KR20120086487A - Light emitting diode and method for fabricating the light emitting device - Google Patents

Abstract

PURPOSE: A light emitting device and a manufacturing method thereof are provided to improve light extraction efficiency by forming an inclined plane around the light emitting device. CONSTITUTION: A light emitting structure(120) is formed on a support substrate(160). The light emitting structure comprises a first conductivity type semiconductor layer(122), an active layer(124), and a second conductivity semiconductor layer(126). A barrier layer(180) is formed on a lower portion of the light emitting structure. A bonding layer(200) is formed on the lower portion of the barrier layer. A conductive layer(170) is formed on the lower portion of the barrier layer.

Description

Light emitting device and method for manufacturing the light emitting device

Embodiments relate to a light emitting device that enhances the adhesion of the light emitting device to improve stability and reliability.

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 relate to a light emitting device that improves the bonding strength of the light emitting device to improve the stability and reliability.

Embodiments include a light emitting structure including a first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer; A barrier layer formed under the light emitting structure; An adhesive layer formed under the barrier layer; Provided is a light emitting device including a conductive layer formed under the barrier layer.

In this case, the adhesive layer may be formed including copper (Cu) or gold (Au).

In addition, the thickness of the adhesive layer may be set to 0.1 ~ 4μm.

In addition, the barrier layer may include a channel layer or a current limiting layer.

The light emitting device may further include a reflective layer formed between the light emitting structure and the adhesive layer.

In addition, the light emitting device may further include an ohmic layer formed between the light emitting structure and the adhesive layer.

The light emitting device according to the embodiment has the effect of improving the bonding strength to improve the stability and reliability.

1 is a view showing an embodiment of a light emitting device,
2A to 2K are views illustrating 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 diffusion barrier layer 155 formed on the bonding layer 150, a conductive layer 170 formed on the diffusion barrier layer, and a conductive layer ( 170, the reflective layer 140 formed on the adhesive layer 200, the current limiting layer 135, the channel layer 180, the first conductive semiconductor layer 122, and the active layer 124. The light emitting structure 120 including the second conductive semiconductor layer 126, the first electrode 190 formed on the first conductive semiconductor layer 122, and the first conductive semiconductor layer 122. Passivation layer 195 to be included. Here, the current limiting layer 135 and the channel layer 180 formed on the adhesive layer 200 may be defined as a barrier layer.

As illustrated, the light emitting device may include a bonding layer 150, a diffusion barrier layer 155, and a conductive layer 170 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 using an electrochemical metal deposition method or a bonding method using a eutectic metal.

In addition, the bonding layer 150 may be formed on the support substrate 160 to be bonded to the diffusion barrier layer 155 or 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.

A diffusion barrier layer 155 may be formed on the bonding layer 150 to prevent the metal substrate constituting the support substrate 160 or the bonding layer 150 from diffusing into the light emitting structure 120 or the reflective layer 140. The diffusion barrier layer 155 may be formed of, for example, a material selected from the group consisting of copper (Cu), gold (Au), tin (Sn), and nickel (Ni) or an alloy thereof.

In some embodiments, the bonding layer 150 and the diffusion barrier layer 155 may be formed as one layer, and in some embodiments, the diffusion barrier layer 155 and the conductive layer 170 may be formed as one layer. .

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

An adhesive layer 200 may be formed on the conductive layer 170. The adhesive layer 200 may strengthen the adhesion between the barrier layer (the current limiting layer 135 or the channel layer 180) and the conductive layer 170. Prevents mechanical damage (breaking or peeling) of the light emitting device due to the weakening of adhesion between the barrier layer and the conductive layer 170, and alleviates the impact applied to the light emitting device during the manufacturing process of the light emitting device (eg, substrate separation, etc.). By minimizing mechanical damage (breaking or peeling) of the light emitting device, there is an effect that can increase the stability and reliability of the light emitting device. In this case, as described above, the current limiting layer 135 or the channel layer 180 may be defined as a barrier layer. In particular, when the barrier layer includes a material having a breaking property (for example, an insulating material, etc.), the adhesive layer 200 may have a large effect of increasing the adhesion between the barrier layer and the conductive layer.

 In addition, the adhesive layer 200 has an effect of preventing the metal material constituting the support substrate 160, the bonding layer 150, or the conductive layer 170 from being diffused into the light emitting structure 120.

The current blocking layer 135 distributes the flow of current flowing through the light emitting structure 120 in the horizontal direction, thereby preventing malfunction of the light emitting device due to overcurrent, thereby improving stability and reliability of the light emitting device.

The current blocking layer 135 may be formed between the adhesive layer 200 and the light emitting structure 120. The current blocking layer 135 may be formed using a material having a lower electrical conductivity than the reflective layer 140, a material forming a Schottky contact with the second conductive semiconductor layer 126, or an electrically insulating material. have. For example, the current blocking layer 135 may be formed of ZnO, SiO ₂ , SiON, It may include at least one of Si ₃ N ₄ , Al ₂ O _3, TiO ₂ , Ti, Al, Cr.

The current blocking layer 135 may be formed between the adhesive layer 200 and the second conductive semiconductor layer 126.

The channel layer 180 may include at least one of a metal material and an insulating material. In the case of a metal material, the channel layer 180 uses a material having a lower electrical conductivity than the material forming the ohmic layer 130 to be described later with reference to FIG. 3. It is possible to prevent the current applied to the 130 from being applied to the channel layer 180.

For example, the channel layer 180 may include at least one of titanium (Ti), nickel (Ni), platinum (Pt), lead (Pb), rhodium (Rh), iridium (Ir), and tungsten (W). Or at least one of aluminum oxide (Al ₂ O ₃ ), silicon oxide (SiO ₂ ), silicon nitride (Si ₃ N ₄ ), and titanium oxide (TiO _x ), or indium tin oxide (ITO) ), Aluminum zinc oxide (AZO) and indium zinc oxide (IZO, Indium Zinc Oxide) may include at least one, preferably titanium (Ti), nickel (Ni), platinum (Pt), It may include at least one of tungsten (W), molybdenum (Mo), vanadium (V), iron (Fe).

When the light emitting structure 120 is etched, the channel layer 180 protects the components disposed under the channel layer 180 from etching, and stably supports the light emitting device to protect against damages that may occur in the manufacturing process. .

The reflective layer 150 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 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. In this case, the uneven structure may be formed by using a dry etching process or by etching after forming a PEC method or a mask. The dry etching method may be used such as plasma etching, sputter etching, ion etching and the like.

The uneven structure of the light emitting structure changes the incident angle of and emitted from the active layer 124 to the first conductivity type semiconductor layer 122 to reduce the 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, a first electrode 190 is formed on the first conductive semiconductor layer 122, and the first electrode 190 is formed of molybdenum (Mo), chromium (Cr), nickel (Ni), and gold (Au). , Aluminum (Al), titanium (Ti), platinum (Pt), vanadium (V), tungsten (W), lead (Pd), copper (Cu), rhodium (Rh) and iridium (Ir) It consists of a metal or an alloy of these metals.

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

2A to 2G show a method of manufacturing the first embodiment of the 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 light emitting structure 120 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, the channel layer 180 is stacked on the second conductive semiconductor layer 126.

The channel layer 180 may include at least one of a metal material and an insulating material. In the case of a metal material, the channel layer 180 uses a material having a lower electrical conductivity than the material forming the ohmic layer 130 to be described later with reference to FIG. 3. It is possible to prevent the current applied to the 130 from being applied to the channel layer 180.

For example, the channel layer 180 may include at least one of titanium (Ti), nickel (Ni), platinum (Pt), lead (Pb), rhodium (Rh), iridium (Ir), and tungsten (W). Or at least one of aluminum oxide (Al ₂ O ₃ ), silicon oxide (SiO ₂ ), silicon nitride (Si ₃ N ₄ ), and titanium oxide (TiO _x ), or indium tin oxide (ITO) ), Aluminum zinc oxide (AZO) and indium zinc oxide (IZO, Indium Zinc Oxide) may include at least one, preferably titanium (Ti), nickel (Ni), platinum (Pt), It may include at least one of tungsten (W), molybdenum (Mo), vanadium (V), iron (Fe).

The channel layer 180 protects the components disposed below the channel layer 180 from etching during etching of the light emitting structure 120 to be described later, and stably supports the light emitting device to protect them from damage that may occur in the manufacturing process. There is.

The channel layer 180 is etched to form grooves. The groove may be formed by a dry etching process using a mask.

In addition, the current blocking layer 135 is formed in the groove formed as shown in FIG. 2C.

The current blocking layer 135 distributes the flow of current flowing through the light emitting structure 120 in the horizontal direction, thereby preventing malfunction of the light emitting device due to overcurrent, thereby improving stability and reliability of the light emitting device.

The current blocking layer 135 may be formed between the adhesive layer 200 and the light emitting structure 120. The current blocking layer 135 may be formed using a material having a lower electrical conductivity than the reflective layer 140, a material forming a Schottky contact with the second conductive semiconductor layer 126, or an electrically insulating material. have. For example, the current blocking layer 135 may be formed of ZnO, SiO ₂ , SiON, It may include at least one of Si ₃ N ₄ , Al ₂ O _3, TiO ₂ , Ti, Al, Cr.

The current blocking layer 135 may be formed between the adhesive layer 200 and the second conductive semiconductor layer 126.

2C, the reflective layer 140 is stacked on the second conductive semiconductor layer 126.

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 adhesive layer 200 is formed on the reflective layer 140, the current limiting layer 135, or the channel layer 180.

The adhesive layer 200 may include copper (Cu) or gold (Au). The adhesive layer 200 is an electron beam deposition method. It 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 some embodiments, the adhesive layer 200 may be formed of a plurality of layers.

According to the embodiment, the thickness of the adhesive layer 200 may be formed to be 0.1 to 4 μm.

The adhesive layer 200 strengthens the adhesive force between the current limiting layer 135 and the conductive layer 170 or between the channel layer 180 and the conductive layer 170, so that the current limiting layer 135 and the conductive layer 170 are formed. Or to prevent mechanical damage (breaking or peeling) of the light emitting device due to weakened adhesion between the channel layer 180 and the conductive layer 170, By mitigating the impact applied to minimize the mechanical damage (breaking or peeling) of the light emitting device, there is an effect that can increase the stability and reliability of the light emitting device.

In addition, the adhesive layer 200 has an effect of preventing the metal material constituting the support substrate 160, the bonding layer 150, or the conductive layer 170 from being diffused into the light emitting structure 120.

As illustrated in FIG. 2E, the conductive layer 170 is formed on the adhesive layer 200. The conductive layer 170 is selected from the group consisting of nickel (Ni-nickel), platinum (Pt), titanium (Ti), tungsten (W), vanadium (V), iron (Fe), and molybdenum (Mo). It can be made of materials or alloys in which they are optionally included.

In this case, the conductive layer 170 may be formed using a sputtering deposition method. When using a sputtering deposition method, when ionized atoms are accelerated by an electric field and impinge on the source material of layer 3 170, 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 supports the light emitting structure 120 as a whole, thereby minimizing mechanical damage (breaking or peeling, etc.) that may occur in the manufacturing process of the light emitting device.

As shown in FIG. 2F, a diffusion barrier layer 155 is formed on the conductive layer 170 to prevent the metal material forming the support substrate 160 or the bonding layer 150 from diffusing into the light emitting structure 120. Can be. The diffusion barrier layer 155 may be formed of, for example, a material selected from the group consisting of copper (Cu), gold (Au), tin (Sn), and nickel (Ni) or an alloy thereof.

In addition, the bonding layer 150 may be formed to bond the support substrate 160 and the diffusion barrier layer 155 or the support substrate 160 and 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.

In some embodiments, the bonding layer 150 and the diffusion barrier layer 155 may be formed as one layer, and in some embodiments, the diffusion barrier layer 155 and the conductive layer 170 may be formed as one layer. .

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 110 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, when a material forming the channel layer 180 is detected by an endpoint detecting method, a portion of the side surface of the light emitting structure 120 may be etched by stopping the etching.

At this time, the etching position may be adjusted so that the channel layer 180 is positioned under the light emitting structure 120 to be etched.

When the light emitting structure 120 is etched, the channel layer 180 protects the components disposed under the channel layer 180 from etching, and stably supports the light emitting device to protect against damages that may occur in the manufacturing process. .

In addition, an uneven structure is formed on the first conductive 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 to increase 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.

2J, a first electrode 190 may be formed on the first conductive semiconductor layer 122. The first electrode 190 may include molybdenum, chromium (Cr), and nickel ( Ni), gold (Au), aluminum (Al), titanium (Ti), platinum (Pt), vanadium (V), tungsten (W), lead (Pd), copper (Cu), rhodium (Rh) and iridium ( Ir) is made of any one metal or an alloy of the metals selected from.

As shown in FIG. 2K, a passivation layer 195 may be deposited on at least a portion of the channel layer 180, the side surface of the light emitting structure 120, and the first electrode 190. have. 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. As an 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.

3 illustrates an embodiment in which an ohmic layer 130 is added to the light emitting structure of FIG. 1. In this case, the ohmic layer 130 may be formed on the adhesive layer 2000 or the reflective layer 140, and may be formed on the light emitting structure 120, the channel layer 180, or the lower portion of the current limiting layer 135.

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 1300 may be formed by sputtering or electron beam deposition.

4 is a cross-sectional view of 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 on the 420 and electrically connected to the first electrode layer 411 and the second electrode layer 412, and a filler 440 surrounding the light emitting device 400 are included. do.

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 filler 440 may surround and protect the light emitting device 400. In addition, the filler 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 135: current limiting layer
140: reflective layer 150: bonding layer
155: diffusion barrier layer 160: support substrate
170: conductive layer 180: channel layer
190: first electrode 195: passivation layer
200: adhesive layer
400: light emitting element 411: first electrode layer
412: second electrode layer 420: package body
440: filling material

Claims (6)

A light emitting structure including a first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer;
A barrier layer formed under the light emitting structure;
An adhesive layer formed under the barrier layer; And
Light emitting device comprising a conductive layer formed under the barrier layer. The method of claim 1,
The adhesive layer is formed of copper (Cu) or gold (Au). The method of claim 1,
The thickness of the adhesive layer is a light emitting device is set to 0.1 ~ 4㎛. The method of claim 1,
The barrier layer includes a channel layer or a current limiting layer. The method of claim 1,
The light emitting device further comprises a reflective layer formed between the light emitting structure and the adhesive layer. The method of claim 1,
Light emitting device further comprises an ohmic layer formed between the light emitting structure and the adhesive layer.

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