KR20120086550A - Light emitting diode and method for fabricating the light emitting device - Google Patents

Abstract

PURPOSE: A light emitting diode and a fabricating method thereof are provided to efficiently etch a light emitting structure while protecting the light emitting device by forming an etching control layer on a lower edge portion of the light emitting structure. CONSTITUTION: A bonding layer(150) and a conductive layer(170) are formed on a support substrate(160). A metal channel layer(200) is formed into a structure of surrounding an ohmic layer(130) or a reflecting layer(140). The metal channel layer is formed by using sputtering deposition. An etching control layer(180) is formed on a lower edge portion of a light emitting structure(120). The light emitting structure comprises a first conductivity type semiconductor layer(122), an active layer(124), and a second conductivity type semiconductor layer(126).

Description

Light emitting device and method for manufacturing the light emitting device {Light emitting diode and method for fabricating the light emitting device}

Embodiments are directed to a light emitting device for effectively etching a light emitting structure while protecting the light emitting device when the light emitting structure is etched.

Light emitting devices such as light emitting diodes or laser diodes using semiconductors of Group 3-5 or 2-6 compound semiconductor materials of semiconductors have various colors such as red, green, blue and ultraviolet rays due to the development of thin film growth technology and device materials. It is possible to realize efficient white light by using fluorescent materials or combining colors, and it has low power consumption, semi-permanent life, fast response speed, safety and environmental friendliness compared to conventional light sources such as fluorescent and incandescent lamps. Has an advantage.

Therefore, a white light emitting device that can replace a fluorescent light bulb or an incandescent bulb that replaces a Cold Cathode Fluorescence Lamp (CCFL) constituting a backlight of a transmission module of an optical communication means and a liquid crystal display (LCD) display device. Applications are expanding to diode lighting devices, automotive headlights and traffic lights.

The stability and reliability of such a light emitting device is a very important factor, it is necessary to improve the stability and reliability of the light emitting device.

Embodiments are directed to a light emitting device for effectively etching a light emitting structure while protecting the light emitting device when the light emitting structure is etched.

Embodiments include a light emitting structure including a first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer; An ohmic layer positioned below the light emitting structure and having at least one opening to expose a portion of the lower part of the light emitting structure; And a metal channel layer surrounding the ohmic layer and filling the opening.

In this case, at least a part of the metal channel layer may be exposed to the side of the light emitting structure.

In addition, the metal channel layer may be formed of a material selected from the group of titanium (Ti), tungsten (W), titanium-tungsten (TiW), or an alloy containing them selectively.

In addition, the metal channel layer may have a thickness of about 1 nm to about 300 nm.

In addition, the ohmic layer may include an etching control layer formed at an edge of the lower surface of the light emitting structure.

In addition, the thickness of the etch control layer may be formed to 0.001 ~ 0.3 ㎛.

In addition, the etching control layer may be formed including indium tin oxide (ITO).

In addition, the etch control layer may be formed including indium tin oxide (Rapid Temperature Process) at a temperature of 400 ° C or more.

In addition, at least a portion of the metal channel layer formed on a side surface of the ohmic layer may be etched to expose the ohmic layer under the light emitting structure.

Another embodiment may include forming a light emitting structure including a first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer; Forming an ohmic layer under the light emitting structure; Forming at least one opening exposing a portion of the lower portion of the light emitting structure; And enclosing the ohmic layer and filling the opening to form a metal channel layer.

The light emitting device according to the embodiment has an effect of effectively etching the light emitting structure while protecting the light emitting device when the light emitting structure is etched.

1 is a view showing an embodiment of a light emitting device;
2A to 2K illustrate a method of manufacturing an embodiment of a light emitting device;
3 is a view showing another embodiment of a light emitting device;
4 is a view showing an embodiment of a light emitting device package.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

In the description of the above embodiments, each layer (region), region, pattern or structures may be "on" or "under" the substrate, each layer (layer), region, pad or pattern. In the case of what is described as being formed, "on" and "under" include both being formed "directly" or "indirectly" through another layer. In addition, the criteria for the top or bottom of each layer will be described with reference to the drawings.

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

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

As shown in FIG. 1. The light emitting device of the first embodiment includes a bonding layer 150 formed on the support substrate 160, a conductive layer 170 formed on the bonding layer 150, a metal channel layer 200 formed on the conductive layer 170, Ohmic layers 130 and 180 formed on the reflective layer 140, the reflective layer 140, and the metal channel layer 200, the first conductive semiconductor layer 122, the active layer 124, and the second conductive semiconductor layer ( The light emitting structure 120 including the 126 and the first electrode 190 formed on the first conductive semiconductor layer 122 are included.

As shown, the bonding layer 150 and the conductive layer 170 may be formed on the support substrate 160.

The support substrate 160 may be made of a material selected from the group consisting of molybdenum (Mo), silicon (Si), tungsten (W), copper (Cu), and aluminum (Al) or alloys thereof. For example, gold (Au), copper alloy (Cu Alloy), nickel (Ni-nickel), copper-tungsten (Cu-W), carrier wafers (e.g. GaN, Si, Ge, GaAs, ZnO, SiGe, SiC, SiGe, Ga ₂ O _3, etc.) may be optionally included. The conductive support substrate 160 may be formed by an electrochemical metal deposition method or a bonding method using a eutectic metal.

In addition, the coupling layer 150 may be formed on the support substrate 160 to couple the support substrate 160 to the conductive layer 170. The bonding layer 150 is, for example, from the group consisting of gold (Au), tin (Sn), indium (In), silver (Ag), nickel (Ni), niobium (Nb) and copper (Cu). It may be formed of the material selected or alloys thereof.

The conductive layer 170 is a material selected from the group consisting of nickel (Ni-nickel), platinum (Pt), titanium (Ti), tungsten (W), vanadium (V), iron (Fe), and molybdenum (Mo). Or they may be made of an alloy optionally included.

The conductive layer 170 can be formed using a sputtering deposition method. When using the sputtering deposition method, when ionized atoms are accelerated by an electric field and collide with the source material of the conductive layer 170, the atoms of the source material are ejected and deposited. In addition, according to the embodiment, an electrochemical metal deposition method, a bonding method using a eutectic metal, or the like may be used. In some embodiments, the conductive layer 170 may be formed of a plurality of layers.

The conductive layer 170 has an effect of minimizing mechanical damage (breaking or peeling, etc.) that may occur in the manufacturing process of the light emitting device.

In addition, the conductive layer 170 has an effect of preventing the metal material constituting the support substrate 160 or the bonding layer 150 from being diffused into the light emitting structure 120.

The metal channel layer 200 may be formed to surround the ohmic layers 130 and 180 or the reflective layer 140, and at least a portion thereof may be exposed to the side surface of the light emitting structure 120.

That is, the metal channel layer 200 may be formed to surround the ohmic layers 130 and 180 having at least one or more openings exposing a portion of the lower portion of the light emitting structure 120 and filling the openings.

The metal channel layer 200 may include a material that is effectively etched in the wet etching process performed on the side surface of the light emitting structure 120 to be described later. For example, titanium (Ti), tungsten (W), or titanium- It may be made of a material selected from the group of tungsten (TiW) or an alloy containing them selectively, the thickness may be formed from 0.001 ~ 0.3 ㎛. For example, when the etchant used in the wet etching process performed on the side of the light emitting structure 120 is a mixture of ammonia and hydrofluoric acid (HF), titanium (Ti) may be included in the metal channel layer 200.

The metal channel layer 200 may be formed using a sputtering deposition method, and when using the sputtering deposition method, the ionized atoms are accelerated by an electric field to collide with the source material of the metal channel layer 170. As a result, atoms of the source material stick out and deposit. In addition, according to the embodiment, an electrochemical metal deposition method, a bonding method using a eutectic metal, or the like may be used.

The metal channel layer 200 may be effectively etched during the wet etching process of the light emitting structure 120 to be described later to effectively remove foreign substances formed on the side of the light emitting structure.

In addition, the etching control layer 180 formed at the edge of the lower surface of the light emitting structure 120 among the ohmic layers 130 and 180 is overetched to the side of the light emitting structure 120 during the wet etching process of the light emitting structure 120 to be described later. It is prevented to protect the components located on the side or the bottom of the etch control layer 180 from the wet etching process, and there is an effect of protecting the light emitting device in a stable manner from damage that may occur in the manufacturing process.

The etching control layer 180 may include a material that minimizes etching for the etching liquid used in the wet etching of the side surface of the light emitting structure 120.

In addition, the etch control layer 180 includes a material that minimizes etching for the etchant used during the wet etching of the side surface of the light emitting structure, and is made of a material forming ohmic contact with the second conductive semiconductor layer 126. The role of the mix layer 130 may be simultaneously performed.

For example, indium tin oxide (ITO), indium zinc oxide (IZO), indium zinc tin oxide (IZTO), indium aluminum zinc oxide (IAZO), indium gallium zinc oxide (IGZO), indium gallium tin oxide (IGTO), Aluminum zinc oxide (AZO), antimony tin oxide (ATO), gallium zinc oxide (GZO), IZO (IZO Nitride), AGZO (Al-Ga ZnO), IGZO (In-Ga ZnO), ZnO, IrOx, RuOx, NiO , RuOx / ITO, Ni / IrOx / Au, and Ni / IrOx / Au / ITO, Ag, Ni, Cr, Ti, Al, Rh, Pd, Ir, Sn, In, Ru, Mg, Zn, Pt, Au, It may be formed including at least one of Hf, but is not limited to such materials. The ohmic layer 130 may be formed by sputtering or electron beam deposition.

For example, the etch control layer 180 may include indium tin oxide (ITO), and may have a thickness of 0.001 to 0.3 μm.

In this case, the etch control layer 180 may be formed to include indium tin oxide (ITO) that has undergone a rapid temperature process (Rapid Temperature Process) process at a temperature of 400 ° C or more.

In some embodiments, the metal channel layer 200 formed on the side of the etch control layer 180 may be partially etched to expose the etch control layer 180 under the light emitting structure 120.

Therefore, the light emitting device of the embodiment includes a metal channel layer 180, so that when performing a wet etching process on the side of the light emitting structure 120, foreign matter formed on the side of the light emitting structure can be effectively removed, the etching control layer Including the 180, the wet etching process of the light emitting structure 120, to prevent over-etching to the side of the light emitting structure 120 to protect the components located on the side or the bottom of the etching control layer 180 from the wet etching process It can work.

The reflective layer 140 may be made of a metal layer including aluminum (Al), silver (Ag), nickel (Ni), platinum (Pt), rhodium (Rh), or an alloy containing Al, Ag, Pt, or Rh. . Aluminum or silver may effectively reflect light generated from the active layer 124 to greatly improve the light extraction efficiency of the light emitting device.

The ohmic layer 130 may be stacked to a thickness of about 200 angstroms. The ohmic layer 130 may selectively use a light transmissive conductive layer and a metal. For example, indium tin oxide (ITO), indium zinc oxide (IZO), indium zinc tin oxide (IZTO), and indium aluminum zinc (AZO) oxide), IGZO (indium gallium zinc oxide), IGTO (indium gallium tin oxide), AZO (aluminum zinc oxide), ATO (antimony tin oxide), GZO (gallium zinc oxide), IZON (IZO Nitride), AGZO (Al- Ga ZnO), IGZO (In-Ga ZnO), ZnO, IrOx, RuOx, NiO, RuOx / ITO, Ni / IrOx / Au, and Ni / IrOx / Au / ITO, Ag, Ni, Cr, Ti, Al, Rh , Pd, Ir, Sn, In, Ru, Mg, Zn, Pt, Au, can be formed including at least one of Hf, and is not limited to these materials. The ohmic layer 130 may be formed by sputtering or electron beam deposition.

The first conductivity-type semiconductor layer 122 may be implemented as a group III-V compound semiconductor doped with a first conductivity type dopant, and the first conductivity type semiconductor layer 112 may be an N-type semiconductor layer. In this case, the first conductivity type dopant may be an N type dopant and may include Si, Ge, Sn, Se, Te, but is not limited thereto.

In addition, the active layer 124 may be formed by integrating electrons injected through the first conductivity-type semiconductor layer 122 and holes injected through the second conductivity-type semiconductor layer 126 that are formed thereafter to form an active layer (light emitting layer) material. It is a layer that emits light with energy determined by the energy band.

The second conductivity-type semiconductor layer 126 may be a Group III _- V compound semiconductor doped with a second conductivity type dopant, for example, In _x Al _y Ga _1-xy N (0 ≦ x ≦ 1, 0 ≦ y ≦ And 1, 0 ≦ x + y ≦ 1). When the second conductive semiconductor layer 126 is a P-type semiconductor layer, the second conductive dopant may include Mg, Zn, Ca, Sr, Ba, and the like as a P-type dopant.

An uneven structure is formed on the first conductive semiconductor layer 122 to improve light extraction efficiency.

The uneven structure of the light emitting structure changes the incident angle of light emitted from the active layer 124 to the first conductivity type semiconductor layer 122 to reduce total reflection on the surface of the first conductivity type semiconductor layer 122 to extract light. The effect can be increased, and the luminous efficiency of the light emitted from the active layer 124 can be reduced by reducing the absorption of the light in the light emitting structure.

The uneven structure may be formed periodically or aperiodically, and the uneven shape is not limited. For example, the concave-convex shape includes all shapes of single or complex shapes such as square, hemisphere, triangle, and trapezoid.

The uneven structure may be formed using a wet etching process or a dry etching process, or may be formed using a wet etching process and a dry etching process.

The dry etching method may be plasma etching, sputter etching, ion etching, etc., and the wet etching process may be a PEC (Photo Chemical Wet-etching) process.

At this time, in the case of the PEC process, by adjusting the amount of the etching liquid (eg, KOH) and the etching rate difference by the GaN crystallinity, it is possible to control the shape of the irregularities of the fine size. After the mask is formed, the uneven shape may be periodically adjusted through etching.

In addition, first electrodes 190 and 195 are formed on the first conductive semiconductor layer 122, and the first electrodes 190 and 195 may include molybdenum (Mo), chromium (Cr), nickel (Ni), Among gold (Au), aluminum (Al), titanium (Ti), platinum (Pt), vanadium (V), tungsten (W), lead (Pd), copper (Cu), rhodium (Rh) and iridium (Ir) It is made of any one metal or alloy of the metals selected.

Detailed description of each configuration will be described in detail with reference to FIGS. 2A to 2G.

2A to 2K illustrate a method of manufacturing an embodiment of a light emitting device.

The substrate 100 is prepared as shown in FIG. 2A. The substrate 100 may be formed of a conductive substrate or an insulating substrate. For example, sapphire (Al ₂ O ₃ ), SiC, Si, GaAs, GaN, ZnO, Si, GaP, InP, Ge, and Ga ₂ 0 At least one of _three may be used. An uneven structure may be formed on the substrate 100, but is not limited thereto. Impurities on the surface may be removed by wet cleaning the substrate 100.

In addition, the light emitting structure 120 including the first conductive semiconductor layer 122, the active layer 124, and the second conductive semiconductor layer 126 may be formed on the substrate 100.

In this case, a buffer layer (not shown) may be grown between the first conductivity type semiconductor layer 122 and the substrate 100 to mitigate the difference in lattice mismatch and thermal expansion coefficient of the material. The material of the buffer layer may be made of a group III-V compound semiconductor, and for example, may be formed of at least one of GaN, InN, AlN, InGaN, AlGaN, InAlGaN, and AlInN. An undoped semiconductor layer may be formed on the buffer layer, but is not limited thereto.

In addition, the light emitting structure 120 may include, for example, a metal organic chemical vapor deposition (MOCVD), a chemical vapor deposition (CVD), or a plasma chemical vapor deposition (PECVD). ), Molecular Beam Epitaxy (MBE), Hydride Vapor Phase Epitaxy (HVPE), and the like, but are not limited thereto.

The first conductive semiconductor layer 122 may be implemented as a group III-V compound semiconductor doped with a first conductive dopant, and the first conductive semiconductor layer 112 is an N-type semiconductor layer. The first conductive dopant may be an N-type dopant, and may include, for example, Si, Ge, Sn, Se, or Te.

The first conductive semiconductor layer 122 may be formed of a semiconductor material having a composition formula of Al _x In _y Ga _(1-xy) N (0 ≦ x ≦ 1, 0 ≦ y ≦ 1, 0 ≦ x + y ≦ 1). It may include. For example, the first conductive semiconductor layer 112 may be formed of any one or more of GaN, InN, AlN, InGaN, AlGaN, InAlGaN, AlInN, AlGaAs, InGaAs, AlInGaAs, GaP, AlGaP, InGaP, AlInGaP, InP. Can be.

The first conductive semiconductor layer 122 may include a silane gas containing n-type impurities such as trimethyl gallium gas (TMGa), ammonia gas (NH ₃ ), nitrogen gas (N ₂ ), and silicon (Si) in the chamber. SiH ₄ ) may be implanted.

The active layer 124 has energy determined by an energy band inherent in the active layer (light emitting layer) material because carriers injected through the first conductive semiconductor layer 122 and the second conductive semiconductor layer 126 meet each other. It is a layer that emits light.

The active layer 124 may be formed of at least one of a single quantum well structure, a multi quantum well structure (MQW), a quantum-wire structure, or a quantum dot structure. For example, the active layer 114 may be formed by injecting trimethyl gallium gas (TMGa), ammonia gas (NH ₃ ), nitrogen gas (N ₂ ), and trimethyl indium gas (TMIn) to form a multi-quantum well structure. It is not limited to this.

The well layer / barrier layer of the active layer 124 has a pair structure of at least one of InGaN / GaN, InGaN / InGaN, GaN / AlGaN /, InAlGaN / GaN, GaAs (InGaAs), / AlGaAs, GaP (InGaP) / AlGaP. It may be formed, but is not limited thereto. The well layer may be formed of a material having a band gap narrower than the band gap of the barrier layer.

A conductive cladding layer (not shown) may be formed on or under the active layer 124. The conductive clad layer may be formed of an AlGaN-based semiconductor, and may have a band gap higher than that of the active layer 124.

The second conductivity-type semiconductor layer 126 may be a Group III-V compound semiconductor doped with a second conductivity type dopant, for example, In _x Al _y Ga _1-xy N (0 ≦ x ≦ 1, 0 ≦ y ≦ 1, Semiconductor material having a composition formula of 0 ≦ x + y ≦ 1). When the second conductivity type semiconductor layer 126 is a P type semiconductor layer, the second conductivity type dopant may include Mg, Zn, Ca, Sr, Ba, or the like as a P type dopant.

The second conductivity type semiconductor layer 126 is a bicetyl cyclone containing p-type impurities such as trimethyl gallium gas (TMGa), ammonia gas (NH ₃ ), nitrogen gas (N ₂ ), and magnesium (Mg) in the chamber. Pentadienyl magnesium (EtCp ₂ Mg) {Mg (C ₂ H ₅ C ₅ H ₄ ) ₂ } may be injected to form a p-type GaN layer, but is not limited thereto.

In an embodiment, the first conductive semiconductor layer 122 may be a P-type semiconductor layer, and the second conductive semiconductor layer 126 may be an N-type semiconductor layer. In addition, an N-type semiconductor layer (not shown) may be formed on the second conductive semiconductor layer 126 when the semiconductor having a polarity opposite to that of the second conductive type, for example, the second conductive semiconductor layer is a P-type semiconductor layer. have. Accordingly, the light emitting structure 110 may be implemented as any one of an N-P junction structure, a P-N junction structure, an N-P-N junction structure, and a P-N-P junction structure.

As illustrated in FIG. 2B, an etch control layer 180 is formed on the second conductive semiconductor layer 126. The etching control layer 180 refers to a layer formed at an edge of the bottom surface of the light emitting structure 120 among the ohmic layers 130 and 180.

The etch control layer 180 prevents overetching to the side of the light emitting structure 120 during the wet etching process of the light emitting structure 120, which will be described later, to wet etch components disposed on the side or the bottom of the etch control layer 180. There is an effect of protecting from the process, and stably supporting the light emitting device to protect from damage that may occur in the manufacturing process.

The etching control layer 180 may include a material that minimizes etching for the etching liquid used in the wet etching of the side surface of the light emitting structure 120.

In addition, the etching solution used for wet etching of the side surface of the light emitting structure includes a material that minimizes etching, and is formed of a material forming an ohmic contact with the second conductive semiconductor layer 126 to serve as the ohmic layer 130. Can also be done at the same time.

For example, the etch control layer 180 may include indium tin oxide (ITO), and may have a thickness of 0.001 to 0.3 μm.

In this case, the etch control layer 180 may be formed to include indium tin oxide (ITO) that has undergone a rapid temperature process at a temperature of 400 ° C. or higher.

In some embodiments, the metal channel layer 200 formed on the side of the etch control layer 180 may be partially etched to expose the etch control layer 180 under the light emitting structure 120.

As shown in FIG. 2C, the ohmic layer 130 and the reflective layer 140 are formed.

In this case, the ohmic layer 130 may be stacked to a thickness of about 200 angstroms. The ohmic layer 130 may selectively use a light transmissive conductive layer and a metal. For example, indium tin oxide (ITO), indium zinc oxide (IZO), indium zinc tin oxide (IZTO), and indium aluminum zinc (AZO) oxide), IGZO (indium gallium zinc oxide), IGTO (indium gallium tin oxide), AZO (aluminum zinc oxide), ATO (antimony tin oxide), GZO (gallium zinc oxide), IZON (IZO Nitride), AGZO (Al- Ga ZnO), IGZO (In-Ga ZnO), ZnO, IrOx, RuOx, NiO, RuOx / ITO, Ni / IrOx / Au, and Ni / IrOx / Au / ITO, Ag, Ni, Cr, Ti, Al, Rh , Pd, Ir, Sn, In, Ru, Mg, Zn, Pt, Au, can be formed including at least one of Hf, and is not limited to these materials. The ohmic layer 130 may be formed by sputtering or electron beam deposition.

The reflective layer 140 can be formed to a thickness of about 2500 angstroms. The reflective layer 140 may be formed of, for example, a metal or an alloy including at least one of Ag, Ni, Al, Rh, Pd, Ir, Ru, Mg, Zn, Pt, Au, or Hf. Alternatively, the metal or alloy may be formed in a multilayer using light transmitting conductive materials such as ITO, IZO, IZTO, IAZO, IGZO, IGTO, AZO, and ATO, and specifically, IZO / Ni, AZO / Ag, and IZO. / Ag / Ni, AZO / Ag / Ni, Ag / Cu, Ag / Pd / Cu and the like can be laminated. Aluminum or silver may effectively reflect light generated from the active layer 124 to greatly improve the light extraction efficiency of the light emitting device.

As shown in FIG. 2D, the metal channel layer 200 is formed on the ohmic layer 130, the reflective layer 140, or the etch control layer 180.

The metal channel layer 200 may be formed to surround the etch control layer 180, the ohmic layer 130, or the reflective layer 140, and at least a portion thereof may be exposed to the side surface of the light emitting structure 120. That is, the metal channel layer 200 may be formed by surrounding the ohmic layers 130 and 180 having at least one or more openings exposing a portion of the upper portion of the light emitting structure 120 and filling the openings.

The metal channel layer 200 may include a material that is effectively etched in the wet etching process performed on the side surface of the light emitting structure 120 to be described later. For example, titanium (Ti), tungsten (W), or titanium- It may be made of a material selected from the group of tungsten (TiW) or an alloy containing these selectively. In addition, the thickness of the metal channel layer 200 may be formed to 0.001 ~ 0.3 ㎛.

The metal channel layer 200 may be formed using a sputtering deposition method, and when using the sputtering deposition method, the ionized atoms are accelerated by an electric field to collide with the source material of the metal channel layer 170. As a result, atoms of the source material stick out and deposit. In addition, according to the embodiment, an electrochemical metal deposition method, a bonding method using a eutectic metal, or the like may be used.

The metal channel layer 200 may be effectively etched during the wet etching process of the light emitting structure 120 to be described later to effectively remove foreign substances formed on the side of the light emitting structure.

As shown in FIG. 2E, the conductive layer 170 is formed on the metal channel layer 200. The conductive layer 170 is a material selected from the group consisting of nickel (Ni-nickel), platinum (Pt), titanium (Ti), tungsten (W), vanadium (V), iron (Fe), and molybdenum (Mo). Or they may be made of an alloy optionally included.

The conductive layer 170 may be formed using a sputtering deposition method. When using the sputtering deposition method, when the ionized atoms are accelerated by an electric field and collide with the source material of the conductive layer 170, Atoms of the source material stick out and deposit. In addition, according to the embodiment, an electrochemical metal deposition method, a bonding method using a eutectic metal, or the like may be used. In some embodiments, the conductive layer 170 may be formed of a plurality of layers.

The conductive layer 170 has an effect of minimizing mechanical damage (breaking or peeling, etc.) that may occur in the manufacturing process of the light emitting device. In addition, the conductive layer 170 has an effect of preventing the metal material constituting the support substrate 160 or the bonding layer 150 from being diffused into the light emitting structure 120.

As shown in FIG. 2F, a bonding layer 150 may be formed to couple the support substrate 160 to the conductive layer 170. The bonding layer 150 is, for example, from the group consisting of gold (Au), tin (Sn), indium (In), silver (Ag), nickel (Ni), niobium (Nb) and copper (Cu). It may be formed of the material selected or alloys thereof.

And as shown in FIG. 2G. The support substrate 160 may be formed on the bonding layer 150.

The support substrate 160 may be made of a material selected from the group consisting of molybdenum (Mo), silicon (Si), tungsten (W), copper (Cu), and aluminum (Al) or alloys thereof. For example, gold (Au), copper alloy (Cu Alloy), nickel (Ni-nickel), copper-tungsten (Cu-W), carrier wafers (e.g. GaN, Si, Ge, GaAs, ZnO, SiGe, SiC) , SiGe, Ga ₂ O _3, etc.) may be optionally included. The conductive support substrate 160 may be formed using an electrochemical metal deposition method or a bonding method using a eutectic metal.

In some embodiments, when holes are injected into the second conductive semiconductor layer 126 through the conductive layer 170, the support substrate 160 may be made of an insulating material. It may be made of nitride. For example, the support substrate 160 may include a silicon oxide (SiO ₂ ) layer, an oxynitride layer, and an aluminum oxide layer.

And, as shown in Figure 2h, the substrate 100 is separated.

The substrate 100 may be removed by a laser lift off (LLO) method using an excimer laser or the like, or may be a dry or wet etching method.

For example, when the laser lift-off method focuses and irradiates excimer laser light having a predetermined wavelength toward the substrate 100, thermal energy is applied to the interface between the substrate 100 and the light emitting structure 120. As the interface is concentrated and separated into gallium and nitrogen molecules, separation of the substrate 100 occurs at a portion where the laser light passes.

As shown in FIG. 2I, the side surface of the light emitting structure 120 is etched. In this case, the side etching of the light emitting structure 120 may use a dry etching process or a wet etching process, or may use a dry etching process and a wet etching process.

The dry etching method may be plasma etching, sputter etching, ion etching, etc., and the wet etching process may be a PEC (Photo Chemical Wet-etching) process, a buffer oxide etching (BOE) process, or the like.

When both the dry etching process and the wet etching process are used, the side of the light emitting structure 120 may be etched by the dry etching process, and foreign matter remaining on the side of the light emitting structure 120 may be removed through the wet etching process.

In this case, since the metal channel layer 200 includes a material that is effectively etched during the wet etching process, the foreign material remaining on the side of the light emitting structure is effectively etched during the wet etching process performed on the side of the light emitting structure 120. There is an effect that can be effectively removed.

For example, when the etching solution is subjected to a BOE (Buffer Oxide etching) process in which a mixture of ammonia and hydrofluoric acid (HF) is used, titanium (Ti) may be included in the metal channel layer 200.

In addition, since the etching control layer 180 is formed by including a material that minimizes the etching of the etching liquid used in the wet etching of the side of the light emitting structure 120, the wet of the light emitting structure 120 During the etching process, the components on the side or the bottom of the etch control layer 180 are prevented from being over-etched to the side of the light emitting structure 120 from the wet etching process, and the light emitting device is stably supported so that the light emitting device may be generated in the manufacturing process. It protects against possible damage.

In this case, the etch control layer 180 is formed of a material forming an ohmic contact with the second conductivity-type semiconductor layer 126 while including a material that minimizes etching for the etchant used during the wet etching of the side of the light emitting structure. As described above, the role of the ohmic layer 130 may be simultaneously performed.

Therefore, the light emitting device of the embodiment includes a metal channel layer 180, when performing a wet etching process on the side of the light emitting structure 120, while effectively removing foreign substances formed on the side of the light emitting structure 120, In the wet etching process of the light emitting structure 120 including the etch control layer 180, wet etching of the components disposed on the side or the bottom of the etch control layer 180 is prevented from being over-etched to the side of the light emitting structure 120. There is an effect that can be protected from the process.

As shown in FIG. 2J, an uneven structure is formed on the first conductivity-type semiconductor layer 122 to improve light extraction efficiency.

The uneven structure changes the angle of incidence of the light emitted from the active layer 124 to enter the first conductivity type semiconductor layer 122, thereby reducing the total reflection on the surface of the first conductivity type semiconductor layer 122, thereby increasing the light extraction effect. It is possible to reduce the absorption of light emitted from the active layer 124 in the light emitting structure, thereby increasing the luminous efficiency.

The uneven structure may be formed periodically or aperiodically, and the uneven shape is not limited. For example, the concave-convex shape includes all shapes of single or complex shapes such as square, hemisphere, triangle, and trapezoid.

The uneven structure may be formed using a wet etching process or a dry etching process, or may be formed using a wet etching process and a dry etching process.

The dry etching method may be plasma etching, sputter etching, ion etching, etc., and the wet etching process may be a PEC (Photo Chemical Wet-etching) process.

At this time, in the case of the PEC process, by adjusting the amount of the etching liquid (eg, KOH) and the etching rate difference by the GaN crystallinity, it is possible to control the shape of the irregularities of the fine size. After the mask is formed, the uneven shape may be periodically adjusted through etching.

Even when the wet etching process is performed when the uneven structure is formed on the first conductive semiconductor 122, as described above with reference to FIG. 2I, the foreign material formed on the side surface 201 of the light emitting structure 120 may be the metal channel layer 200. Can be effectively removed, and also prevented from overetching the side of the light emitting structure 120 by the etch control layer 180 to protect components located on the side or bottom of the etch control layer 180. It works.

2K, a first electrode 190 may be formed on the first conductivity-type semiconductor layer 122. The first electrodes 190 and 195 may include molybdenum, chromium (Cr), Nickel (Ni), Gold (Au), Aluminum (Al), Titanium (Ti), Platinum (Pt), Vanadium (V), Tungsten (W), Lead (Pd), Copper (Cu), Rhodium (Rh) and It is made of any one metal selected from iridium (Ir) or an alloy of the metals.

In some embodiments, a passivation layer may be deposited on at least a portion of the metal channel layer 200, the light emitting structure 120, and the first electrode 190. Here, the passivation layer may be made of an insulating material, and the insulating material may be made of an oxide or nitride which is non-conductive. For example, the passivation layer may be formed of a silicon oxide (SiO ₂ ) layer, an oxynitride layer, or an aluminum oxide layer.

3 is a view showing another embodiment of a light emitting structure.

In some embodiments, the metal channel layer 200 formed on the side of the etch control layer 180 among the ohmic layers 130 and 180 of the light emitting device is partially etched so that the etch control layer 180 is lowered to the lower portion of the light emitting structure 120. May be exposed. This may be a result of the wet etching process of the light emitting structure 120 of FIG. 2I.

At this time, the foreign matter formed on the side surface 301 of the light emitting structure 120 can be effectively removed by the metal channel layer 200, and also over the side of the light emitting structure 120 by the etching control layer 180. It can be seen that there is an effect that the etching is prevented so that the components located on the side or the bottom of the etching control layer 180 can be protected.

4 is a diagram illustrating an embodiment of a light emitting device package.

As shown, the light emitting device package according to the above-described embodiments, the package body 420, the first electrode layer 411 and the second electrode layer 412 provided on the package body 420, and the package body ( The light emitting device 400 according to the embodiment installed in the 420 and electrically connected to the first electrode layer 411 and the second electrode layer 412, and the resin layer 440 surrounding the light emitting device 400 are provided. Include.

The package body 420 may include a silicon material, a synthetic resin material, or a metal material. An inclined surface may be formed around the light emitting device 400 to increase light extraction efficiency.

The first electrode layer 411 and the second electrode layer 412 are electrically separated from each other, and provide power to the light emitting device 400. In addition, the first electrode layer 411 and the second electrode layer 412 can increase the light efficiency by reflecting the light generated from the light emitting device 400, the outside of the heat generated from the light emitting device 400 May also act as a drain.

The light emitting device 400 may be installed on the package body 420 or on the first electrode layer 411 or the second electrode layer 412.

The light emitting device 400 may be electrically connected to the first electrode layer 411 and the second electrode layer 412 by any one of a wire method, a flip chip method, and a die bonding method.

The resin layer 440 may surround and protect the light emitting device 400. In addition, the resin layer 440 may include a phosphor to change the wavelength of light emitted from the light emitting device 400.

The light emitting device package may mount at least one of the light emitting devices of the above-described embodiments as one or more, but is not limited thereto.

A plurality of light emitting device packages according to the embodiment may be arranged on a substrate, and a light guide plate, a prism sheet, a diffusion sheet, or the like, which is an optical member, 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. Another embodiment may be implemented as a display device, an indicator device, or a lighting system including the semiconductor light emitting device or the light emitting device package described in the above embodiments, for example, the lighting system may include a lamp and a street lamp. .

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. 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 understood that the present invention is not limited to these combinations and modifications.

100: substrate
120: light emitting structure 122: first conductive semiconductor layer
124: active layer 126: second conductive semiconductor layer
130: ohmic layer 140: reflective layer
150: bonding layer 160: supporting substrate
170: conductive layer 180: etching control layer
190: first electrode 200: metal channel layer
400: light emitting element 411: first electrode layer
412: second electrode layer 420: package body
440: resin layer

Claims (10)

A light emitting structure including a first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer;
Located under the light emitting structure,
An ohmic layer in which at least one opening is formed to expose a portion of the lower portion of the light emitting structure; And
A metal channel layer covering the ohmic layer and filling the opening
Light emitting device comprising a. The method of claim 1,
At least a portion of the metal channel layer is exposed to a side of the light emitting structure. The method of claim 1,
The metal channel layer is formed of a material selected from the group of titanium (Ti), tungsten (W), titanium-tungsten (TiW) or an alloy containing them selectively. The method of claim 1,
The metal channel layer has a thickness of 1 ~ 300nm formed light emitting device. The method of claim 1,
The ohmic layer includes an etch control layer formed on the bottom edge of the light emitting structure. The method of claim 5,
The thickness of the etching control layer is a light emitting device is formed in 0.001 ~ 0.3 ㎛. The method of claim 5,
The etching control layer is a light emitting device is formed including indium tin oxide (ITO). The method of claim 6,
The etch control layer is formed of light emitting devices including indium tin oxide (Rapid Temperature Process) heat treatment at a temperature of 400 ° C or more. The method of claim 1,
At least a portion of the metal channel layer formed on the side of the ohmic layer is etched so that the ohmic layer is exposed to the lower portion of the light emitting structure. Forming a light emitting structure including a first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer;
Forming an ohmic layer under the light emitting structure;
Forming at least one opening exposing a portion of the lower portion of the light emitting structure; And
And covering the ohmic layer and filling the opening to form a metal channel layer.

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