KR20130007172A

KR20130007172A - Light emitting device, light emitting device package, and light unit

Info

Publication number: KR20130007172A
Application number: KR1020110064100A
Authority: KR
Inventors: 김태진
Original assignee: 엘지이노텍 주식회사
Priority date: 2011-06-29
Filing date: 2011-06-29
Publication date: 2013-01-18

Abstract

PURPOSE: A light emitting device, a light emitting package, and a light unit are provided to improve the luminous efficiency of the light emitting device by reducing current concentration in the shortest distance between an electrode and a reflection electrode through a current blocking layer between a light emitting structure and an ohmic contact layer. CONSTITUTION: A light emitting structure(10) includes a first conductive semiconductor layer(11), an active layer(12), and a second conductive semiconductor layer(13). An electrode(20) is formed on the light emitting structure. A reflection electrode(50) is formed on the lower side of the light emitting structure. A resin layer(97) is formed on the light emitting structure. The resin layer includes a transparent scattering particle(95). A current blocking layer(30) is formed between the light emitting structure and an ohmic contact layer(40).

Description

LIGHT EMITTING DEVICE, LIGHT EMITTING DEVICE PACKAGE, AND LIGHT UNIT}

Embodiments relate to a light emitting device, a light emitting device package, and a light unit.

Light emitting diodes (LEDs) are widely used as one of light emitting devices. Light-emitting diodes use the properties of compound semiconductors to convert electrical signals into light, such as infrared or visible light.

Recently, as the light efficiency of the light emitting device is increased, it is used in various fields including a display device and a lighting device.

The embodiment provides a light emitting device, a light emitting device package, and a light unit having a new structure.

The embodiment provides a light emitting device, a light emitting device package, and a light unit capable of improving light extraction efficiency and widening a directing angle at which light is extracted.

The light emitting device according to the embodiment may include a light emitting structure including a first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer; An electrode disposed on the light emitting structure; A reflective electrode disposed under the light emitting structure; A resin layer disposed on the light emitting structure and including transparent scattering particles; .

The light emitting device according to the embodiment may include a light emitting structure including a first conductive semiconductor layer, an active layer under the first conductive semiconductor layer, and a second conductive semiconductor layer under the active layer; A first electrode electrically connected to the first conductive semiconductor layer; A second electrode electrically connected to the second conductive semiconductor layer; A resin layer disposed on the light emitting structure and including transparent scattering particles; .

The light emitting device package according to the embodiment includes a body; A light emitting element disposed on the body; A first lead electrode and a second lead electrode electrically connected to the light emitting element; The light emitting device includes: a light emitting structure including a first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer; An electrode disposed on the light emitting structure; A reflective electrode disposed under the light emitting structure; A resin layer disposed on the light emitting structure and including transparent scattering particles; .

The light emitting device package according to the embodiment includes a body; A light emitting element disposed on the body; A first lead electrode and a second lead electrode electrically connected to the light emitting element; The light emitting device includes: a light emitting structure including a first conductive semiconductor layer, an active layer under the first conductive semiconductor layer, and a second conductive semiconductor layer under the active layer; A first electrode electrically connected to the first conductive semiconductor layer; A second electrode electrically connected to the second conductive semiconductor layer; A resin layer disposed on the light emitting structure and including transparent scattering particles; .

According to an embodiment, a light unit includes a substrate; A light emitting element disposed on the substrate; An optical member through which light provided from the light emitting device passes; The light emitting device includes: a light emitting structure including a first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer; An electrode disposed on the light emitting structure; A reflective electrode disposed under the light emitting structure; A resin layer disposed on the light emitting structure and including transparent scattering particles; .

According to an embodiment, a light unit includes a substrate; A light emitting element disposed on the substrate; An optical member through which light provided from the light emitting device passes; The light emitting device includes: a light emitting structure including a first conductive semiconductor layer, an active layer under the first conductive semiconductor layer, and a second conductive semiconductor layer under the active layer; A first electrode electrically connected to the first conductive semiconductor layer; A second electrode electrically connected to the second conductive semiconductor layer; A resin layer disposed on the light emitting structure and including transparent scattering particles; .

The embodiment can provide a light emitting device, a light emitting device package, and a light unit having a new structure.

The embodiment can provide a light emitting device, a light emitting device package, and a light unit that can improve light extraction efficiency and widen a directing angle at which light is extracted.

1 is a view showing a light emitting device according to an embodiment.
2 and 3 illustrate a modified example of the light emitting structure of FIG. 1.
4 to 11 are views for explaining a method of manufacturing a light emitting device according to the embodiment.
12 is a view showing a light emitting device package to which the light emitting device according to the embodiment is applied.
13 is a diagram illustrating an example of a display device to which a light emitting device is applied, according to an exemplary embodiment.
14 is a diagram illustrating another example of a display device to which a light emitting device is applied, according to an exemplary embodiment.
15 is a diagram illustrating an example of a lighting device to which a light emitting device is applied, according to an embodiment.

In the description of the embodiments, it is to be understood that each layer (film), region, pattern or structure may be referred to as being "on" or "under" a substrate, each layer It is to be understood that the terms " on "and " under" include both " directly "or" indirectly " do. In addition, the criteria for the top / bottom or bottom / bottom of each layer are described with reference to the drawings.

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

Hereinafter, a light emitting device, a light emitting device package, a light unit, and a light emitting device manufacturing method according to embodiments will be described in detail with reference to the accompanying drawings.

1 is a view showing a light emitting device according to an embodiment.

As shown in FIG. 1, the light emitting device 100 according to the embodiment includes a light emitting structure 10, an electrode 20, a current blocking layer 30, an ohmic contact layer 40, a reflective electrode 50, The resin layer 97 containing the transparent scattering particles 95 is included.

The light emitting structure 10 may include a first conductive semiconductor layer 11, an active layer 12, and a second conductive semiconductor layer 13. For example, the first conductivity type semiconductor layer 11 is formed of an n-type semiconductor layer doped with an n-type dopant as a first conductivity type dopant, and the second conductivity type semiconductor layer 13 is formed of an n- Type semiconductor layer to which a p-type dopant is added. In addition, 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 conductive semiconductor layer 11 may include, for example, an n-type semiconductor layer. The first conductive semiconductor layer 11 is a semiconductor material having a compositional formula of _{In x Al y Ga 1 -x- y} N (0≤x≤1, 0≤y≤1, 0≤x + y≤1) Can be implemented. The first conductive semiconductor layer 11 may be selected from among GaN, AlN, AlGaN, InGaN, InN, InAlGaN, AlInN, AlGaAs, GaP, GaAs, GaAsP, AlGaInP, An n-type dopant such as Se or Te can be doped.

The active layer 12 is formed in such a manner that electrons (or holes) injected through the first conductive type semiconductor layer 11 and holes (or electrons) injected through the second conductive type semiconductor layer 13 meet with each other, And is a layer that emits light due to a band gap difference of an energy band according to a material of the active layer 12. [ The active layer 12 may be formed of any one of a single quantum well structure, a multi quantum well structure (MQW), a quantum dot structure, or a quantum line structure, but is not limited thereto.

The active layer 12 may be embodied as 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 + have. When the active layer 12 is implemented as the multi quantum well structure, the active layer 12 may be implemented by stacking a plurality of well layers and a plurality of barrier layers, for example, an InGaN well layer / GaN barrier layer. It can be implemented in the cycle of.

The second conductive semiconductor layer 13 may be formed of, 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 implemented. The second conductive semiconductor layer 13 may be selected from GaN, AlN, AlGaN, InGaN, InN, InAlGaN, AlInN, AlGaAs, GaP, GaAs, GaAsP, AlGaInP, A p-type dopant such as Sr, Ba or the like may be doped.

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 below the second conductive semiconductor layer 13. Accordingly, the light emitting structure 10 may have at least one of np, pn, npn, and pnp junction 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 variously formed, but the present invention is not limited thereto.

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

The ohmic contact layer 40 and the reflective electrode 50 may be disposed under the light emitting structure 10. The electrode 20 may be disposed on the light emitting structure 10. The electrode 20 and the reflective electrode 50 may provide power to the light emitting structure 10. The ohmic contact layer 40 may be formed to be in ohmic contact with the light emitting structure 10. In addition, the reflective electrode 50 may perform a function of increasing the amount of light extracted to the outside by reflecting light incident from the light emitting structure 10.

The ohmic contact layer 40 may be formed of, for example, a transparent conductive oxide layer. The ohmic contact layer 40 includes, 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, RuOx / ITO, Ni / IrOx / Au, Ni / IrOx / Au / ITO, Ag, Ni, Cr, Ti, Al, Rh, Pd, Ir, Sn, In, Ru, Mg, Zn, Pt, Au, Hf It may be formed of at least one material.

The reflective electrode 50 may be formed of a metal material having a high reflectance. For example, the reflective electrode 50 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 electrode 50 may be formed of indium-tin-oxide (ITO), indium-zinc-oxide (IZO), indium-zinc-tin-oxide (IZTO), and indium-aluminum-zinc (AZO). Transmissive conductive materials such as -Oxide, Indium-Gallium-Zinc-Oxide, IGTO, Indium-Gallium-Tin-Oxide, AZO, Aluminum-Zinc-Oxide, and ATO It can be formed in a multi-layer. For example, in the exemplary embodiment, the reflective electrode 50 may include at least one of Ag, Al, Ag-Pd-Cu alloy, or Ag-Cu alloy.

The current blocking layer (CBL) 30 may be disposed between the light emitting structure 10 and the ohmic contact layer 40. The current blocking layer 30 may be formed in a region in which at least a portion of the current blocking layer overlaps with the electrode 20 in a vertical direction. By reducing the phenomenon of concentration can improve the luminous efficiency of the light emitting device according to the embodiment.

The current blocking layer 30 may have electrical insulation or may be formed using a material for forming a schottky contact with the light emitting structure 10. The current blocking layer 30 may be formed of an oxide, nitride, or metal. The current blocking layer 30 may include, for example, at least one of SiO ₂ , SiO _x , SiO _x N _y , Si ₃ N ₄ , Al ₂ O ₃ _, TiO _x , Ti, Al, Cr. .

The current blocking layer 30 may be disposed in a first area under the light emitting structure 10, and the ohmic contact layer 40 may include a second area under the light emitting structure 10 and the current blocking layer ( 30) can be placed below. The ohmic contact layer 40 may be disposed between the light emitting structure 10 and the reflective electrode 50. In addition, the ohmic contact layer 40 may be disposed between the current blocking layer 30 and the reflective electrode 50.

An isolation layer 80 may be further disposed between the light emitting structure 10 and the ohmic contact layer 40. The isolation layer 80 may be disposed on the lower circumference of the light emitting structure 10 and on the ohmic contact layer 40. The isolation layer 80 may be formed of, for example, a material having electrical insulation or a material having low electrical conductivity compared to the light emitting structure 10. The isolation layer 80 may be formed of, for example, oxide or nitride. For example, the isolation layer 80 is made 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 , ITO, AZO, ZnO, and the like. At least one selected from the group may be formed. The isolation layer 80 may be formed of the same material as the current blocking layer 30 or may be formed of different materials. The isolation layer 80 may also be referred to as a channel layer.

The bonding layer 60 and the conductive support member 70 may be disposed below the reflective electrode 50. The bonding layer 60 may include a barrier metal or a bonding metal, and may include, for example, at least one of Ti, Au, Sn, Ni, Cr, Ga, In, Bi, Cu, Ag, or Ta. . The conductive support member 70 supports the light emitting device according to the embodiment, and may be electrically connected to an external electrode to provide power to the light emitting structure 10. The conductive support member 70 may be, for example, a carrier wafer (eg, Si, Ge, Ti, Cr, Ni, Al, Pt, Au, W, Cu, Mo, Cu-W, or a semiconductor substrate into which impurities are implanted). GaN, GaAs, ZnO, SiC, SiGe, etc.) may be formed of at least one.

The resin layer 97 may be disposed on the light emitting structure 10. The resin layer 97 may include transparent scattering particles 95. The resin layer 97 may include epoxy or silicon. The refractive index of the transparent scattering particles 95 may be implemented to have a larger value than that of the resin layer 97. The refractive index of the transparent scattering particles 95 may be implemented to have a smaller value than that of the light emitting structure 10. The transparent scattering particles 95 may have a smaller value than the refractive index of the first conductivity type semiconductor layer 11 and a larger value than the resin layer 97. For example, the light emitting structure 10 may be formed of a GaN layer having a refractive index of 2.45, the transparent scattering particles 95 may have a material having a refractive index of 1.8, and the resin layer 97 may be formed of silicon having a refractive index of 1.54. Can be. The light emitting structure 10, the transparent scattering particles 95, and the resin layer 97 are selected to have such a difference in refractive index, thereby increasing the light extraction effect extracted from the light emitting structure 10 to the outside. do.

The transparent scattering particles 95 may be disposed in the form of a mono layer on the resin layer 97. The transparent scattering particles 95 may be mixed with the resin layer 97 and provided on the light emitting structure 10. The transparent scattering particles 85 may be embodied as small particles such that the absorption coefficient of the material is ignored. The transparent scattering particles 95 may be implemented to have a size of, for example, 100 nanometers to 20 micrometers. The transparent scattering particle 95 according to the embodiment scatters light incident in the direction of the light emitting structure 10. Accordingly, the light provided from the light emitting structure 10 is scattered and extracted to the outside to widen the directivity angle. That is, the light distribution pattern of the light emitting device can be widened. Accordingly, when applied to a light emitting device package including a phosphor, it is possible to widen the directivity angle and improve the white light conversion efficiency.

The transparent scattering particles 95 may be implemented as a silicate-based material as an example. The transparent scattering particles 95 are, for example, Ba ₃ MgSi ₂ O ₈ , (Ba, Sr, Ca) ₂ SiO ₄ , Ba ₂ MgSi ₂ O ₇ , Ba ₂ ZnSi ₂ O ₇ , (Ba, Mg) SiO ₄ , Ba ₂ MgSi ₂ O ₇ And the like.

The passivation layer 90 may be further disposed on the light emitting structure 10. The protective layer 90 may be formed of oxide or nitride. The protective layer 90 may be, for example, SiO ₂ , SiO _x , SiO _x N _y , Si ₃ N ₄ , Al ₂ O ₃ It may be formed of a material having a light transmitting and insulating properties. The protective layer 90 may be provided on the side surface of the light emitting structure 10. In addition, the protective layer 90 may be provided not only on the side surface of the light emitting structure 10 but also on the upper side.

The upper surface of the light emitting structure 10 may be provided in a flat or curved surface. The upper surface of the light emitting structure 10 may include a curved surface having a continuous gradient change. As such, since the upper surface of the light emitting structure 10 is provided as a curved surface having a curvature rather than a flat surface, light extraction efficiency may be improved. This is because the light propagating through the light emitting structure 10 is changed to the incident angle incident on the upper surface of the light emitting structure 10 to the outside compared to the case where the upper surface of the light emitting structure 10 is provided in a plane The amount of light that can be extracted is increased. In addition, the amount of light extracted to the outside is increased as well as the light extraction angle becomes wider. That is, as the upper surface of the light emitting structure 10 is formed as a curved surface, the width of the directivity angle from which light is extracted can be widened.

The upper surface of the light emitting structure 10 may include a curve in which the top of the cross section in the first direction has a continuous slope change, and a curve in which the top of the cross section in the second direction has a continuous slope change. Here, the second direction may be a direction perpendicular to the first direction. In addition, the second direction may be a direction having an arbitrary angle that is not perpendicular to the first direction.

As shown in FIG. 2, the light emitting device according to the embodiment may include a curve in which an upper portion of the cross section of the light emitting structure 10 has a continuous slope change. In addition, an unevenness 11a may be provided on an upper surface of the first conductivity-type semiconductor layer 11 of the light emitting structure 10. As the unevenness 11a is provided on the upper surface of the first conductivity type semiconductor layer 11, the amount of light extracted to the outside through the first conductivity type semiconductor layer 11 may be further increased. . In addition, the amount of light extracted to the outside is increased as well as the light extraction angle becomes wider. That is, as the upper cross section of the first conductivity-type semiconductor layer 10 is formed in a curve, the width of the direction angle at which light is extracted can be widened.

The unevenness 11a may be provided in a size of 0.8 to 1.2 micrometers in height. In addition, the period of the unevenness (11a) may be provided in the size of 0.8 to 1.2 micrometers. For example, an upper surface of the first conductivity type semiconductor layer 11 may be provided in a wavy curve, and the fine unevenness 11a may be further provided on the wavy upper surface.

In addition, the upper surface of the light emitting structure 10 may include a curve in which the top of the cross section in the first direction has a continuous slope change, and may include a straight line in which the top of the cross section in the second direction has different slopes. Here, the second direction may be a direction perpendicular to the first direction. In addition, the second direction may be a direction having an arbitrary angle that is not perpendicular to the first direction.

As shown in FIG. 3, the light emitting device according to the embodiment may include a straight line having different slopes at the upper end of the cross-section of the light emitting structure 10. In addition, an unevenness 11a may be provided on an upper surface of the first conductivity-type semiconductor layer 11 of the light emitting structure 10. As the unevenness 11a is provided on the upper surface of the first conductivity type semiconductor layer 11, the amount of light extracted to the outside through the first conductivity type semiconductor layer 11 may be further increased. . In addition, the amount of light extracted to the outside is increased as well as the light extraction angle becomes wider. That is, as the upper end surface of the first conductivity-type semiconductor layer 10 is formed as a straight line having an inclination, the width of the directivity angle from which light is extracted can be widened.

The unevenness 11a may be provided in a size of 0.8 to 1.2 micrometers in height. In addition, the period of the unevenness (11a) may be provided in the size of 0.8 to 1.2 micrometers. For example, the upper surface of the first conductivity type semiconductor layer 11 may be provided in a straight line having different inclinations, and the fine unevenness 11a may be further provided on the linear upper surface.

In addition, in the light emitting device according to the embodiment, the upper surface of the light emitting structure 10 may include a repeated curved surface of a predetermined shape. That is, the upper surface of the light emitting structure 10 may be implemented by repeating the wavy shape. In addition, the upper surface of the light emitting structure 10 may be provided by repeated various shapes such as spherical lens shape, concave lens shape, convex lens shape, lenticular lens shape.

For example, when the curved surface having a concave spherical surface is formed on the upper surface of the light emitting structure 10, a curved surface having a height of about 1 to 2 micrometers and a width of 10 to 50 micrometers is formed, and Fine irregularities can be formed on the curved surface.

In the above description, the electrode 20 is disposed above the light emitting structure 10 and the reflective electrode 50 is disposed below the light emitting structure 10. However, the light emitting device according to the present embodiment includes a first electrode electrically connected to the first conductive semiconductor layer 11 forming the light emitting structure 10 and a second conductive semiconductor layer forming the light emitting structure 10 ( The position and shape of the second electrode electrically connected to 12 may be variously modified. In addition, the light emitting device according to the present embodiment may be applied to a light emitting device having a horizontal structure in which the first electrode and the second electrode are exposed in the same direction.

Next, a method of manufacturing the light emitting device according to the embodiment will be described with reference to FIGS. 4 to 11.

According to the light emitting device manufacturing method according to the embodiment, as shown in Figure 4, the first conductive semiconductor layer 11, the active layer 12, the second conductive semiconductor layer ( 13). The first conductive semiconductor layer 11, the active layer 12, and the second conductive semiconductor layer 13 may be defined as a light emitting structure 10.

The 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, but is not limited thereto. A buffer layer may be further formed between the first conductivity type semiconductor layer 11 and the growth substrate 5.

For example, the first conductivity type semiconductor layer 11 is formed of an n-type semiconductor layer doped with an n-type dopant as a first conductivity type dopant, and the second conductivity type semiconductor layer 13 is formed of an n- Type semiconductor layer to which a p-type dopant is added. In addition, 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 conductive semiconductor layer 11 may include, for example, an n-type semiconductor layer. The first conductive semiconductor layer 11 is a semiconductor material having a composition formula of In _x Al _y Ga ₁ _-x- _y N (0? X? 1, 0? _Y? 1, 0? _X + . The first conductive semiconductor layer 11 may be selected from, for example, InAlGaN, GaN, AlGaN, AlInN, InGaN, AlN, InN, or the like, and may be doped with an n-type dopant such as Si, Ge, Sn, or the like.

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 quantum well structure, the active layer 12 may be formed by stacking a plurality of well layers and a plurality of barrier layers, for example, an InGaN well layer / GaN barrier layer. It may be formed in a cycle.

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

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

Subsequently, as shown in FIG. 5, a current blocking layer 30 is formed on the second conductive semiconductor layer 13, and an isolation layer 80 is formed on the second conductive semiconductor layer 13. . The current blocking layer 30 and the isolation layer 80 may be selectively formed. The current blocking layer 30 and the isolation layer 80 may be formed at the same time, or may be formed sequentially.

The current blocking layer 30 may have electrical insulation or may be formed using a material for forming a schottky contact with the light emitting structure 10. The current blocking layer 30 may be formed of an oxide, nitride, or metal. The current blocking layer 30 may include, for example, at least one of SiO ₂ , SiO _x , SiO _x N _y , Si ₃ N ₄ , Al ₂ O ₃ _, TiO _x , Ti, Al, Cr. 0. The isolation layer 80 may be formed of, for example, a material having electrical insulation or a material having low electrical conductivity compared to the light emitting structure 10. The isolation layer 80 may be formed of, for example, oxide or nitride. For example, the isolation layer 80 is made 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 , ITO, AZO, ZnO, and the like. At least one selected from the group may be formed. The isolation layer 80 may be formed of the same material as the current blocking layer 30 or may be formed of different materials. The isolation layer 80 may also be referred to as a channel layer.

As shown in FIG. 6, an ohmic contact layer 40 is formed on the current blocking layer 30 and the isolation layer 80.

The ohmic contact layer 40 may be formed to be in ohmic contact with the light emitting structure 10. The ohmic contact layer 40 may be formed of, for example, a transparent conductive oxide layer. The ohmic contact layer 40 includes, 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 indium Aluminum Zinc Oxide), Indium Gallium Zinc Oxide It may be formed of at least one material.

Subsequently, as shown in FIG. 7, the reflective electrode 50, the bonding layer 60, and the conductive support member 70 are formed on the ohmic contact layer 40.

The bonding layer 60 may include a barrier metal or a bonding metal, and may include, for example, at least one of Ti, Au, Sn, Ni, Cr, Ga, In, Bi, Cu, Ag, or Ta. . The conductive support member 70 supports the light emitting device according to the embodiment, and may be electrically connected to an external electrode to provide power to the light emitting structure 10. The conductive support member 70 may be, for example, a carrier wafer (eg, Si, Ge, Ti, Cr, Ni, Al, Pt, Au, W, Cu, Mo, Cu-W, or a semiconductor substrate into which impurities are implanted). GaN, GaAs, ZnO, SiC, SiGe, etc.) may be formed of at least one.

Next, the growth substrate 5 is removed from the light emitting structure 10. As one 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 peeling the growth substrate 5 and the light emitting structure 10 from each other by irradiating a laser onto the lower surface of the growth substrate 5.

Subsequently, as shown in FIG. 8, an etching pattern 93 is formed on the first conductivity-type semiconductor layer 11 of the light emitting structure 10.

The etching pattern 93 may be formed through, for example, a photolithography process. The etching pattern 93 is a curved surface having a fine height difference depending on the position by applying a gray scale phase mask (Mask scale) technique to finely control the exposure intensity according to the position in performing the photolithography process Can be implemented.

The upper surface of the etching pattern 93 may include a curved surface having a continuous gradient change. The upper surface of the etching pattern 93 may include a curve in which the top of the cross section in the first direction has a continuous slope change, and a curve in which the top of the cross section in the second direction has a continuous slope change. In addition, the upper surface of the etching pattern 93 may include a curve in which the top of the cross section in the first direction has a continuous slope change, and may include a straight line in which the top of the cross section in the second direction has different slopes. The second direction may be a direction perpendicular to the first direction. In addition, the second direction may be a direction having an arbitrary angle that is not perpendicular to the first direction.

The upper surface of the etching pattern 93 according to the embodiment may include a repeated curved surface of a predetermined shape. For example, the upper surface of the etching pattern 93 may be implemented by repeating a wavy shape. In addition, the upper surface of the etching pattern 93 may be provided by repeating various shapes such as spherical lens shape, concave lens shape, convex lens shape, lenticular lens shape.

For example, when the curved surface having a concave spherical surface is formed on the upper surface of the etching pattern 93, a curved surface having a height of about 1 to 2 micrometers and a width of 10 to 50 micrometers may be formed.

Next, as shown in FIG. 9, an etching process is performed on the first conductive semiconductor layer 11 of the light emitting structure 10 to continuously connect the upper surface of the first conductive semiconductor layer 11. It is formed into a curved surface having a change in inclination.

The etching process may be performed by, for example, a dry etching process. Through the etching process, the shape of the etching pattern 93 may be implemented on the upper surface of the first conductive semiconductor layer 11.

That is, the upper surface of the first conductive semiconductor layer 11 may be implemented as a curved surface having a continuous gradient change corresponding to the shape of the upper surface of the etching pattern 93. The upper surface of the first conductivity-type semiconductor layer 11 may include a curve in which the top of the cross section in the first direction has a continuous slope change, and a curve in which the top of the cross section in the second direction has a continuous slope change. have. In addition, the upper surface of the first conductivity-type semiconductor layer 11 may include a curve in which the top of the cross section in the first direction has a continuous slope change, and a straight line having a different slope in the top of the cross section in the second direction. Can be. The second direction may be a direction perpendicular to the first direction. In addition, the second direction may be a direction having an arbitrary angle that is not perpendicular to the first direction.

An upper surface of the first conductivity-type semiconductor layer 11 according to the embodiment may include a repeated curved surface of a predetermined shape. For example, the upper surface of the first conductive semiconductor layer 11 may be implemented by repeating a wavy shape. In addition, various shapes such as spherical lens shape, concave lens shape, convex lens shape, and lenticular lens shape may be repeatedly provided on the upper surface of the first conductive semiconductor layer 11.

For example, when the curved surface having the concave spherical surface is formed on the upper surface of the first conductivity type semiconductor layer 11, the spherical slope having the height of about 1 to 2 micrometers is curved at a period of 10 to 50 micrometers. Can be formed.

As shown in FIG. 10, the unevenness 11a is formed on the upper surface of the first conductivity type semiconductor layer 11.

The unevenness 11a formed on the upper surface of the first conductivity type semiconductor layer 11 may be formed by, for example, a wet etching process. The unevenness 11a may be provided in a size of 0.8 to 1.2 micrometers in height. In addition, the period of the unevenness (11a) may be provided in the size of 0.8 to 1.2 micrometers. The cross section of the unevenness 11a may be formed in a triangular shape as an example. In addition, the spatial shape of the concave-convex 11a may be formed in a conical shape, a hexagonal pyramid shape, or the like. The shape of the unevenness 11a may be implemented in a shape in which the result of the etching rate difference is reflected in accordance with the characteristics of the crystal growth surface of the light emitting structure 10. For example, the triangular shape forming the cross section of the unevenness 11a may be formed such that a vertex protruding from the surface faces a vertical direction.

Subsequently, as illustrated in FIG. 11, isolation etching may be performed along boundaries of individual chips of the light emitting structure 10 to divide the plurality of light emitting devices into individual light emitting device units. The isolation etching can be performed by, for example, dry etching such as ICP (Inductively Coupled Plasma), but is not limited thereto.

Referring to FIG. 11, a protective layer 90 may be formed on at least a side surface of the light emitting structure 10. The protective layer 90 may prevent the light emitting structure 10 from being electrically shorted to an external electrode or the electrode 20.

The protective layer 90 may be formed of oxide or nitride. The protective layer 90 may be, for example, SiO ₂ , SiO _x , SiO _x N _y , Si ₃ N ₄ , Al ₂ O ₃ It may be formed of a material having a light transmitting and insulating properties. The protective layer 90 may be formed by, for example, a deposition method such as electron beam deposition, PECVD, and sputtering.

The electrode 20 is electrically connected to the light emitting structure 10. The electrode 20 may provide power to the light emitting structure 10 together with the reflective electrode 50, and may be formed to overlap at least a portion of the current blocking layer 31 in a vertical direction.

The transparent scattering particles 95 may be disposed in the form of a mono layer on the resin layer 97. The transparent scattering particles 95 may be mixed with the resin layer 97 and provided on the light emitting structure 10. The transparent scattering particles 85 may be embodied as small particles such that the absorption coefficient of the material is neglected. The transparent scattering particles 95 may be implemented to have a size of, for example, 100 nanometers to 20 micrometers. The transparent scattering particle 95 according to the embodiment scatters light incident in the direction of the light emitting structure 10. Accordingly, the light provided from the light emitting structure 10 is scattered and extracted to the outside to widen the directivity angle. That is, the light distribution pattern of the light emitting device can be widened. Accordingly, when applied to a light emitting device package including a phosphor, it is possible to widen the directivity angle and improve the white light conversion efficiency.

The method of forming the protective layer 90, the electrode 20, the resin layer 95, and the forming order described above may be variously modified according to embodiments.

12 is a view showing a light emitting device package to which the light emitting device according to the embodiment is applied.

Referring to FIG. 12, 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, which is provided to and electrically connected to the first lead electrode 31 and the second lead electrode 32, and the molding member 140 surrounding the light emitting device 100. 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, and 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 light emitted from the light emitting device 100.

A plurality of light emitting devices or light emitting device packages may be arranged on a substrate, and an optical member such as a lens, a light guide plate, a prism sheet, and a diffusion sheet may be disposed on an optical 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 as a top view or a side view type and may be provided in a display device such as a portable terminal and a notebook computer, or may be variously applied to a lighting device and a pointing device. Another embodiment may be implemented as a lighting device including the semiconductor light emitting device or the light emitting device package described in the above embodiments. For example, the lighting device may include a lamp, a streetlight, an electric signboard, and a headlight.

The light emitting device according to the embodiment may be applied to the light unit. The light unit may include a structure in which a plurality of light emitting elements are arranged, and may include the display device illustrated in FIGS. 13 and 14 and the lighting device illustrated in FIG. 15.

Referring to FIG. 13, the display device 1000 according to the embodiment includes a light guide plate 1041, a light emitting module 1031 providing light to the light guide plate 1041, and a reflective member 1022 under the light guide plate 1041. ), An optical sheet 1051 on the light guide plate 1041, a display panel 1061, a light guide plate 1041, a light emitting module 1031, and a reflective member 1022 on the optical sheet 1051. The bottom cover 1011 may be included, but is not limited thereto.

The bottom cover 1011, the reflective sheet 1022, the light guide plate 1041, and the optical sheet 1051 can be defined as a light unit 1050.

The light guide plate 1041 diffuses light to serve as a surface light source. The light guide plate 1041 is made of a transparent material, for example, acrylic resin-based such as polymethyl metaacrylate (PMMA), polyethylene terephthlate (PET), polycarbonate (PC), cycloolefin copolymer (COC), and polyethylene naphthalate (PEN). It may include one of the resins.

The light emitting module 1031 provides light to at least one side of the light guide plate 1041, and ultimately serves as a light source of the display device.

At least one light emitting module 1031 may be provided, and light may be provided directly or indirectly from one side of the light guide plate 1041. The light emitting module 1031 may include a substrate 1033 and a light emitting device 100 according to the embodiment described above. The light emitting devices 100 may be arranged on the substrate 1033 at predetermined intervals.

The substrate 1033 may be a printed circuit board (PCB) including a circuit pattern. However, the substrate 1033 may include not only a general PCB but also a metal core PCB (MCPCB, Metal Core PCB), a flexible PCB (FPCB, Flexible PCB) and the like, but is not limited thereto. When the light emitting device 100 is provided on the side surface of the bottom cover 1011 or the heat dissipation plate, the substrate 1033 may be removed. Here, a part of the heat dissipation plate may contact the upper surface of the bottom cover 1011.

The plurality of light emitting devices 100 may be mounted such that an emission surface from which light is emitted is spaced apart from the light guide plate 1041 by a predetermined distance, but is not limited thereto. The light emitting device 200 may directly or indirectly provide light to a light incident portion, which is one side of the light guide plate 1041, but is not limited thereto.

The reflective member 1022 may be disposed under the light guide plate 1041. The reflective member 1022 may improve the luminance of the light unit 1050 by reflecting light incident to the lower surface of the light guide plate 1041 and pointing upward. The reflective member 1022 may be formed of, for example, PET, PC, or PVC resin, but is not limited thereto. The reflective member 1022 may be an upper surface of the bottom cover 1011, but is not limited thereto.

The bottom cover 1011 may house the light guide plate 1041, the light emitting module 1031, the reflective member 1022, and the like. To this end, the bottom cover 1011 may be provided with a housing portion 1012 having a box-like shape with an opened upper surface, but the present invention is not limited thereto. The bottom cover 1011 may be combined with the top cover, but is not limited thereto.

The bottom cover 1011 may be formed of a metal material or a resin material, and may be manufactured using a process such as press molding or extrusion molding. In addition, the bottom cover 1011 may include a metal or a non-metal material having good thermal conductivity, but the present invention is not limited thereto.

The display panel 1061 is, for example, an LCD panel, including first and second transparent substrates facing each other, and a liquid crystal layer interposed between the first and second substrates. A polarizing plate may be attached to at least one surface of the display panel 1061, but the present invention is not limited thereto. The display panel 1061 displays information by light passing through the optical sheet 1051. The display device 1000 may be applied to various portable terminals, monitors of notebook computers, monitors of laptop computers, televisions, and the like.

The optical sheet 1051 is disposed between the display panel 1061 and the light guide plate 1041 and includes at least one light transmissive sheet. The optical sheet 1051 may include at least one of a sheet such as, for example, a diffusion sheet, a horizontal and vertical prism sheet, and a brightness enhancement sheet. The diffusion sheet diffuses the incident light, the horizontal and / or vertical prism sheet focuses the incident light into the display area, and the brightness enhancement sheet reuses the lost light to improve the brightness. A protective sheet may be disposed on the display panel 1061, but the present invention is not limited thereto.

Here, the optical path of the light emitting module 1031 may include the light guide plate 1041 and the optical sheet 1051 as an optical member, but the present invention is not limited thereto.

14 is a diagram illustrating another example of a display device according to an exemplary embodiment.

Referring to FIG. 14, the display device 1100 includes a bottom cover 1152, a substrate 1020 on which the light emitting device 100 disclosed above is arranged, an optical member 1154, and a display panel 1155.

The substrate 1020 and the light emitting device 100 may be defined as a light emitting module 1060. The bottom cover 1152, at least one light emitting module 1060, and the optical member 1154 may be defined as a light unit.

The bottom cover 1152 may include an accommodating part 1153, but is not limited thereto.

Here, the optical member 1154 may include at least one of a lens, a light guide plate, a diffusion sheet, a horizontal and vertical prism sheet, and a brightness enhancement sheet. The light guide plate may be made of a PC material or a poly methy methacrylate (PMMA) material, and the light guide plate may be removed. The diffusion sheet diffuses the incident light, the horizontal and vertical prism sheets focus the incident light onto the display area, and the brightness enhancement sheet reuses the lost light to improve the brightness.

The optical member 1154 is disposed on the light emitting module 1060, and performs surface light source, diffusion, condensing, etc. of the light emitted from the light emitting module 1060.

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

Referring to FIG. 15, the lighting device 1500 may include a case 1510, a light emitting module 1530 installed in the case 1510, and a connection terminal installed in the case 1510 and receiving power from an external power source. 1520).

The case 1510 may be formed of a material having good heat dissipation, and may be formed of, for example, a metal material or a resin material.

The light emitting module 1530 may include a substrate 1532 and a light emitting device 100 according to an embodiment provided on the substrate 1532. The plurality of light emitting devices 100 may be arranged in a matrix form or spaced apart at predetermined intervals.

The substrate 1532 may be a circuit pattern printed on an insulator. For example, a general printed circuit board (PCB), a metal core PCB, a flexible PCB, a ceramic PCB, FR-4 substrates and the like.

In addition, the substrate 1532 may be formed of a material that reflects light efficiently, or a surface may be coated with a color, for example, white or silver, in which the light is efficiently reflected.

At least one light emitting device 100 may be disposed on the substrate 1532. Each of the light emitting devices 100 may include at least one light emitting diode (LED) chip. The LED chip may include a colored light emitting diode emitting red, green, blue or white colored light, and a UV emitting diode emitting ultraviolet (UV) light.

The light emitting module 1530 may be disposed to have a combination of various light emitting devices 100 to obtain color and luminance. For example, a white light emitting diode, a red light emitting diode, and a green light emitting diode may be combined to secure high color rendering (CRI).

The connection terminal 1520 may be electrically connected to the light emitting module 1530 to supply power. The connection terminal 1520 is coupled to an external power source in a socket manner, but is not limited thereto. For example, the connection terminal 1520 may be formed in a pin shape and inserted into an external power source, or may be connected to the external power source by a wire.

According to the embodiment, after the light emitting device 200 is packaged, the light emitting device 200 may be mounted on the substrate to be implemented as a light emitting module, or may be mounted and packaged as an LED chip to be implemented as a light emitting module.

Features, structures, effects, and the like described in the above embodiments are included in at least one embodiment of the present invention, and are not necessarily limited to only one embodiment. Further, the features, structures, effects, and the like illustrated in the embodiments can be combined and modified by other persons having ordinary skill in the art to which the embodiments belong. Therefore, it should be understood that the present invention is not limited to these combinations and modifications.

In addition, the above description has been made with reference to the embodiments, which are merely exemplary and are not intended to limit the present invention. Those skilled in the art to which the present invention pertains will be illustrated above in the range without departing from the essential characteristics of the present embodiment. It will be appreciated that various modifications and applications are possible. For example, each component specifically shown in the embodiments can be modified and implemented. It is to be understood that all changes and modifications that come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

10 ... Light emitting structure 11 ... First conductive semiconductor layer
12 ... active layer 13 ... second conductive semiconductor layer
20 ... electrode 30 ... current blocking layer
40 ... ohmic contact layer 50 ... reflective electrode
60 ... bonding layer 70 ... conductive support member
80 ... Isolation Layer 90 ... Protective Layer
95 ... Transparent Scattering Particles 97 ... Resin Layer

Claims

A light emitting structure including a first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer;
An electrode disposed on the light emitting structure;
A reflective electrode disposed under the light emitting structure;
A resin layer disposed on the light emitting structure and including transparent scattering particles;
Light emitting device comprising a.

The light emitting device of claim 1, wherein the upper surface of the light emitting structure includes a curved surface having a continuous gradient change, and the uneven surface is provided on the upper surface of the light emitting structure.

The light emitting device of claim 1, wherein the upper surface of the light emitting structure includes a curve having a top slope of the cross section in the first direction and a curve having a top slope of the cross section in the second direction. .

The light emitting device of claim 1, wherein the upper surface of the light emitting structure includes a curved line having a continuous slope change in the upper portion of the cross section in the first direction, and a straight line having the different slopes in the upper portion of the cross section in the second direction.

The light emitting device of claim 2, wherein the unevenness is 0.8 to 1.2 micrometers in height.

A light emitting structure including a first conductive semiconductor layer, an active layer under the first conductive semiconductor layer, and a second conductive semiconductor layer under the active layer;
A first electrode electrically connected to the first conductive semiconductor layer;
A second electrode electrically connected to the second conductive semiconductor layer;
A resin layer disposed on the light emitting structure and including transparent scattering particles;
Light emitting device comprising a.

The light emitting device of claim 6, wherein an upper surface of the first conductive semiconductor layer includes a curved surface having a continuous gradient change, and an uneven surface is provided on the upper surface of the first conductive semiconductor layer.

The semiconductor device of claim 6, wherein the upper surface of the first conductivity-type semiconductor layer comprises a curve in which the top of the cross section in the first direction has a continuous slope change, and a curve in which the top of the cross section in the second direction has a continuous slope change. Light emitting device comprising.

The semiconductor device of claim 6, wherein the upper surface of the first conductivity-type semiconductor layer includes a curved line in which the top of the cross section in the first direction has a continuous slope change, and a straight line having a different slope in the top of the cross section in the second direction. Light emitting device.

The light emitting device of claim 6, wherein the unevenness is 0.8 to 1.2 micrometers in height.

The light emitting device according to claim 1 or 6, wherein the resin layer comprises epoxy or silicon.

The light emitting device of claim 1 or 6, wherein a refractive index of the transparent scattering particles has a larger value than that of the resin layer and a smaller value than that of the light emitting structure.

The light emitting device of claim 1 or 6, wherein the transparent scattering particles include a silicate-based material.

The light emitting device of claim 1, wherein the transparent scattering particles have a size of 100 nanometers to 20 micrometers.

Body;
A light emitting device disposed on the body and according to any one of claims 1 to 10;
A first lead electrode and a second lead electrode electrically connected to the light emitting element;
Light emitting device package comprising a.

Board;
A light emitting device disposed on the substrate and according to any one of claims 1 to 10;
An optical member through which light provided from the light emitting device passes;
Light unit comprising a.