn junction diode that converts electrical energy into light energy. It is based on compound semiconductors such as Group III and Group V on the periodic table, and various colors can be realized by controlling the composition ratio. .

When the forward voltage is applied, the n-layer electrons and the p-layer holes combine to emit energy corresponding to the bandgap energy of the conduction band and the valence band. Is mainly emitted in the form of heat or light, and emits light in the form of light emitting elements.

The light emitting device may be classified into a horizontal type light emitting device and a vertical type light emitting device according to the position of the electrode layer.

The light emitting device has a long life, low power consumption and environmentally-friendly advantages compared to conventional lighting devices such as fluorescent lamps and incandescent lamps, and is attracting attention as a future light source for lighting and is currently used as a light source in various fields.

In particular, nitride-based light emitting diodes having a wide bandgap can emit light in the green, blue, and near-ultraviolet region, so that their application fields, such as LCD and mobile phone backlights, automotive lighting, traffic signals, and general lighting, are greatly expanded. There is a trend.

However, nitride-based light emitting diodes are not sufficiently improved to meet such demands.

For example, the performance of a light emitting diode is largely determined by the internal quantum efficiency depending on how many photons are injected and how much photons can be emitted to the outside of the light emitting diode device. .

Among the current light emitting device technology, there is an attempt to improve the external light extraction efficiency, but technically and effectively, there is insufficient point to improve the light extraction efficiency.

Embodiments provide a light emitting device, a method of manufacturing a light emitting device, a light emitting device package, and an illumination system that can significantly increase light extraction performance of a light emitting diode.

The light emitting device according to the embodiment includes a substrate 70; A second conductivity type semiconductor layer 13 on the substrate 70; An active layer 12 on the second conductive semiconductor layer 13; A first conductivity type semiconductor layer 11 on the active layer 12; And light extraction nanopatterns 25 and 27 having different widths between upper and lower portions on the first conductivity type semiconductor layer 11.

In addition, the manufacturing method of the light emitting device according to the embodiment comprises the steps of preparing a growth substrate (5); Forming a nano printing pattern (22) on the growth substrate (5); Forming a light emitting structure (10) including a first conductivity type semiconductor layer, an active layer, and a second conductivity type semiconductor layer on the growth substrate (5) on which the nano printing pattern (22) is formed; Removing the growth substrate (5) from the light emitting structure (10); And removing the nanoprinting pattern 22 to form light extraction nanopatterns 25 and 27 on the light emitting structure 10.

In addition, the manufacturing method of the light emitting device according to the embodiment comprises the steps of preparing a growth substrate (5); Forming a light scattering nanopattern (23, 24) on the growth substrate (5); Forming a light emitting structure (10) including a first conductivity type semiconductor layer, an active layer, and a second conductivity type semiconductor layer on the growth substrate (5) on which the light scattering nanopatterns (23, 24) are formed; And removing the growth substrate 5 from the light emitting structure 10 to form light extraction nanopatterns 25 and 27 and light scattering nanopatterns 23 and 24 on the light emitting structure 10. can do.

In addition, the lighting system according to the embodiment may include a lighting unit having the light emitting device.

According to the light emitting device, the manufacturing method of the light emitting device, the light emitting device package and the illumination system according to the embodiment, by providing a light emitting device having a nano-class light extraction nano-pattern can significantly increase the performance of the light emitting diode.

1 is a cross-sectional view of a light emitting device according to a first embodiment.
2 to 7 are process cross-sectional views of a method of manufacturing a light emitting device according to the embodiment.
8 is a sectional view of a light emitting device according to a second embodiment;
9 is a sectional view of a light emitting device according to a third embodiment;
10 is a sectional view of a light emitting device according to a fourth embodiment;
11 is a cross-sectional view of a light emitting device package according to the embodiment.
12 is an exploded perspective view of the lighting apparatus according to the embodiment.

In the description of an embodiment, each layer (film), region, pattern, or structure is “on / over” or “under” the substrate, each layer (film), region, pad, or pattern. In the case where it is described as being formed at, "on / over" and "under" include both "directly" or "indirectly" formed. do. In addition, the reference to the top / top or bottom of each layer will be described with reference to the drawings.

In the drawings, the thickness or size of each layer is exaggerated, omitted, or schematically illustrated for convenience and clarity of description. In addition, the size of each component does not necessarily reflect the actual size.

(Example)

Recently, the light emitting diode has greatly improved the internal quantum efficiency due to the development of epitaxial growth technology, but the external light extraction efficiency is low.

When light generated in the multi quantum well (MQW), the active layer (light emitting layer) of the light emitting diode is emitted, total reflection occurs at the boundary between the light emitting diode element (GaN), external air, external encapsulant epoxy, and sapphire substrate, etc. do.

Compared to air (n _air = 1), epoxy (n _epoxy = 1.5), and sapphire (n _{sap .} = 1.77), GaN has a large refractive index of about 2.5. The critical angles that can be defined are GaN / air = 23 °, GaN / epoxy = 37 ° and GaN / sap = 45 °, respectively.

Therefore, the light incident out of the critical angle range toward the outside of the device does not proceed to the outside, but is totally reflected until absorbed inside the device, so the light extraction efficiency is very low, only a few%. This also causes a problem that leads to heat generation of the device.

In order to overcome the limitation of the nitride-based light emitting diode in the prior art has been studied to effectively reduce the total reflection through the diffuse reflection of light by inserting a pattern in the p-GaN layer or the transparent electrode layer of the device surface.

For example, it is known that the light extraction efficiency increases when a photonic crystal pattern in which patterns of a certain size are regularly arranged in a compact manner is introduced into a light emitting diode manufacturing process.

However, considering the manufacturing process, production yield, and economic efficiency of light emitting diodes such as p-type electrode formation and packaging process after patterning, the patterning process of the p-GaN layer and the transparent electrode layer is not practical to commercialize.

As an alternative to this, when the epitaxial layer is grown on a patterned sapphire substrate (PSS), the light extraction efficiency may be improved due to the same light reflection effect.

PSS was originally developed to increase the internal quantum efficiency by reducing the spreading dislocation density due to lattice mismatch between the sapphire substrate and the GaN epilayer. It can be improved, and there is an advantage that can be directly applied to the manufacturing process of the light emitting diode, and at present, domestic and overseas manufacturers of light emitting diodes have been mass-producing products using PSS.

In addition, in order to develop a high light output light emitting diode device, a light emitting diode device having a vertical structure in which p and n electrodes are positioned above and below the light emitting diode device has been studied.

In the case of the vertical light emitting diode device, since the heat dissipation characteristics are improved compared to the light emitting diode of the conventional side structure, the device is operated even at a higher injection current, thereby making it possible to manufacture a light emitting diode device having a higher light output.

On the other hand, the light emitting diode forms roughness on the surface through PEC (Photoelectro chemical) etching in order to minimize the total surface reflection in the case of the vertical light emitting diode to ensure high output through heat resistance.

However, an additional etching process is required to form the surface roughness, thereby adding a process cost. The PEC structure is a random surface roughness structure and is not optimized for improving the light extraction efficiency of the light emitting diode device.

In addition, since the structure of the conventional PEC structure is not uniform in a large area device of more than 4 inches, a patterning technique suitable for a large area light emitting diode device is required.

In addition, PSS is mainly manufactured through photolithography process and dry and wet etching process, but the specification of pattern is mostly in the order of several micro level.

On the other hand, the improvement of the light extraction efficiency of the light emitting diode by the diffuse reflection of light varies greatly depending on the size, shape, period, etc. of the pattern.

As reported to date, it is known that the light extraction enhancement is greatly increased when the photonic crystal pattern is applied in the light emitting region of the light emitting diode.

Therefore, in order to improve the efficiency of the light emitting device, it is necessary to reduce the diameter and period of the micron-class pattern of the conventionally commercially available PSS to nano-scale.

Photolithography, a patterning technology currently used for PSS fabrication, is expensive, and the manufacturing cost of the product is expensive and economical to be significantly reduced to apply sub-micron patterns. Improvement of extraction efficiency is difficult to expect.

Therefore, in order to maximize the light extraction efficiency of light emitting diodes through PSS, a patterning technique is needed to economically manufacture sub-micron-level patterns to replace expensive photolithography.

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

The light emitting device 100 according to the embodiment includes a substrate 70, a second conductive semiconductor layer 13 on the substrate 70, and an active layer 12 on the second conductive semiconductor layer 13. And, the first conductive semiconductor layer 11 and the first conductive semiconductor layer 11 on the active layer 12 may include a first light extraction nano-pattern (25). The substrate 70 may include a conductive substrate or a non-conductive substrate.

1 illustrates a vertical light emitting device, but the embodiment is not limited thereto and may be applied to a horizontal light emitting device.

The first light extraction nanopattern 25 may have a width different from an upper portion and a lower portion.

The first light extracting nanopattern 25 may have a sub-micron, that is, a size of less than 1 μm. For example, the size of the first light extraction nanopattern 25 may mean a maximum horizontal width when the first light extraction nanopattern 25 is a polygon, and may mean a maximum diameter when it is spherical. .

An embodiment may include the first light extraction nanopattern 25 and the light extraction nanopattern 25 may include a light extraction nanopattern having a size of less than 1 μm, even if there is a pattern having a size of 1 μm or more. It is not excluded.

Hereinafter, a method of manufacturing a light emitting device according to an embodiment will be described with reference to FIGS. 2 to 8. On the other hand, the following manufacturing method will be described with reference to the manufacturing method of the vertical light emitting device, the embodiment is not limited to the vertical light emitting device, it is also applicable to the horizontal light emitting device.

According to the method of manufacturing the light emitting device according to the embodiment, as shown in FIG. 2, the nanoprinting pattern 22 may be coated on the mold 20.

The mold 20 may be a polymer mold material having a predetermined pattern. The nano printing pattern 22 may be formed on the mold 20 to fill a predetermined pattern of the mold.

The nanoprinting pattern 22 may be SOG, SON, or the like, but is not limited thereto. The nanoprinting pattern 22 may be formed in a form connected to each other, but may be separated from each other by an etching process in a subsequent process.

Next, as shown in FIG. 3, the mold 20 having the nanoprinting pattern 22 is pressed onto a predetermined growth substrate 5, and then the mold 20 is removed to remove the growth substrate 5 as shown in FIG. 4. The nanoprinting pattern 22 may be printed on the. In this case, when the nanoprinting pattern 22 is connected to each other, the residual layer may be removed through a predetermined etching process.

Thereafter, the nanoprinting pattern 22 may be changed to a material such as SiO ₂ or Si ₃ N ₄ through a heat treatment process.

The growth substrate 5 may be formed of, for example, at least one of sapphire substrate (Al ₂ O ₃ ), SiC, GaAs, GaN, ZnO, Si, GaP, InP, Ge, and on the growth substrate 5. A predetermined buffer layer (not shown) may be formed in the nanostructure, and the nanoprinting pattern 22 may be formed on the buffer layer, but is not limited thereto.

In an embodiment, a pattern of heterogeneous material is formed on the surface of the light emitting diode substrate using a nanoprinting technology, thereby minimizing the patterning process step and cost of the light emitting diode substrate.

Nanoimprint technology applied in the embodiment has the advantage of high production yield because it does not require expensive exposure equipment and can transfer the pattern to a large area in an economical and simple process.

In particular, since patterning for light emitting diodes does not require precise alignment, it is appropriate to apply a nanoimprint process, which is a direct pattern transfer method, and a sub-micron level pattern can be easily formed.

Therefore, when the nanoimprint technology is applied to the PSS process as compared to the conventional photolithography process for manufacturing the PSS, the performance of the product can be further improved and the economical efficiency can be mass-produced.

After removing the sapphire substrate to remove the heterogeneous material for manufacturing the vertical light emitting diode, it is possible to manufacture a vertical light emitting diode having a pattern formed on the surface thereof. This is a method that can form a nano-scale light extraction pattern without additional patterning process.

According to the embodiment, it is possible to simply form a nano-class light extraction pattern on the surface of the vertical light emitting diode without additional patterning process, it is possible to lower the manufacturing cost of the vertical light emitting diode.

In addition, according to the embodiment, it is possible to form a nano-class light extraction pattern having a period, diameter, shape suitable for the light emitting diode device, it is possible to manufacture a device having a higher light extraction efficiency than the vertical type light emitting diode with a PEC structure .

In addition, according to the embodiment, the nano printing technology is an economical large-area patterning technology, and is easily applied to the 6-inch light emitting diode device under study.

Next, as shown in FIG. 5, the first conductive semiconductor layer 11, the active layer 12, and the second conductive semiconductor layer 13 may be formed on the growth substrate 5. 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.

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

The first conductivity-type semiconductor layer 11 may include, for example, an n-type semiconductor layer. The first conductive semiconductor layer 11 is a semiconductor material having a compositional formula of _{In x Al y Ga 1 -x- y} N (0≤x≤1, 0≤y≤1, 0≤x + y≤1) Can be formed. The first conductive semiconductor layer 11 may be selected from, for example, InAlGaN, GaN, AlGaN, AlInN, InGaN, AlN, InN, and the like, and doped with an n-type dopant such as Si, Ge, Sn, Se, Te, or the like. Can be.

In the active layer 12, electrons (or holes) injected through the first conductive semiconductor layer 11 and holes (or electrons) injected through the second conductive semiconductor layer 13 meet each other. The layer emits light due to a band gap difference between energy bands of the active layer 12. The active layer 12 may be formed of any one of a single well structure, a multiple well structure, a quantum dot structure, or a quantum line structure, but is not limited thereto.

The active layer 12 may be formed of a semiconductor material having a compositional formula of _{In x Al y Ga 1 -x- y} N (0≤x≤1, 0≤y≤1, 0≤x + y≤1). When the active layer 12 is formed of the multi-well structure, the active layer 12 may be formed by stacking a plurality of well layers and a plurality of barrier layers, for example, at intervals of an InGaN well layer / GaN barrier layer. Can be formed.

The second conductive semiconductor layer 13 may be implemented with, for example, a p-type semiconductor layer. The second conductive type semiconductor layer 13 of a semiconductor material having a compositional formula of _{In x Al y Ga 1 -x- y} N (0≤x≤1, 0≤y≤1, 0≤x + y≤1) Can be formed. The second conductive semiconductor layer 13 may be selected from, for example, InAlGaN, GaN, AlGaN, InGaN, AlInN, AlN, InN, and the like, and dopants such as Mg, Zn, Ca, Sr, and Ba may be doped. Can be.

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 conductivity-type semiconductor layer 13. Accordingly, the light emitting structure 10 may be np, pn, npn, or pnp junctions. It may have at least one of the structures. In addition, the doping concentrations of the impurities in the first conductive semiconductor layer 11 and the second conductive semiconductor layer 13 may be uniformly or non-uniformly formed. That is, the structure of the light emitting structure 10 may be formed in various ways, but is not limited thereto.

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

Next, as shown in FIG. 6, a portion of the first conductivity-type semiconductor layer 11 may be exposed by etching the light emitting structure 10. In this case, the etching may be performed by wet etching or dry etching.

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

For example, the channel layer 30 may include at least one of Si0 ₂ , Si _x O _y , Si ₃ N ₄ , Si _x N _y , SiO _x N _y , Al ₂ O ₃ , TiO ₂ , AlN, and the like. Can 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 to be in ohmic contact with the light emitting structure 10. The reflective layer 17 may be electrically connected to the second conductivity type 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 layer. The ohmic contact pattern 15 may include, for example, indium tin oxide (ITO), indium zinc oxide (IZO), aluminum zinc oxide (AZO), aluminum gallium zinc oxide (AGZO), indium zinc tin oxide (IZTO), and inaz Aluminum Zinc Oxide (IGZO), Indium Gallium Zinc Oxide (IGZO), Indium Gallium Tin Oxide (IGTO), Antimony Tin Oxide (ATO), Gallium Zinc Oxide (GZO), IZON (IZO Nitride), ZnO, IrOx, RuOx, NiO, Pt It may be formed of at least one material selected from Ag, Ti.

The reflective layer 17 may be formed of a material having a high reflectance. 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. In addition, the reflective layer 17 may be formed of indium-tin-oxide (ITO), indium-zinc-oxide (IZO), indium-zinc-tin-oxide (IZTO), and indium-aluminum-zinc- (AZO). Light-transmitting materials such as Oxide), Indium-Gallium-Zinc-Oxide (IGZO), Indium-Gallium-Tin-Oxide (IGTO), Aluminum-Zinc-Oxide (AZO), and Antimony-Tin-Oxide (ATO) It can be formed in multiple layers. For example, in the exemplary 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 be formed by alternately forming an Ag layer and a Ni layer, and may include a Ni / Ag / Ni, Ti layer, or Pt layer. In addition, the ohmic contact pattern 15 may be formed under the reflective layer 17, and at least part of the ohmic contact pattern 15 may be in ohmic contact with the light emitting structure 10 through the reflective layer 17.

Subsequently, a metal layer 50, a bonding layer 60, a substrate 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 materials. The metal layer 50 may also function as a diffusion barrier layer.

In example embodiments, 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 all of the reflective layer, the ohmic contact layer, and the metal layer, and may include one layer or two layers.

The metal layer 50 may function to prevent the material included in the bonding layer 60 from diffusing in the direction of 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 (Sn) included in the bonding layer 60 from affecting the reflective layer 17.

The bonding layer 60 may include a barrier metal or a bonding metal, and for example, at least one of Ti, Au, Sn, Ni, Cr, Ga, In, Bi, Cu, Ag, Nb, Pd, or Ta. It may include. The substrate 70 may support the light emitting structure 10 according to the embodiment and perform a heat radiation function. The bonding layer 60 may be implemented as a seed layer.

The substrate 70 may function as a support substrate, for example, a semiconductor substrate (eg, Si, Ti, Cr, Ni, Al, Pt, Au, W, Cu, Mo, Cu-W, or impurity implanted therein). , Ge, GaN, GaAs, ZnO, SiC, SiGe, etc.). In addition, the substrate 70 may be formed of an insulating material.

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

Next, as shown in FIG. 7, the growth substrate 5 is removed from the gallium nitride semiconductor layer 14. As an example, the growth substrate 5 may be removed by a laser lift off (LLO) process. The laser lift-off process LLO is a process of irradiating a lower surface of the growth substrate 5 to peel the growth substrate 5 and the gallium nitride semiconductor layer 14 from each other.

Thereafter, the first light extracting nanopattern 25 may be formed by removing the nanoprinting pattern 22 by wet etching.

In an embodiment, an isolation etching process, a pad electrode 81 forming process, a scribing process, a reflecting unit 40 forming process, and the temporary substrate 90 removing process may be performed. This process is one example, and the process order may be variously modified as necessary.

According to an embodiment, the side surface of the light emitting structure 10 may be etched by performing isolation etching, and a portion of the channel layer 30 may be exposed. The isolation etching may be performed by dry etching such as, for example, an inductively coupled plasma (ICP), but is not limited thereto.

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 conductivity 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 may be applied to the light emitting structure 10 through the pad electrode 81 and the substrate 70.

The pad electrode 81 may be implemented as an ohmic layer, an intermediate layer, and an upper layer. The ohmic layer may include a material selected from Cr, V, W, Ti, and Zn to implement ohmic contact. The intermediate layer may be implemented with a material selected from Ni, Cu, Al, and the like. The top layer may comprise Au, for example. The pad electrode 81 may include at least one of Cr, V, W, Ti, Zn, Ni, Cu, Al, Au.

In addition, a scribing process may be performed to expose side surfaces of the channel layer 30 and the substrate 70. Subsequently, the reflector 40 may be formed on the side of the channel layer 30 and the side of the substrate 70. Thereafter, the temporary substrate 90 is removed to form individual light emitting devices.

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

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

The reflector 40 may be made of a material having good reflectance. For example, the reflector 40 may include at least one of Ag, Al, and Pt. The reflector 40 may be formed to have a thickness of, for example, 50 nanometers to 5000 nanometers.

The reflector 40 prevents light emitted from the light emitting structure 10 from being incident on and absorbed by the channel layer 30, the metal layer 50, the bonding layer 60, and the substrate 70. can do. That is, the reflector 40 reflects the light incident from the outside so that the light is absorbed and lost in the channel layer 30, the metal layer 50, the bonding layer 60, and the substrate 70. It can be prevented.

As the reflector 40 is disposed, roughness may be applied to any one of a side surface of the channel layer 30, a side surface of the metal layer 50, a side surface of the bonding layer 60, and a side surface of the substrate 70. Even if formed, the sides of the light emitting device according to the embodiment can all be implemented smoothly. That is, since the surface of the reflector 40 may be smoothly formed, the side of the channel layer 30, the side of the metal layer 50, the side of the bonding layer 60, the substrate ( Even when roughness or burr is formed on any one of the side surfaces of 70, all of the side surfaces of the light emitting device according to the embodiment may be smoothly implemented.

According to the embodiment, it is possible to simply form a nano-class light extraction pattern on the surface of the vertical light emitting diode without additional patterning process, it is possible to lower the manufacturing cost of the vertical light emitting diode.

In addition, according to the embodiment, it is possible to form a pattern having a period, diameter, shape suitable for the light emitting diode device, it is possible to manufacture a device having a higher light extraction efficiency than a vertical light emitting diode with a conventional PEC structure.

In addition, according to the embodiment, the nano printing technology is an economical large-area patterning technology, and is easily applied to the 6-inch light emitting diode device under study.

8 is a sectional view of a light emitting element 102 according to the second embodiment.

The second embodiment can employ the technical features of the first embodiment.

In the second embodiment, the second light extracting nanopattern 27 may include a hemispherical cross section recessed downward. This may be possible by controlling the nanoprinting pattern shape to have a hemispherical cross section.

According to the embodiment, since the second light extraction nanopattern 27 has a concave hemispherical cross section, the external light extraction efficiency can be significantly increased.

The pattern of the conventional light extraction structure was difficult to etch to have a concave hemispherical cross section, and there was a problem that the damage was applied to the epi layer during etching, thereby lowering reliability, and it was difficult to precisely control the light extraction pattern.

According to the embodiment, by precisely controlling the nanoprinting pattern, the second light extracting nanopattern 27 may have a hemispherical cross section recessed downward.

9 is a sectional view of a light emitting element 103 according to the third embodiment.

The third embodiment can employ the technical features of the first embodiment.

The third embodiment may include the first light scattering nanopattern 23 between the light extraction nanopatterns 25 to maximize the external light extraction efficiency.

The first light scattering nanopattern 23 may have a width differently between an upper portion and a lower portion.

For example, the first light scattering nanopattern 23 may be formed by forming the nanoprinting pattern material as a light scattering material and not removing it.

For example, the first light scattering nanopattern 23 may include a material such as a light transmissive oxide, a nitride, a polymer, but is not limited thereto. For example, the first light scattering nanopattern 23 may include at least one of ZnO, a glass paste composition, silver (Ag), aluminum (Al), silica, and aluminum hydroxide (Al (OH) ₃ ). It is not limited.

10 is a cross-sectional view of the light emitting device 104 according to the fourth embodiment.

The fourth embodiment can employ the technical features of the first and third embodiments.

In the fourth embodiment, the second light scattering pattern 24 may have a semispherical cross section recessed downward. Through this, effective light extraction may be possible.

According to the light emitting device, the manufacturing method of the light emitting device, the light emitting device package and the illumination system according to the embodiment, by providing a light emitting device having a nano-class light extraction nano-pattern can significantly increase the performance of the light emitting diode.

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

Referring to FIG. 11, the light emitting device package according to the embodiment includes a body 120, a first lead electrode 131 and a second lead electrode 132 disposed on the body 120, and the body 120. The light emitting device 100 according to the embodiment provided to and electrically connected to the first lead electrode 131 and the second lead electrode 132, and a molding member 140 surrounding the light emitting device 100. It may include.

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

The first lead electrode 131 and the second lead electrode 132 are electrically separated from each other, and provide power to the light emitting device 100. In addition, the first lead electrode 131 and the second lead electrode 132 may increase light efficiency by reflecting light generated from the light emitting device 100, and heat generated from the light emitting device 100. It may also play a role in discharging it to the outside.

The light emitting device 100 may be disposed on the body 120 or 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 any one of a wire method, a flip chip method, or a 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 the light emitted from the light emitting device 100.

A plurality of light emitting devices or light emitting device packages according to the embodiment may be arranged on a substrate, and an optical member such as a lens, a light guide plate, a prism sheet, a diffusion sheet, and the like may be disposed on the light path of the light emitting device package. The light emitting device package, the substrate, and the optical member may function as a light unit. The light unit may be implemented in a top view or a side view type, and may be provided to a display device such as a portable terminal and a notebook computer, or may be variously applied to an illumination device and a pointing device. Yet another embodiment may be implemented 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 street lamp, a sign, a headlamp.

12 is an exploded perspective view of the lighting apparatus according to the embodiment.

Referring to FIG. 12, the lighting apparatus according to the embodiment may include a cover 2100, a light source module 2200, a radiator 2400, a power supply 2600, an inner case 2700, and a socket 2800. Can be. In addition, the lighting apparatus according to the embodiment may further include any one or more 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 bulb or hemisphere shape, and may be provided in a hollow shape and a part of which 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 the light provided from the light source module 2200. The cover 2100 may be a kind of optical member. The cover 2100 may be combined with the radiator 2400. The cover 2100 may have a coupling part coupled to the heat sink 2400.

An inner surface of the cover 2100 may be coated with a milky paint. The milky paint may include a diffuser that diffuses light. The surface roughness of the inner surface of the cover 2100 may be greater than the surface roughness of the outer surface of the cover 2100. This is for the light from the light source module 2200 to be sufficiently scattered and diffused and emitted 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 or opaque so that the light source module 2200 is visible from the outside. The cover 2100 may be formed through blow molding.

The light source module 2200 may be disposed on one surface of the heat sink 2400. Therefore, heat from the light source module 2200 is conducted to the heat sink 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 an upper surface of the heat dissipator 2400 and has a plurality of light source parts 2210 and guide grooves 2310 into which the connector 2250 is inserted. The guide groove 2310 corresponds to the board and the connector 2250 of the light source unit 2210.

The surface of the member 2300 may be coated or coated with a light reflective material. For example, the surface of the member 2300 may be coated or coated with a white paint. The member 2300 is reflected on the inner surface of the cover 2100 to reflect the light returned to the light source module 2200 side again toward the cover 2100. Therefore, it is possible to improve the light efficiency of the lighting apparatus according to the embodiment.

The member 2300 may be made of, for example, an insulating material. The connection plate 2230 of the light source module 2200 may include an electrically conductive material. Therefore, electrical contact may be made between the radiator 2400 and the connection plate 2230. The member 2300 may be made of an insulating material to block an electrical short between the connection plate 2230 and the radiator 2400. The radiator 2400 receives heat from the light source module 2200 and heat from the power supply unit 2600 to radiate heat.

The holder 2500 may block the accommodating groove 2719 of the insulating portion 2710 of the inner case 2700. Therefore, the power supply unit 2600 accommodated in the insulating unit 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 to provide the light source module 2200. The power supply unit 2600 is accommodated in the accommodating groove 2725 of the inner case 2700, and is sealed in the inner case 2700 by the holder 2500.

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

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

The extension part 2670 has a shape protruding outward from the other side of the base 2650. The extension part 2670 is inserted into the connection part 2750 of the inner case 2700 and receives an electrical signal from the outside. For example, the extension part 2670 may be provided equal to or smaller than the width of the connection part 2750 of the inner case 2700. Each end of the "+ wire" and the "-wire" may be electrically connected to the extension 2670, and the other end of the "+ wire" and the "-wire" may be electrically connected to the socket 2800. .

The inner case 2700 may include a molding part together with the power supply part 2600 therein. The molding part is a part where the molding liquid is hardened, so that the power supply part 2600 can be fixed inside the inner case 2700.

According to the light emitting device, the manufacturing method of the light emitting device, the light emitting device package and the illumination system according to the embodiment, by providing a light emitting device having a nano-class light extraction nano-pattern can significantly increase the performance of the light emitting diode.

Features, structures, effects, etc. described in the above embodiments are included in at least one embodiment, but are not necessarily limited to one embodiment. Furthermore, the features, structures, effects, and the like illustrated in the embodiments may be combined or modified with respect to other embodiments by those skilled in the art to which the embodiments belong. Therefore, it should be interpreted that the contents related to such combinations and modifications are included in the scope of the embodiments.

Although the embodiments have been described above, the embodiments are merely examples and are not intended to limit the embodiments, and those skilled in the art to which the embodiments pertain may have several examples that are not exemplified above without departing from the essential characteristics of the embodiments. It will be appreciated that modifications and applications of the branches are possible. For example, each component specifically shown in the embodiment can be modified. And differences relating to these modifications and applications will have to be construed as being included in the scope of the embodiments set out in the appended claims.

The substrate 70, the second conductivity-type semiconductor layer 13,
Active layer 12, first conductivity-type semiconductor layer 11,
Light extraction nanopatterns (25, 27), light scattering nanopatterns (23, 24)

Claims (11)

Board;
A second conductivity type semiconductor layer disposed on the substrate; An active layer disposed on the second conductivity type semiconductor layer; And a first conductivity type semiconductor layer on the active layer;
A pad electrode disposed on the first conductive semiconductor layer and electrically connected to the first conductive semiconductor layer;
Light extraction nanopatterns having different widths from upper and lower portions on the first conductivity type semiconductor layer; And
And a light scattering nanopattern between the light extraction nanopatterns.
The light scattering nanopattern includes a material different from the light emitting structure,
An upper surface of the first conductivity type semiconductor layer may include a first region in which the light extraction nanopattern and the light scattering nanopattern are formed; And a second region around the first region,
The horizontal width of the first region is greater than the horizontal width of the active layer and the second conductive semiconductor layer.
The pad electrode is disposed on the second region. According to claim 1,
The light extraction nanopattern and the light scattering nanopattern
Light emitting device comprising a hemispherical cross section. According to claim 1,
The light scattering nanopattern is
Light emitting device having a different width at the top and the bottom. According to claim 1,
The light scattering nanopattern includes at least one of an oxide, a nitride and a polymer. Preparing a growth substrate;
Forming a nano printing pattern on the growth substrate;
Forming a light emitting structure including a first conductivity type semiconductor layer, an active layer, and a second conductivity type semiconductor layer on the growth substrate on which the nanoprinting pattern is formed;
Removing the growth substrate from the light emitting structure;
Removing the nanoprinting pattern to form a light extraction nanopattern and a light scattering nanopattern on the light emitting structure; And
Forming a pad electrode on the light emitting structure;
Forming a nano printing pattern on the growth substrate,
Filling the nanoprinting pattern material into a pattern of a mold including a predetermined pattern;
Pressing the mold on which the nanoprinting pattern material is filled into the pattern on the growth substrate; And
Removing the mold;
The light scattering nanopattern includes a material different from the light emitting structure,
An upper surface of the first conductivity type semiconductor layer may include a first region in which the light extraction nanopattern and the light scattering nanopattern are formed; And a second region around the first region,
The horizontal width of the first region is greater than the horizontal width of the active layer and the second conductive semiconductor layer.
And the pad electrode is disposed on the second region. The method of claim 5,
The light extraction nano pattern is
A method of manufacturing a light emitting device having a width different from an upper part and a lower part. The method of claim 5,
The light extraction nano pattern is
Method of manufacturing a light emitting device comprising a hemispherical cross section. In claim 5,
Between forming the light emitting structure and removing the growth substrate from the light emitting structure,
Etching a portion of the light emitting structure to open a portion of the first conductivity type semiconductor layer;
Forming a channel layer on the light emitting structure;
Forming an ohmic layer including an ohmic contact pattern and a reflective layer on the light emitting structure and the channel layer;
Forming a metal layer on the channel layer and the ohmic layer;
Forming a bonding layer on the metal layer; And
Forming a substrate on the bonding layer manufacturing method of a light emitting device. The method of claim 4, wherein
The light scattering nanopattern includes at least one of ZnO, a glass paste composition, silver (Ag), aluminum (Al), silica, and aluminum hydroxide (Al (OH) ₃ ). According to claim 1,
A bonding layer disposed between the substrate and the light emitting structure;
A metal layer disposed between the bonding layer and the light emitting structure;
An ohmic layer disposed between the metal layer and the light emitting structure;
A channel layer disposed between the ohmic layer and the light emitting structure; And
A reflector disposed on a side of the substrate, a side of the bonding layer, a side of the metal layer, a side of the channel layer, and a portion of an upper surface of the channel layer,
The reflector is spaced apart from the light emitting structure in a horizontal direction, the light emitting device having a thickness of 50nm to 5000nm. delete

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