KR20120046374A - Light emitting device - Google Patents

Abstract

PURPOSE: A light emitting device is provided to improve luminous efficiency by emitting a first light emitting device of a horizontal type and a second light emitting device of a vertical type. CONSTITUTION: A light emitting structure(120) is formed on a substrate(100). An ohmic layer(130) and a reflecting layer(140) are formed on a second conductive semiconductor layer. A conductive layer(150) is formed on the reflecting layer. A bonding layer(160) is formed on the conductive layer. A conductive supporting substrate(270) is placed on the bonding layer. A second light emitting structure(220) is formed on the conductive supporting substrate.

Description

Light Emitting Device {LIGHT EMITTING DEVICE}

The embodiment relates to a light emitting device.

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 embodiment is intended to improve the light efficiency of the light emitting device.

Embodiments may include a first light emitting structure including a first conductive semiconductor layer, an active layer, a second conductive semiconductor layer, and a first electrode on the first conductive semiconductor layer; A second light emitting structure including a first conductive semiconductor layer, an active layer, a second conductive semiconductor layer, and a first electrode on the first conductive semiconductor layer; And a second electrode common to the second conductive semiconductor layer of the first light emitting structure and the second conductive semiconductor layer of the second light emitting structure.

Here, the first light emitting structure is a horizontal light emitting device in which a current is supplied to the first conductive semiconductor layer and the second conductive semiconductor layer in the first light emitting structure from the same direction, and the second light emitting structure is the second light emitting structure. It may be a vertical light emitting device in which a current is supplied to the first conductive semiconductor layer and the second conductive semiconductor layer in the structure from opposite directions.

The first light emitting structure and the second light emitting structure may be vertical light emitting devices in which current is supplied to the first conductive semiconductor layer and the second conductive semiconductor layer from opposite directions.

The first light emitting structure is a horizontal light emitting device in which a current is supplied to the first conductive semiconductor layer and the second conductive semiconductor layer in the first light emitting structure from the same direction, and the first light emitting structure is formed on the insulating substrate. The first electrode of the first light emitting structure may be formed in a via hole type in the substrate.

The first light emitting structure and the second light emitting structure may be connected through a conductive substrate.

The first electrode on the first conductive semiconductor layer of the first light emitting structure and the first electrode on the first conductive semiconductor layer of the second light emitting structure may be energized.

The light emitting device may further include an ohmic layer provided on at least one of the first light emitting structure and the second light emitting structure.

The light emitting device may further include a reflective layer provided on the ohmic layer.

The light emitting device may further include a conductive layer provided on the reflective layer.

The conductive layer may include at least one of nickel, platinum, titanium, tungsten, vanadium, iron, and molybdenum.

In addition, the reflective layer may contact the second conductive semiconductor layer of the second light emitting structure, and the second electrode may be provided on the reflective layer.

Another embodiment includes a first light emitting structure including a first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer, and a second light emitting structure including a first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer. Combining; Forming a first electrode on each of the first conductive semiconductor layer of the first light emitting structure and the first conductive semiconductor layer of the second light emitting structure; And forming a second electrode common to the second conductive semiconductor layer of the first light emitting structure and the second conductive semiconductor layer of the second light emitting structure.

Here, the first light emitting structure is a horizontal light emitting device in which current is supplied to the first conductive semiconductor layer and the second conductive semiconductor layer in the first light emitting structure from the same direction, and the first light emitting structure is formed on the insulating substrate. The forming of the first electrode on the first light emitting structure may include forming a hole in the substrate and injecting an electrode material into the hole.

The combining of the first light emitting structure and the second light emitting structure may be performed through a conductive substrate.

In addition, the first light emitting structure may be etched to expose the first conductive semiconductor layer, and the first electrode may be formed on the exposed first conductive semiconductor layer.

The light emitting device according to the embodiment improves the light efficiency of the light emitting structure.

1 is a view showing a first embodiment of a light emitting device,
2A to 2K are views illustrating a manufacturing process of the light emitting device of FIG.
3 is a view showing a second embodiment of a light emitting device;
4A to 4J are views illustrating a manufacturing process of the light emitting device of FIG.
5 is a view showing a third embodiment of a light emitting device;
6A to 6I are views illustrating a manufacturing process of the light emitting device of FIG. 5;
7 is a cross-sectional view of 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.

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

1 is a view showing a first embodiment of a light emitting device. In FIG. 1, two light emitting devices are coupled through the conductive support substrate 270.

In the first light emitting device of FIG. 1, the first light emitting structure 120 is provided on the substrate 100. The substrate 100 may include a conductive substrate or an insulating substrate, for example, at least one of sapphire (Al ₂ O ₃ ), SiC, Si, GaAs, GaN, ZnO, Si, GaP, InP, Ge, and Ga ₂ 0 ₃ . Can be used. An uneven structure may be formed on the substrate 100, but is not limited thereto.

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 is provided on the substrate 100.

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

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 122 is an N-type semiconductor layer. The first conductive dopant may be an N-type dopant and may include Si, Ge, Sn, Se, or Te, but is not limited thereto.

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. The first conductive semiconductor layer 122 may be formed of any one or more of GaN, InN, AlN, InGaN, AlGaN, InAlGaN, AlInN, AlGaAs, InGaAs, AlInGaAs, GaP, AlGaP, InGaP, AlInGaP, InP. have.

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

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 124 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 is formed of one or more pair structures of InGaN / GaN, InGaN / InGaN, AlGaN / GaN, InAlGaN / GaN, GaAs, / AlGaAs (InGaAs), GaP / AlGaP (InGaP). It may be, but is not limited to such. The well layer may be formed of a material having a lower band gap 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 higher band gap than the band gap of the active layer 124.

The second conductive type semiconductor layer 126 is a second conductive type dopant is doped III-V compound semiconductor, for example _{-5, In x Al y Ga 1 -x-} y 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.

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 120 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.

The second conductive semiconductor layer 126 is etched from a portion of the first conductive semiconductor layer 122. When an insulating substrate is used, such as a sapphire substrate, an electrode cannot be formed under the substrate. A space for forming an electrode (first electrode) is secured.

The ohmic layer 130 and the reflective layer 140 are provided on the second conductivity type semiconductor layer 126. The ohmic layer 230 is provided with a thickness of about 200 angstroms, such as indium tin oxide (ITO), indium zinc oxide (IZO), indium zinc tin oxide (IZTO), indium aluminum zinc oxide (IZAZO), and IGZO (indium). gallium zinc oxide), indium gallium tin oxide (IGTO), aluminum zinc oxide (AZO), antimony tin oxide (ATO), gallium zinc oxide (GZO), IZO Nitride, IZON (IZO Nitride), IGZO (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 At least one of In, Ru, Mg, Zn, Pt, Au, and Hf may be formed, but is not limited thereto.

The reflective layer 240 is formed to a thickness of about 2500 angstroms, such as aluminum (Al), silver (Ag), nickel (Ni), platinum (Pt), rhodium (Rh), or Al, Ag, Pt, or Rh. It may be made of a metal layer comprising an alloy comprising a. Aluminum or silver may effectively reflect light generated from the active layer 224 to improve light extraction efficiency of the light emitting device.

The passivation layer 190 is provided on the exposed side surface of the light emitting structure 120 and the side surfaces of the ohmic layer 130 and the reflective layer 140. The passivation layer 190 may be made of an insulating material, and the insulating material may be made of an oxide or nitride that is non-conductive. As an example, the passivation layer 190 may be formed of a silicon oxide (SiO ₂ ) layer, an oxynitride layer, and an aluminum oxide layer.

In addition, the conductive layer 150 is formed on at least one of nickel (Ni), platinum (Pt), titanium (Ti), tungsten (W), vanadium (V), iron (Fe), and molybdenum (Mo) on the reflective layer 140. It is made of one material and may be made of one layer or a plurality of layers. The conductive layer 250 may surround and support the ohmic layer 230 and the reflective layer 240.

The first light emitting device described above is coupled to the second light emitting device below through the conductive support substrate 270. In this case, a bonding layer 160 is formed between the conductive layer 150 and the conductive support substrate 270, and the bonding layer 260 is made of gold (Au), tin (Sn), indium (In), and aluminum. It may be made of a material selected from the group consisting of (Al), silicon (Si), silver (Ag), nickel (Ni), and copper (Cu) or alloys thereof.

The conductive support substrate 270 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. In addition, 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.

A second light emitting device is provided on the conductive support substrate 270. The conductive layer 250 is provided on the other side of the conductive support substrate 270 (upper in FIG. 1) through the bonding layer 260. In addition, a reflective layer 240 and an ohmic layer 230 are provided on the conductive layer 250, and the conductive layer 250 surrounds the reflective layer 240 and the ohmic layer 230.

In addition, a second light emitting structure 220 is provided on the ohmic layer 230. The second light emitting structure 220 includes a second conductive semiconductor layer 226, an active layer 224, and a first conductive semiconductor layer 222. In addition, irregularities are formed on a surface of the first conductivity-type semiconductor layer 222. The uneven structure also has an effect of increasing the surface area of the first conductivity type semiconductor layer 222, and typically, the number of floors and valleys may be periodic or aperiodic. The composition of the light emitting structure 220, the ohmic layer 230, the reflective layer 240, the conductive layer 250, and the coupling layer 260 in the second light emitting device is the same as that of the same layer in the first light emitting device.

First electrodes 180 and 280 are provided on the first conductivity type semiconductor layers 122 and 222, respectively. The two first electrodes 180 and 280 are separated from each other, but may be energized when a current is supplied to the light emitting device.

A second electrode 285 is provided in the exposed region of the conductive layer 250, and the second electrode 285 becomes a common electrode for the first light emitting device and the second light emitting device. That is, the current supplied through the second electrode 285 supplies current to the second conductive semiconductor layers 126 and 226 together. The first electrodes 180 and 280 and the second electrode 285 are molybdenum, chromium (Cr), nickel (Ni), gold (Au), aluminum (Al), titanium (Ti), platinum (Pt), and vanadium. (V), tungsten (W), lead (Pd), copper (Cu), rhodium (Rh) and iridium (Ir) may be made of any one metal or an alloy of the metals.

In the above-described light emitting device, since the horizontal first light emitting device and the vertical second light emitting device can emit light together, the luminous efficiency can be improved. In addition, the uniformity of the luminance can be expected due to the even light projection in both the horizontal direction and the vertical direction by the action of the reflective layer provided in each light emitting device.

Here, the horizontal light emitting device refers to a light emitting device having the same direction in which current is injected into each conductive semiconductor layer. Referring to FIG. 1, the first conductive semiconductor layer 122 and the second conductive layer of the light emitting structure 120 are referred to. All of the type semiconductor layer 126 is supplied with electric current from an upward direction. The vertical light emitting device refers to a light emitting device having an opposite direction in which current is injected into each conductive semiconductor layer. The vertical light emitting device is upwardly directed to the first conductive semiconductor layer 222 of the light emitting structure 220 with reference to FIG. 1. The current is supplied from the second conductive semiconductor layer 226 and the current is supplied from the downward direction. Definitions of the vertical light emitting device and the horizontal light emitting device are the same in the following embodiments.

2A to 2K are views illustrating a manufacturing process of the light emitting device of FIG. 1. Hereinafter, a manufacturing process of the light emitting device of FIG. 1 will be described with reference to FIGS. 2A to 2K.

First, as shown in FIG. 2A, the light emitting structure 120 is grown on the substrate 100. The substrate 100 may include a conductive substrate or an insulating substrate, for example, at least one of sapphire (Al ₂ O ₃ ), SiC, Si, GaAs, GaN, ZnO, Si, GaP, InP, Ge, and Ga ₂ 0 ₃ . Can 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, a light emitting structure 120 including a first conductive semiconductor layer 122, an active layer 124, and a 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 formed of at least one of Group III-V compound semiconductors such as 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 be grown by vapor deposition such as metal organic chemical vapor deposition (MOCVD), molecular beam epitaxy (MBE), and hydraulic vapor phase epitaxy (HVPE).

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 122 is an N-type semiconductor layer. The first conductive dopant may be an N-type dopant and may include Si, Ge, Sn, Se, or Te, but is not limited thereto.

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. The first conductive semiconductor layer 122 may be formed of any one or more of GaN, InN, AlN, InGaN, AlGaN, InAlGaN, AlInN, AlGaAs, InGaAs, AlInGaAs, GaP, AlGaP, InGaP, AlInGaP, InP. have.

The first conductivity type semiconductor layer 122 may form an N-type GaN layer using a chemical vapor deposition method (CVD), molecular beam epitaxy (MBE), sputtering, or hydroxide vapor phase epitaxy (HVPE). . In addition, the first conductivity type semiconductor layer 122 includes a silane containing n-type impurities such as trimethyl gallium gas (TMGa), ammonia gas (NH ₃ ), nitrogen gas (N ₂ ), and silicon (Si) in the chamber. The gas SiH ₄ may be injected and formed.

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

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 124 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 is formed of one or more pair structures of InGaN / GaN, InGaN / InGaN, AlGaN / GaN, InAlGaN / GaN, GaAs, / AlGaAs (InGaAs), GaP / AlGaP (InGaP). It may be, but is not limited to such. The well layer may be formed of a material having a lower band gap 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 higher band gap than the band gap of the active layer 124.

The second conductive type semiconductor layer 126 is a second conductive type dopant is doped III-V compound semiconductor, for example _{-5, In x Al y Ga 1 -x-} y 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.

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 120 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 shown in FIG. 2B, Mesa is etched from the second conductive semiconductor layer 126 to a portion of the first conductive semiconductor layer 122 by a reactive ion etching (RIE) method. That is, when an insulating substrate is used, such as a sapphire substrate, an electrode may not be formed under the substrate, and thus the mesa may be formed from the second conductive semiconductor layer 126 to a part of the first conductive semiconductor layer 122. By etching, a space for forming an electrode is secured.

As shown in FIG. 2C, the side surface of the light emitting structure 120 is etched to expose the substrate 100. In this case, the etched region in the process illustrated in FIG. 2B is a space for forming an electrode so as not to be damaged. In this case, the ohmic layer 130 and the reflective layer 140 may be formed on the second conductive semiconductor layer 126, and the composition of the ohmic layer 130 and the reflective layer 140 will be described later.

As shown in FIG. 2D, a passivation layer 190 may be deposited on the side surface of the light emitting structure 120 etched in the process of FIG. 2C. In this case, the passivation layer 190 may be deposited at the same height as the reflective layer 140.

Here, the passivation layer 190 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 190 may be formed of a silicon oxide (SiO ₂ ) layer, an oxynitride layer, and an aluminum oxide layer.

A first light emitting device was prepared by the above-described process, and a second light emitting device was prepared below.

First, as shown in FIG. 2E, the light emitting structure 220 is grown on the substrate 200. The light emitting structure 220 includes the first conductive semiconductor layer 222, the active layer 224, and the second conductive semiconductor. Layer 226. Specific composition of the substrate and the light emitting structure 220 is as described in Figure 2a.

As shown in FIG. 2F, the ohmic layer 230 is stacked on the second conductive semiconductor layer 226 to a thickness of about 200 angstroms.

The ohmic layer 230 may include indium tin oxide (ITO), indium zinc oxide (IZO), indium zinc tin oxide (IZTO), indium aluminum zinc oxide (IZAO), indium gallium zinc oxide (IGZO), and indium gallium tin (IGTO). oxide), 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 At least one of Au, Hf, and the like may be formed, and the material is not limited thereto. The ohmic layer 230 may be formed by sputtering or electron beam deposition.

In addition, the reflective layer 240 may be formed on the ohmic layer 230 to a thickness of about 2,500 ounces. The reflective layer 140 may be formed of a metal layer including aluminum (Al), silver (Ag), nickel (Ni), platinum (Pt), rhodium (Rh), or an alloy containing Al, Ag, Pt, or Rh. have. Aluminum or silver may effectively reflect light generated from the active layer 224 to improve light extraction efficiency of the light emitting device.

As illustrated in FIG. 2G, a conductive layer 250 may be formed on the reflective layer 240. The conductive layer 250 is made of at least one of nickel (Ni), platinum (Pt), titanium (Ti), tungsten (W), vanadium (V), iron (Fe), and molybdenum (Mo). It may be composed of one layer or a plurality of layers. The conductive layer 250 may surround and support the ohmic layer 230 and the reflective layer 240.

In addition, a bonding layer 260 may be formed on the conductive layer 250. The conductive layer 250 may function as a bonding layer, or may include gold (Au), tin (Sn), indium (In), The conductive support substrate is formed by forming the bonding layer 260 from a material selected from the group consisting of aluminum (Al), silicon (Si), silver (Ag), nickel (Ni), and copper (Cu) or an alloy thereof. 270 and the conductive layer 250 may be combined.

Then, as shown in Figure 2h, the substrate 200 is separated. The substrate 200 may be removed by a laser lift off (LLO) method using an excimer laser, or by dry and wet etching.

For example, when the laser lift-off method focuses and irradiates excimer laser light having a predetermined wavelength toward the substrate 200, heat energy is applied to the interface between the substrate 200 and the light emitting structure 220. As the interface is concentrated and separated into gallium and nitrogen molecules, separation of the substrate 200 occurs at a moment where the laser light passes.

As shown in FIG. 2I, the light emitting structure 220 is diced by element, and a concave-convex structure is formed on the surface of the first conductive semiconductor layer 222. The uneven structure may be formed by etching the surface of the first conductivity-type semiconductor layer 222, and by adjusting the amount of the etchant (for example, KOH) and the difference in etching speed due to GaN crystallinity, the shape of the unevenness of fine size I can regulate it. The uneven structure also has an effect of increasing the surface area of the first conductivity type semiconductor layer 222, and typically, the number of floors and valleys may be periodic or aperiodic.

As shown in FIG. 2J, the first light emitting device and the second light emitting device manufactured according to the above-described process are combined. At this time, the second conductivity-type semiconductor layer 126 of the first light emitting device and the second conductivity-type semiconductor layer 226 of the second light emitting device are coupled in opposite directions to each other. In order to form a common electrode.

First, the conductive layer 150 is formed on the first light emitting device. The composition of the conductive layer 150 is the same as the conductive layer 250 of the second light emitting device, and may be formed of one layer or a plurality of layers. The conductive layer 150 may surround and support the light emitting structure 120.

In addition, a bonding layer 160 may be formed on the conductive layer 150. The conductive layer 150 may function as a bonding layer, or may include gold (Au), tin (Sn), indium (In), The conductive support substrate is formed by forming the bonding layer 260 from a material selected from the group consisting of aluminum (Al), silicon (Si), silver (Ag), nickel (Ni), and copper (Cu) or an alloy thereof. 270 and the conductive layer 150 may be combined.

In addition, the first light emitting device and the second light emitting device are coupled to each other through the conductive support substrate 270. The coupling layers 160 and 260 may be formed to be coupled to the conductive layers 150 and 250. As shown. In this case, the conductive support substrate 270 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. In addition, 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 270 may be formed using an electrochemical metal deposition method or a bonding method using a eutectic metal.

And an electrode is formed as shown in FIG. 2K.

First, the first electrode 180 is formed on the exposed region of the first conductivity-type semiconductor layer 122 of the first light emitting device. The first electrode 180 may include molybdenum, chromium (Cr), nickel (Ni), gold (Au), aluminum (Al), titanium (Ti), platinum (Pt), vanadium (V), tungsten (W), It is made of any one metal selected from lead (Pd), copper (Cu), rhodium (Rh) and iridium (Ir) or an alloy of the metals. The first electrode 180 may also be formed on a part of the first conductive semiconductor layer 122 using a mask.

In addition, another first electrode 280 is formed on the first conductive semiconductor layer 222 of the second light emitting device. The composition and formation method of the first electrode 280 is the same as the first electrode 180 described above.

The second electrode 285 is formed on the exposed surface of the conductive layer 250 of the second light emitting device. The second electrode 285 may include molybdenum, chromium (Cr), nickel (Ni), gold (Au), aluminum (Al), titanium (Ti), platinum (Pt), vanadium (V), tungsten (W), It is made of any one metal selected from lead (Pd), copper (Cu), rhodium (Rh) and iridium (Ir) or an alloy of the metals. The second electrode 285 may also be formed using a mask.

The second electrode 285 may serve as a common electrode for the first light emitting device and the second light emitting device, and supply current to the second conductive semiconductor layers 126 and 226. In this case, the first light emitting device is formed in a vertical structure, and the second light emitting device is formed in a horizontal structure.

3 is a view showing a second embodiment of a light emitting device. In the light emitting device according to the present embodiment, the structure of the first light emitting device shown below is different from that of the first embodiment.

That is, the light emitting structure 120 is provided on a part of the substrate 100, and the ohmic layer 130 and the reflective layer 140 are provided on a part of the light emitting structure 120. The passivation layer 190 is provided on the entire exposed side surfaces of the light emitting structure 120, the ohmic layer 130, and the reflective layer 140. In addition, a hole is provided in the substrate 100, and an electrode material is filled in the hole to provide the first electrode 180.

In the light emitting device according to the present embodiment, two vertical light emitting devices are combined, and the luminance of the horizontal direction and the vertical direction can be expected by the action of the reflective layers 140 and 240 provided in the respective light emitting devices.

4A to 4J are views illustrating a manufacturing process of the light emitting device of FIG. 3. Hereinafter, a manufacturing process of the light emitting device of FIG. 3 will be described with reference to FIGS. 4A to 4J.

First, a first light emitting device is prepared by the process illustrated in FIGS. 4A to 4C. As shown in FIG. 4A, the light emitting structure 120 is grown on the substrate 100. Composition and growth methods of the substrate 100 and the light emitting structure 120 are the same as described with reference to FIG. 2A.

The ohmic layer 130 and the reflective layer 140 are formed on the second conductive semiconductor layer 126. The composition and formation method of the ohmic layer 130 and the reflective layer 140 are as described with reference to FIG. 2F and the like. same. In addition, the mask may be formed on a portion of the light emitting structure 120 using a mask of the ohmic layer 130 and the reflective layer 140.

Subsequently, a passivation layer 190 may be deposited on side surfaces of the light emitting structure 120, the ohmic layer 130, and the reflective layer 140 as illustrated in 4c. In this case, the passivation layer 190 may be deposited at the same height as the reflective layer 140, and the current may pass through the light emitting structure 120 only when the passivation layer 190 is formed so as not to cover the reflective layer 140. In this case, after dicing the light emitting structure 120 in element units, the passivation layer 190 may be formed in each element unit. Here, the passivation layer 190 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 190 may be formed of a silicon oxide (SiO ₂ ) layer, an oxynitride layer, and an aluminum oxide layer.

A first light emitting device was prepared by the above-described process, and a second light emitting device was prepared below.

First, as shown in FIG. 4D, the light emitting structure 220 is grown on the substrate 200. The light emitting structure 220 includes the first conductive semiconductor layer 222, the active layer 224, and the second conductive semiconductor. Layer 226. Specific composition of the substrate and the light emitting structure 220 is as described above.

As shown in FIG. 4E, an ohmic layer 230 and a reflective layer 240 are formed on a portion of the light emitting structure 220, and as shown in FIG. 4F, the light emitting structure 220 and the ohmic layer ( The conductive layer 250 and the bonding layer 260 may be formed on the 230 and the reflective layer 240. The bonding layer 260 may be formed immediately before the bonding process with the conductive support substrate 270, and the embodiments described above and below will be the same.

 The composition and formation process of the ohmic layer 230, the reflective layer 240, the conductive layer 250, and the bonding layer 260 are as described above.

Then, the substrate 200 is separated as shown in FIG. 4G. The substrate 200 may be removed by a laser lift off (LLO) method using an excimer laser, or by dry and wet etching.

As shown in FIG. 4H, the light emitting structure 220 is diced by element, and an uneven structure is formed on the surface of the first conductive semiconductor layer 222.

As shown in FIG. 4I, the first light emitting device and the second light emitting device manufactured according to the above-described process are combined. At this time, the second conductivity-type semiconductor layer 126 of the first light emitting device and the second conductivity-type semiconductor layer 226 of the second light emitting device are coupled in opposite directions to each other. In order to form a common electrode.

The ohmic layer 130 and the coupling layer 140 of the first light emitting device may be formed to have the same width as the ohmic layer 230 and the coupling layer 240 of the second light emitting device. Examples and embodiments to be described later are also the same.

In this case, the conductive layer 150 is formed on the first light emitting device. The composition of the conductive layer 150 is the same as the conductive layer 250 of the second light emitting device, and may be formed of one layer or a plurality of layers. The conductive layer 150 may surround and support the light emitting structure 120.

In addition, a bonding layer 160 may be formed on the conductive layer 150. The conductive layer 150 may function as a bonding layer, or may include gold (Au), tin (Sn), indium (In), The conductive support substrate is formed by forming the bonding layer 260 from a material selected from the group consisting of aluminum (Al), silicon (Si), silver (Ag), nickel (Ni), and copper (Cu) or an alloy thereof. 270 and the conductive layer 150 may be combined.

In addition, the first light emitting device and the second light emitting device are coupled to each other through the conductive support substrate 270. The coupling layers 160 and 260 may be formed to be coupled to the conductive layers 150 and 250. As shown. In this case, the conductive support substrate 270 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. In addition, 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 270 may be formed using an electrochemical metal deposition method or a bonding method using a eutectic metal.

And an electrode is formed as shown in FIG. 4J.

First, a hole may be formed in the substrate 100 of the first light emitting device, and a material may be injected to form the first electrode 180. The first electrode 180 may include molybdenum, chromium (Cr), nickel (Ni), gold (Au), aluminum (Al), titanium (Ti), platinum (Pt), vanadium (V), tungsten (W), It is made of any one metal selected from lead (Pd), copper (Cu), rhodium (Rh) and iridium (Ir) or an alloy of the metals. In order to form the holes described above, the substrate 100 may be etched with a laser or drilled with a drill. The injection of the first electrode 180 may be performed by a plating method or the like.

In addition, another first electrode 280 is formed on the first conductive semiconductor layer 222 of the second light emitting device. The composition and formation method of the first electrode 280 is the same as the first electrode 180 described above.

The second electrode 285 is formed on the exposed surface of the conductive layer 250 of the second light emitting device. The second electrode 285 may be made of the same material as the first electrodes 9180 and 280. The second electrode 285 may be formed using a mask.

The second electrode 285 may serve as a common electrode for the first light emitting device and the second light emitting device, and supply current to the second conductive semiconductor layers 126 and 226. In this case, the first light emitting device is formed in a vertical structure, and the second light emitting device is also formed in a vertical structure.

5 is a view showing a third embodiment of the light emitting device.

The light emitting device according to the present embodiment is the same as the second embodiment, except that the passivation layer on the side of the first light emitting device is omitted. That is, the ohmic layer 130 and the reflective layer 140 are provided on a portion of the first light emitting structure 120, and the conductive layer 150 surrounds the ohmic layer 130 and the reflective layer 140. A passivation layer (not shown) may be provided on side surfaces of the entire light emitting device including the first light emitting device and the second light emitting device.

6A to 6I are views illustrating a manufacturing process of the light emitting device of FIG. 5. Hereinafter, a manufacturing process of the light emitting device of FIG. 5 will be described with reference to FIGS. 6A to 6I.

First, a first light emitting device is prepared by the process illustrated in FIGS. 6A to 6B. As shown in FIG. 4A, the light emitting structure 120 is grown on the substrate 100. Composition and growth methods of the substrate 100 and the light emitting structure 120 are the same as described with reference to FIG. 2A.

The ohmic layer 130 and the reflective layer 140 are formed on the second conductive semiconductor layer 126. The composition and formation method of the ohmic layer 130 and the reflective layer 140 are as described with reference to FIG. 2F and the like. same. In addition, the mask may be formed on a portion of the light emitting structure 120 using a mask of the ohmic layer 130 and the reflective layer 140.

A first light emitting device was prepared by the above-described process, and a second light emitting device was prepared below.

A process of preparing the second light emitting device is illustrated in FIGS. 6C to 6G, and is the same as the process illustrated in FIGS. 4D to 4H.

Then, as shown in FIG. 6h, the first light emitting device and the second light emitting device manufactured according to the above-described process are combined. At this time, the second conductivity-type semiconductor layer 126 of the first light emitting device and the second conductivity-type semiconductor layer 226 of the second light emitting device are coupled in opposite directions to each other. In order to form a common electrode.

In this case, the conductive layer 150 is formed on the first light emitting device. The composition of the conductive layer 150 is the same as the conductive layer 250 of the second light emitting device, and may be formed of one layer or a plurality of layers. The conductive layer 150 may surround and support the light emitting structure 120.

In addition, the first light emitting device and the second light emitting device may be coupled to each other on the conductive support substrate 270 through the coupling layers 160 and 260, and the second electrode may be a common electrode with the first electrodes 180 and 280. 285) is the same.

The passivation layer (not shown) may be formed on the side of the entire light emitting device according to the embodiment to protect the light emitting structures 120 and 220.

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

As illustrated, the light emitting device package according to the embodiments includes a package body 320, a first electrode layer 311 and a second electrode layer 312 installed on the package body 320, and the package body 320. The light emitting device 300 includes a light emitting device 300 according to the embodiment and is electrically connected to the first electrode layer 311 and the second electrode layer 312, and a filler 340 surrounding the light emitting device 300.

The package body 320 may include a silicon material, a synthetic resin material, or a metal material. An inclined surface may be formed around the light emitting device 300 to increase light extraction efficiency.

The first electrode layer 311 and the second electrode layer 312 are electrically separated from each other, and provide power to the light emitting device 300. In addition, the first electrode layer 311 and the second electrode layer 312 can increase the light efficiency by reflecting the light generated from the light emitting device 300, the outside of the heat generated from the light emitting device 300 May also act as a drain.

The light emitting device 300 may be installed on the package body 320 or on the first electrode layer 311 or the second electrode layer 312.

The light emitting device 300 may be electrically connected to the first electrode layer 311 and the second electrode layer 312 by any one of a wire method, a flip chip method, or a die bonding method.

The filler 340 may surround and protect the light emitting device 300. In addition, the filler 340 may include a phosphor to change the wavelength of light emitted from the light emitting device 300.

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. .

In addition, the above description has been made with reference to the embodiment, which is merely an example, and is not intended to limit the present invention. Those skilled in the art to which the present invention pertains will be illustrated as above 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 embodiment can be modified. And differences relating to such modifications and applications will have to be construed as being included in the scope of the invention defined in the appended claims.

100, 200: substrate 120, 220: light emitting structure
122, 222: first conductive semiconductor layer 124, 224: active layer
126, 226: second conductive semiconductor layer 130, 230: ohmic layer
140, 240: reflective layer 150, 250: conductive layer
160, 260: bonding layer 180, 280: first electrode
190: passivation layer 270: conductive support substrate
285: second electrode 300: light emitting element
311: first electrode layer 312: second electrode layer
320: package body 340: filler

Claims (15)

A first light emitting structure including a first conductive semiconductor layer, an active layer, a second conductive semiconductor layer, and a first electrode on the first conductive semiconductor layer;
A second light emitting structure including a first conductive semiconductor layer, an active layer, a second conductive semiconductor layer, and a first electrode on the first conductive semiconductor layer; And
And a second electrode common to the second conductive semiconductor layer of the first light emitting structure and the second conductive semiconductor layer of the second light emitting structure. The method of claim 1,
The first light emitting structure is a horizontal light emitting device in which a current is supplied to the first conductive semiconductor layer and the second conductive semiconductor layer in the first light emitting structure from the same direction, and the second light emitting structure is formed in the second light emitting structure. A light emitting device which is a vertical light emitting device in which a current is supplied to the first conductive semiconductor layer and the second conductive semiconductor layer from opposite directions. The method of claim 1,
And the first light emitting structure and the second light emitting structure are vertical light emitting devices in which a current is supplied to the first conductive semiconductor layer and the second conductive semiconductor layer from opposite directions. The first light emitting structure is a horizontal light emitting device in which current is supplied to a first conductive semiconductor layer and a second conductive semiconductor layer in the first light emitting structure from the same direction, and the first light emitting structure is provided on an insulating substrate. And a first electrode of the first light emitting structure having a via hole type in the substrate. The method of claim 1,
The light emitting device is connected to the first light emitting structure and the second light emitting structure through a conductive substrate. The method of claim 1,
And a first electrode on the first conductive semiconductor layer of the first light emitting structure and a first electrode on the first conductive semiconductor layer of the second light emitting structure are energized. The method of claim 1,
The light emitting device further comprises an ohmic layer provided on at least one of the first light emitting structure and the second light emitting structure. The method of claim 7, wherein
Light emitting device further comprises a reflective layer provided on the ohmic layer. The method of claim 8,
Light emitting device further comprises a conductive layer provided on the reflective layer. The method of claim 9,
The conductive layer includes at least one of nickel, platinum, titanium, tungsten, vanadium, iron and molybdenum. The method of claim 9,
The reflective layer is in contact with the second conductive semiconductor layer of the second light emitting structure, the second electrode is provided on the reflective layer. Combining the first light emitting structure including the first conductive semiconductor layer, the active layer, and the second conductive semiconductor layer, and the second light emitting structure including the first conductive semiconductor layer, the active layer, and the second conductive semiconductor layer. ;
Forming a first electrode on each of the first conductive semiconductor layer of the first light emitting structure and the first conductive semiconductor layer of the second light emitting structure; And
And forming a second electrode common to the second conductive semiconductor layer of the first light emitting structure and the second conductive semiconductor layer of the second light emitting structure. The method of claim 12,
The first light emitting structure is a horizontal light emitting device in which current is supplied to a first conductive semiconductor layer and a second conductive semiconductor layer in the first light emitting structure from the same direction, and the first light emitting structure is provided on an insulating substrate. And forming a first electrode in the first light emitting structure to form a hole in the substrate and inject an electrode material into the hole. The method of claim 12,
The combining of the first light emitting structure and the second light emitting structure is a method of manufacturing a light emitting device to be coupled through a conductive substrate. The method of claim 12,
And etching the first light emitting structure to expose the first conductive semiconductor layer and to form the first electrode on the exposed first conductive semiconductor layer.

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