KR20120135722A - Light emitting device - Google Patents

Abstract

The light emitting device according to the embodiment includes a substrate, a first semiconductor layer disposed on the substrate, the first semiconductor layer, and an active layer between the second semiconductor layer, the third semiconductor layer, and the second and third semiconductor layers. A light emitting structure comprising a, a fourth semiconductor layer disposed on the first semiconductor layer, and separated from the light emitting structure, a passivation disposed between the light emitting structure and the fourth semiconductor layer, on the first and second semiconductor layers It may include a first electrode disposed in the and the second electrode disposed on the passivation and the third, fourth semiconductor layer.

Description

[0001]

The embodiment relates to a light emitting device having a resistance to ESD and achieving a light emitting area.

As a typical example of a light emitting device, a light emitting diode (LED) is a device for converting an electric signal into an infrared ray, a visible ray, or a light using the characteristics of a compound semiconductor, and is used for various devices such as household appliances, remote controllers, Automation equipment, and the like, and the use area of LEDs is gradually widening.

In general, miniaturized LEDs are made of a surface mounting device for mounting directly on a PCB (Printed Circuit Board) substrate, and an LED lamp used as a display device is also being developed as a surface mounting device type . Such a surface mount device can replace a conventional simple lighting lamp, which is used for a lighting indicator for various colors, a character indicator, an image indicator, and the like.

As the use area of the LED is widened as described above, it is important to increase the luminance of the LED as the brightness required for a lamp used in daily life and a lamp for a structural signal is increased.

Meanwhile, in order to apply the light emitting device to a TV, an MNT, or a general lighting device, a certain level of electrostatic discharge (ESD) resistance is required.

Electrostatic Discharge (ESD) is an electrostatic discharge, typically thousands of volts or more, that occurs when an electronic device comes in contact with a charged object and damages the light emitting device, as well as the power supply that supplies the light emitting device, and various other electronic devices. Can be added.

In general, when the light emitting device is applied to a device such as a backlight, a zener diode is added to one side of a package of the light emitting device, and the light emitting device is resistant to ESD using the zener diode.

However, when a Zener diode is added to the package to make the nitride light emitting device resistant to ESD, the Zener diode is adjacent to the light emitting device in the package and thus affects the brightness of the light emitting device. It acts as a absorbing part of the light emitted from the light emitting device to reduce the brightness of the light emitting device. In addition, since the Zener diode is housed in the package, the aspect of increasing the manufacturing cost of the entire package cannot be overlooked.

The embodiment provides a light emitting device having a resistance to ESD and achieving a light emitting area.

The light emitting device according to the embodiment includes a substrate, a first semiconductor layer disposed on the substrate, the first semiconductor layer, and an active layer between the second semiconductor layer, the third semiconductor layer, and the second and third semiconductor layers. A light emitting structure comprising a, a fourth semiconductor layer disposed on the first semiconductor layer, and separated from the light emitting structure, a passivation disposed between the light emitting structure and the fourth semiconductor layer, on the first and second semiconductor layers It may include a first electrode disposed in the and the second electrode disposed on the passivation and the third, fourth semiconductor layer.

The light emitting device according to the embodiment includes a substrate, a first semiconductor layer disposed on the substrate, the first semiconductor layer, and an active layer between the second semiconductor layer, the third semiconductor layer, and the second and third semiconductor layers. A light emitting structure comprising: a fourth semiconductor layer disposed on the first semiconductor layer and separated from the light emitting structure and positioned inside the light emitting structure; a passivation disposed between the light emitting structure and the fourth semiconductor layer; The semiconductor device may include a first electrode disposed on the first and second semiconductor layers, and a second electrode disposed on the passivation and the third and fourth semiconductor layers.

The light emitting device according to the embodiment has resistance to ESD, thereby preventing damage caused by ESD and improving reliability.

In addition, the light emitting device package in which the light emitting device is mounted may not require a separate ESD device, thereby improving light emission efficiency of the light emitting device package.

1 is a cross-sectional view showing a light emitting device according to an embodiment.
FIG. 2 is a diagram illustrating an operation when a forward current is applied to the light emitting device shown in FIG. 1.
3 is an operation diagram illustrating an operation when a reverse current is applied to the light emitting device shown in FIG. 1.
4 is a cross-sectional view illustrating a light emitting device according to an embodiment.
FIG. 5 is an operation diagram illustrating an operation when a forward current is applied to the light emitting device shown in FIG. 4.
6 is an operation diagram illustrating an operation when a reverse current is applied to the light emitting device shown in FIG. 4.
7 is a perspective view showing a light emitting device package including a light emitting device according to the embodiment.
8 is a cross-sectional view illustrating a cross section of a light emitting device package including a light emitting device according to the embodiment.
9 is a perspective view illustrating a lighting system including a light emitting device according to the embodiment.
10 is a cross-sectional view taken along the line AA ′ of the lighting system of FIG. 9.
11 is an exploded perspective view of a liquid crystal display including the light emitting device according to the embodiment.
12 is an exploded perspective view of a liquid crystal display including the light emitting device according to the embodiment.

Prior to the description of the embodiments, the substrate, each layer region, pad, or pattern of each layer (film), region, pattern, or structure referred to herein is "on", "below ( "on" and "under" include all that is formed "directly" or "indirectly" through other layers. 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. Thus, the size of each component does not fully reflect its actual size.

In addition, the angle and direction mentioned in the process of describing the structure of the light emitting device herein are based on those described in the drawings. In the description of the structure of the light emitting device in the specification, reference points and positional relationship with respect to angles are not explicitly referred to, refer to the related drawings.

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

Referring to FIG. 1, the light emitting device 100 may include a substrate 110, a light emitting structure 115, and first and second electrodes 180 and 190.

Here, the light emitting device 100 includes a LED using a plurality of compound semiconductor layers, for example, a compound semiconductor layer of Group 3-5 elements, and the LED is a colored LED or UV that emits light such as blue, green, or red. It may be an LED. The emission light of the LED may be implemented using various semiconductors within the technical scope of the embodiment.

The light emitting structure 115 may include a second semiconductor layer 130, a third semiconductor layer 150, and an active layer 140 formed between the second semiconductor layer 130 and the third semiconductor layer 150. .

In addition, the light emitting structure 115 may be formed on the substrate 110.

The substrate 110 may be formed using a transparent material including sapphire (Al ₂ O ₃ ), and in addition to sapphire, the substrate 110 may be formed of zinc oxide (ZnO), gallium nitride (GaN), or the like. ), Silicon carbide (SiC), silicon and aluminum nitride (AlN).

Hereinafter, in the embodiment, an insulating substrate such as sapphire (Al ₂ O ₃ ) will be described as an example.

An uneven pattern or light extraction structure may be formed on the substrate 110, and the shape may be formed in a lens shape, a pillar shape, a horn shape, and the like, but is not limited thereto.

The thickness of the substrate 110 may be formed in the range of 100 ~ 400㎛, it is not limited thereto.

The buffer layer 111 may be formed on the substrate 110, and the buffer layer 111 may mitigate lattice mismatch between the substrate 110 and the first semiconductor layer 120.

The buffer layer 111 may be formed in a low temperature atmosphere, and may be selected from materials such as GaN, InN, AlN, AlInN, InGaN, AlGaN, and InAlGaN.

The first semiconductor layer 120 may be formed on the buffer layer 111, and the first semiconductor layer 120 may include at least one of p-type and n-type semiconductor layers.

That is, the first semiconductor layer 120 is n-type when the semiconductor layer, In _x Al _y Ga _{1 -x- y} N (0≤x≤1, 0≤y≤1, 0≤x + y≤1) A semiconductor material having a compositional formula, for example, GaN, AlN, AlGaN, InGaN, InN, InAlGaN, AlInN, or the like, may be selected, and n-type dopants such as Si, Ge, Sn, and the like may be doped.

In addition, the first semiconductor layer 120 is p-type when the semiconductor layer, In _x Al _y Ga _{1 -x- y} N (0≤x≤1, 0≤y≤1, 0≤x + y≤1) A semiconductor material having a compositional formula may be selected from, for example, GaN, AlN, AlGaN, InGaN, InN, InAlGaN, AlInN, and the like, and p-type dopants such as Mg, Zn, Ca, Sr, and Ba may be doped.

In an embodiment, the first semiconductor layer 120 is described as having the same characteristics as the third semiconductor layer 150, and the thickness of the first semiconductor layer 120 may be 10 nm to 1 mm, but not limited thereto. Do not.

In an embodiment, the first semiconductor layer 120 is described as being formed of a p-type semiconductor layer, but may include an n-type semiconductor layer, but is not limited thereto.

The second semiconductor layer 130 may be formed on the first semiconductor layer 120.

At this time, the second semiconductor layer 130 is an n-type semiconductor layer, the composition formula of In _x Al _y Ga _{1 -x- y} N (0≤x≤1, 0≤y≤1, 0≤x + y≤1) And a semiconductor material having, for example, GaN, AlN, AlGaN, InGaN, InN, InAlGaN, AlInN, and the like, and n-type dopants such as Si, Ge, Sn, and the like may be doped.

The active layer 140 may be formed on the second semiconductor layer 130. The active layer 140 is an area where electrons and holes are recombined. The active layer 140 transitions to a low energy level as the electrons and holes recombine, and may generate light having a corresponding wavelength.

The active layer 140 is, for example, including a semiconductor material having a compositional formula of _{In x Al y Ga 1 -x- y} N (0≤x≤1, 0≤y≤1, 0≤x + y≤1) It may be formed, and may be formed of a single quantum well structure or a multi quantum well structure (MQW). In addition, a quantum wire structure or a quantum dot structure may be included.

A clad layer (not shown) may be formed on or under the active layer 140, and the clad layer may be formed of a GaN-based semiconductor, or may be formed of a material having a band gap different from that of the active layer 140.

The third semiconductor layer 150 may inject a carrier into the active layer 140. For example, the third semiconductor layer 150 may be implemented as a p-type semiconductor layer, and the p-type semiconductor layer may have In _x Al _y Ga _{1 -x- y} N (0 ≦ x ≦ 1, 0 ≦ _y ≦ 1). , 0 ≦ x + y ≦ 1), for example, GaN, AlN, AlGaN, InGaN, InN, InAlGaN, AlInN, and the like, and may be selected from p, such as Mg, Zn, Ca, Sr, and Ba. Type dopants may be doped.

In addition, the dopant doping concentrations in the second and third semiconductor layers 130 and 150 may be uniformly or non-uniformly formed, and the structure of the plurality of semiconductor layers may be variously formed, without being limited thereto.

In this case, the third semiconductor layer 150 may have the same dopant doping concentration as the first semiconductor layer 120, and may be formed to be the same as or larger than the thickness of the first semiconductor layer 120. Do not leave.

In addition, a fourth semiconductor layer 160 spaced apart from the side surface of the light emitting structure 115 may be formed on the first semiconductor layer 120.

The fourth semiconductor layer 160 is the same n-type semiconductor layer as the second semiconductor layer 120, and may be formed to be the same as or smaller than the thickness of the second semiconductor layer 120.

That is, the fourth semiconductor layer 160 does not emit light differently from the light emitting structure 115, and the zener for protecting the light emitting structure 115 or the light emitting device 100 by ESD together with the first semiconductor layer 160. It may have diode characteristics.

Detailed description of the first and fourth semiconductor layers 120 and 160 will be described later.

The first semiconductor layer 120, the second and third semiconductor layers 130 and 150, the active layer 130, and the fourth semiconductor layer 160 may be, for example, metal organic chemical vapor deposition (MOCVD). Deposition), Chemical Vapor Deposition (CVD), Plasma-Enhanced Chemical Vapor Deposition (PECVD), Molecular Beam Epitaxy (MBE), Hydride Vapor Phase Epitaxy (HVPE) ), Sputtering and the like can be formed, but is not limited thereto.

The passivation 170 may be formed between the light emitting structure 115 and the fourth semiconductor layer 160.

The passivation 170 may be disposed on side surfaces of the second and third semiconductor layers 130 and 150 and the active layer 140, a portion of an upper surface of the first semiconductor layer 120, and a side surface of the fourth semiconductor layer 160. There is no limitation to this.

The passivation 170 may insulate the second and third semiconductor layers 130 and 150, the active layer 140, and the fourth semiconductor layer 160.

The first electrode 180 may be formed on an upper portion of the first semiconductor layer 120 and a side portion of the second semiconductor layer 130, and a second electrode (on the third and fourth semiconductor layers 150 and 160). 190 may be formed.

Here, the first and second electrodes 180 and 190 may supply power to the second and third semiconductor layers 130 and 150.

The first and second electrodes 180 and 190 are in ohmic contact with the second and third semiconductor layers 130 and 150 to smoothly supply power to the light emitting structure 115. The first and second electrodes 180 and 190 may selectively use a translucent conductive layer and a metal. For example, indium tin oxide (ITO), indium zinc oxide (IZO), indium zinc tin oxide (IZTO), and IAZO may be used. (indium aluminum zinc oxide), IGZO (indium gallium zinc oxide), IGTO (indium gallium tin oxide), AZO (aluminum zinc oxide), ATO (antimony tin oxide), GZO (gallium zinc oxide), IrOx, RuOx, RuOx / ITO, nickel (Ni), platinum (Pt), ruthenium (Ru), iridium (Ir), rhodium (Rh), tantalum (Ta), molybdenum (Mo), titanium (Ti), silver (Ag), tungsten (W ), Copper (Cu), chromium (Cr), palladium (Pd), vanadium (V), cobalt (Co), niobium (Nb), zirconium (Zr), Ni / IrOx / Au, or Ni / IrOx / Au / ITO and carbon nanotubes may be formed in a single layer or multiple layers using at least one of, but are not limited thereto.

Here, the first electrode 180 may be formed at a portion where the step is formed by removing the upper region of the second semiconductor layer 130, and may contact the first semiconductor layer 120.

That is, the first electrode 180 may be formed on the second semiconductor layer 130. The position at which the first electrode 180 is formed is not limited, and a plurality of electrodes may be formed in consideration of the size of the light emitting device 100, but some regions of the third semiconductor layer 150 and the active layer 140 are removed. A portion of the second semiconductor layer 130 may be exposed, and the first electrode 180 may be formed on the exposed upper surface of the second semiconductor layer 130.

The method of removing the upper region of the second semiconductor layer 130 is not limited, but a wet etching method or a dry etching method may be used.

2 is an operation diagram showing an operation when a forward current is applied to the light emitting device shown in Figure 1, Figure 3 is an operation diagram showing an operation when a reverse current is applied to the light emitting device shown in FIG.

Referring to FIG. 2, the light emitting device 100 may be supplied with the positive voltage v1 to the second electrode 190 and the negative voltage v2 to the first electrode 180.

In this case, the positive voltage v1 is supplied to the third semiconductor layer 150 and the fourth semiconductor layer 160 of the light emitting structure 115, and is supplied to the second semiconductor layer 130 and the first semiconductor layer 120. The negative voltage v2 is supplied.

Here, the third semiconductor layer 150 provides holes to the active layer 140 by the positive voltage v1, and the second semiconductor layer 130 supplies electrons to the active layer 140 by the negative voltage v2. Can be provided as

Therefore, the active layer 140 may generate light by recombining holes and electrons as described above.

In addition, since the fourth semiconductor layer 160 is an n-type semiconductor layer different from the third semiconductor layer 150, holes cannot be provided when the positive voltage v1 is supplied, and the first semiconductor layer 120 is provided. Since the p-type semiconductor layer is different from the second semiconductor layer 130, the electrons cannot be provided when the negative voltage v2 is supplied, and the resistances of the first and fourth semiconductor layers 120 and 160 are the second and the third semiconductor layers. The semiconductor layer 130 may be formed larger than the resistance of the semiconductor layers 130 and 150.

Therefore, the first and fourth semiconductor layers 120 and 160 may not influence the light emission from the light emitting structure 115, and the positive voltage v1 and the negative voltage v2 may not be supplied.

Referring to FIG. 3, in the light emitting device 100, a negative voltage v2 may be supplied to the second electrode 190, and a positive voltage v1 may be supplied to the first electrode 180.

That is, FIG. 3 illustrates that the reverse voltage ESD is generated in the light emitting device 100.

In this case, the negative voltage v2 is supplied to the third semiconductor layer 150 and the fourth semiconductor layer 160 of the light emitting structure 115, and is supplied to the second semiconductor layer 130 and the first semiconductor layer 120. The positive voltage v1 is supplied.

Herein, when the positive voltage v1 and the negative voltage v2 are supplied to each of the second and third semiconductor layers 130 and 150, the resistance is increased to prevent the current path from being formed.

In this case, the first semiconductor layer 120 may form holes by the positive voltage v1 supplied from the first electrode 180, and the fourth semiconductor layer 160 is supplied from the second electrode 190. Electrons can be formed by the negative electrode voltage v2.

In other words, since a current path is formed between the first and fourth semiconductor layers 120 and 160, damage to the light emitting structure 115 may be prevented by the reverse voltage ESD.

4 is a cross-sectional view illustrating a light emitting device according to an embodiment.

FIG. 4 omits or briefly describes a configuration that overlaps with FIG. 1.

Referring to FIG. 4, the light emitting device 200 includes a light emitting structure including an active layer 240 between a second semiconductor layer 230, a third semiconductor layer 250, and second and third semiconductor layers 230 and 250. 215 and the light emitting structure 215 may include a fourth semiconductor layer 260 disposed to surround the circumference.

The substrate 210, the buffer layer 211, and the first semiconductor layer 220 illustrated in FIG. 4 will not be described as described with reference to FIG. 1.

After at least one region of the inside of the light emitting structure 215 is removed to expose at least one region of the first semiconductor layer 220, a fourth semiconductor layer 260 is formed on the notched first semiconductor layer 220. Can be. Meanwhile, a method of removing the light emitting structure 215 may use a predetermined etching process as described above.

The passivation 270 may be formed on the periphery of the fourth semiconductor layer 260 and the inner surface of the light emitting structure 215, and the passivation 270 may include the second semiconductor layer 230, the active layer 240, and the third semiconductor layer 260. The semiconductor layer 250 and the fourth semiconductor layer 260 may be electrically insulated from each other.

Here, the first semiconductor layer 220 is a p-type semiconductor layer, the second semiconductor layer 230 is an n-type semiconductor layer, the third semiconductor layer 250 is a p-type semiconductor layer and the fourth semiconductor layer 260 is n It may be a type semiconductor layer, but is not limited thereto.

In this case, a second electrode 290 disposed on the passivation 270 and electrically connected to the third and fourth semiconductor layers 250 and 260 may be formed, and the first and second semiconductor layers 220 and 230 may be formed. The first electrode 280 may be formed to be electrically connected to the first electrode 280.

The light emitting device 200 illustrated in FIG. 4 may operate in the same manner as the light emitting device 100 illustrated in FIG. 1.

5 is an operation diagram showing an operation when a forward current is applied to the light emitting device shown in Figure 4, Figure 6 is an operation diagram showing an operation when a reverse current is applied to the light emitting device shown in FIG.

Referring to FIG. 5, the light emitting device 200 may be supplied with the positive voltage v1 to the second electrode 290 and the negative voltage v2 to the first electrode 280.

In this case, the positive voltage v1 is supplied to the third semiconductor layer 250 and the fourth semiconductor layer 260 of the light emitting structure 215, and is supplied to the second semiconductor layer 230 and the first semiconductor layer 220. The negative voltage v2 is supplied.

Here, the third semiconductor layer 250 provides holes to the active layer 240 by the positive voltage v1, and the second semiconductor layer 230 supplies electrons to the active layer 240 by the negative voltage v2. Can be provided as

Therefore, the active layer 240 may generate light by recombining holes and electrons as described above.

Meanwhile, the first and fourth semiconductor layers 220 and 260 may not affect light emission from the light emitting structure 215, and the positive voltage v1 and the negative voltage v2 may not be supplied.

Referring to FIG. 6, in the light emitting device 200, the negative voltage v2 may be supplied to the second electrode 290, and the positive voltage v1 may be supplied to the first electrode 280.

That is, FIG. 6 illustrates that the reverse voltage ESD is generated in the light emitting device 200.

In this case, the negative voltage v2 is supplied to the third semiconductor layer 250 and the fourth semiconductor layer 260 of the light emitting structure 215, and is supplied to the second semiconductor layer 230 and the first semiconductor layer 220. The positive voltage v1 is supplied.

Herein, when the positive voltage v1 and the negative voltage v2 are supplied to each of the second and third semiconductor layers 230 and 250, the resistance is increased to prevent the current path from being formed.

In this case, the first semiconductor layer 220 may form holes by the positive voltage v1 supplied from the first electrode 280, and the fourth semiconductor layer 260 may be supplied from the second electrode 290. Electrons can be formed by the negative electrode voltage v2.

In other words, since a current path is formed between the first and fourth semiconductor layers 220 and 260, damage to the light emitting structure 215 may be prevented by the reverse voltage ESD.

7 is a perspective view illustrating a light emitting device package including a light emitting device according to an embodiment, and FIG. 8 is a cross-sectional view illustrating a cross section of a light emitting device package including a light emitting device according to an embodiment.

Referring to FIGS. 7 and 8, the light emitting device package 300 may be electrically connected to a body 310 having a cavity formed therein, and first and second electrodes 340 and 350 mounted on the body 310. The light emitting device 320 and the encapsulant 330 formed in the cavity may be included, and the encapsulant 330 may include the phosphor 340.

The body 310 may be made of a resin material such as polyphthalamide (PPA), silicon (Si), aluminum (Al), aluminum nitride (AlN), photo sensitive glass (PSG), polyamide 9T ), new geo-isotactic polystyrene (SPS), metal materials, sapphire (Al ₂ O _3), beryllium oxide (BeO), is a printed circuit board (PCB, printed circuit board), it may be formed of at least one of ceramic. The body 310 may be formed by injection molding, etching, or the like, but is not limited thereto.

The inner surface of the body 310 may be formed with an inclined surface. The reflection angle of the light emitted from the light emitting device 320 can be changed according to the angle of the inclined surface, and thus the directivity angle of the light emitted to the outside can be adjusted.

The shape of the cavity formed in the body 310 as viewed from above may be circular, rectangular, polygonal, elliptical, or the like, and in particular, may have a curved shape, but is not limited thereto.

The encapsulant 330 may be filled in the cavity and may include a phosphor (not shown). The encapsulant 330 may be formed of transparent silicone, epoxy, and other resin materials, and may be formed by filling in a cavity and then ultraviolet or thermal curing.

The phosphor (not shown) may be selected according to the wavelength of the light emitted from the light emitting device 320 to allow the light emitting device package 300 to realize white light.

The fluorescent material (not shown) included in the encapsulant 330 may be a blue light emitting phosphor, a blue light emitting fluorescent material, a green light emitting fluorescent material, a yellow green light emitting fluorescent material, a yellow light emitting fluorescent material, Fluorescent material, orange light-emitting fluorescent material, and red light-emitting fluorescent material may be applied.

That is, the phosphor (not shown) may be excited by the light having the first light emitted from the light emitting device 320 to generate the second light. For example, when the light emitting element 320 is a blue light emitting diode and the phosphor (not shown) is a yellow phosphor, the yellow phosphor may be excited by blue light to emit yellow light, and blue light emitted from the blue light emitting diode As the yellow light generated by excitation by blue light is mixed, the light emitting device package 300 can provide white light.

Similarly, when the light emitting device 320 is a green light emitting diode, a magenta phosphor or blue and red phosphors (not shown) are mixed, and when the light emitting device 320 is a red light emitting diode, a cyan phosphor or blue light is used. The case where a green fluorescent substance is mixed is mentioned as an example.

Such phosphors (not shown) may be known such as YAG-based, TAG-based, sulfide-based, silicate-based, aluminate-based, nitride-based, carbide-based, nitridosilicate-based, borate-based, fluoride-based, and phosphate-based compounds.

Meanwhile, the first electrode 340 and the second electrode 350 may be mounted on the body 310. The first electrode 340 and the second electrode 350 may be electrically connected to the light emitting device 320 to supply power to the light emitting device 320.

The first electrode 340 and the second electrode 350 are electrically separated from each other, and may reflect light generated from the light emitting device 320 to increase light efficiency, and also generate heat generated from the light emitting device 320. Can be discharged to the outside.

Although the light emitting device 320 is mounted on the first electrode 350 in FIG. 8, the present invention is not limited thereto, and the light emitting device 320, the first electrode 340, and the second electrode 350 may be wire bonded. May be electrically connected by any one of the following methods, a flip chip method, and a die bonding method.

The first electrode 340 and the second electrode 350 are made of a metal material, for example, titanium (Ti), copper (Cu), nickel (Ni), gold (Au), chromium (Cr), and tantalum ( Ta, platinum (Pt), tin (Sn), silver (Ag), phosphorus (P), aluminum (Al), indium (In), palladium (Pd), cobalt (Co), silicon (Si), germanium ( Ge), hafnium (Hf), ruthenium (Ru), iron (Fe) may include one or more materials or alloys. In addition, the first electrode 340 and the second electrode 350 may be formed to have a single layer or a multi-layer structure, but is not limited thereto.

The light emitting device 320 is mounted on the first electrode 340 and may be a light emitting device that emits light such as red, green, blue, or white, or a UV (Ultra Violet) However, the present invention is not limited thereto. In addition, one or more light emitting devices 320 may be mounted.

In addition, the light emitting device 320 may be applied to a horizontal type in which all of its electrical terminals are formed on the upper surface, or to a vertical type or flip chip formed on the upper and lower surfaces.

Meanwhile, the light emitting device 320 according to the embodiment may include the first to fourth semiconductor layers (not shown), and thus may have resistance to ESD, thereby improving reliability and additionally using a separate zener device (not shown). Since it is avoided that the light emitting device package 300 is mounted in the light emitting device package 300, the light emitting efficiency of the light emitting device package 300 may be improved.

A plurality of light emitting device packages 300 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 300.

The light emitting device package 300, 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 light emitting device 100 or the light emitting device package 300 described in the above embodiments, for example, the lighting system may be a lamp, a street lamp. It may include.

9 is a perspective view illustrating a lighting system including a light emitting device according to an embodiment, and FIG. 10 is a cross-sectional view illustrating a D-D ′ section of the lighting system of FIG. 9.

That is, FIG. 10 is a cross-sectional view of the illumination system 400 of FIG. 9 cut in the plane of the longitudinal direction Z and the height direction X, and viewed in the horizontal direction Y. As shown in FIG.

9 and 10, the lighting system 400 may include a body 410, a cover 430 coupled to the body 410, and a closing cap 450 positioned at both ends of the body 410. have.

The lower surface of the body 410 is fastened to the light emitting device module 440, the body 410 is conductive and so that the heat generated from the light emitting device package 444 can be discharged to the outside through the upper surface of the body 410 The heat dissipation effect may be formed of an excellent metal material, but is not limited thereto.

In particular, the light emitting device package 444 according to the embodiment includes a light emitting device (not shown), and the light emitting device (not shown) includes the first to fourth semiconductor layers (not shown), thereby providing resistance to ESD. Since it can have a reliability, and also a separate zener device (not shown) is avoided to be mounted in the light emitting device package 444 to improve the luminous efficiency of the light emitting device package 444, and the illumination system 400 Can be.

The light emitting device package 444 may be mounted on the substrate 442 in multiple colors and in multiple rows to form a module. The light emitting device package 444 may be mounted at the same interval or may be mounted at various separation distances as necessary to adjust brightness. As the substrate 442, a metal core PCB (MCPCB) or a PCB made of FR4 may be used.

The cover 430 may be formed in a circular shape to surround the lower surface of the body 410, but is not limited thereto.

The cover 430 protects the light emitting device module 440 from the outside and the like. In addition, the cover 430 may include diffusing particles to prevent glare of the light generated from the light emitting device package 444 and to uniformly emit light to the outside, and may also include at least one of an inner surface and an outer surface of the cover 430. A prism pattern or the like may be formed on either side. In addition, a phosphor may be applied to at least one of an inner surface and an outer surface of the cover 430.

On the other hand, since the light generated from the light emitting device package 444 is emitted to the outside through the cover 430, the cover 430 should be excellent in the light transmittance, sufficient to withstand the heat generated in the light emitting device package 444 The cover 430 should be provided with heat resistance, and the cover 430 may include polyethylene terephthalate (PET), polycarbonate (PC), polymethyl methacrylate (PMMA), or the like. It may be formed of a material.

Closing cap 450 is located at both ends of the body 410 may be used for sealing the power supply (not shown). In addition, the closing cap 450 has a power pin 452 is formed, the lighting system 400 according to the embodiment can be used immediately without a separate device in the terminal from which the existing fluorescent lamps are removed.

11 is an exploded perspective view of a liquid crystal display including the light emitting device according to the embodiment.

11 is an edge-light method, the liquid crystal display 500 may include a liquid crystal display panel 510 and a backlight unit 570 for providing light to the liquid crystal display panel 510.

The liquid crystal display panel 510 may display an image by using light provided from the backlight unit 570. The liquid crystal display panel 510 may include a color filter substrate 512 and a thin film transistor substrate 514 facing each other with a liquid crystal interposed therebetween.

The color filter substrate 512 may implement colors of an image displayed through the liquid crystal display panel 510.

The thin film transistor substrate 514 is electrically connected to the printed circuit board 518 on which a plurality of circuit components are mounted through the driving film 517. The thin film transistor substrate 514 may apply a driving voltage provided from the printed circuit board 518 to the liquid crystal in response to a driving signal provided from the printed circuit board 518.

The thin film transistor substrate 514 may include a thin film transistor and a pixel electrode formed of a thin film on another substrate of a transparent material such as glass or plastic.

The backlight unit 570 may convert the light provided from the light emitting device module 520, the light emitting device module 520 into a surface light source, and provide the light guide plate 530 to the liquid crystal display panel 510. Reflective sheet for reflecting the light emitted from the rear of the light guide plate 530 and the plurality of films 550, 566, 564 to uniform the luminance distribution of the light provided from the 530 and improve the vertical incidence ( 540.

The light emitting device module 520 may include a PCB substrate 522 so that a plurality of light emitting device packages 524 and a plurality of light emitting device packages 524 may be mounted to form a module.

In particular, the light emitting device package 524 according to the embodiment includes a light emitting device (not shown), and the light emitting device (not shown) includes the first to fourth semiconductor layers (not shown), thereby providing resistance to ESD. Since it can have, the reliability is improved, and a separate zener element (not shown) is avoided to be mounted in the light emitting device package 524, so that the light emitting efficiency of the light emitting device package 524 and the backlight unit 570 can be improved. Can be.

Meanwhile, the backlight unit 570 includes a diffusion film 566 for diffusing light incident from the light guide plate 530 toward the liquid crystal display panel 510, and a prism film 550 for condensing the diffused light to improve vertical incidence. ), And may include a protective film 564 to protect the prism film 550.

12 is an exploded perspective view of a liquid crystal display including the light emitting device according to the embodiment. However, the parts shown and described in FIG. 11 will not be repeatedly described in detail.

12 illustrates a direct method, the liquid crystal display 600 may include a liquid crystal display panel 610 and a backlight unit 670 for providing light to the liquid crystal display panel 610.

Since the liquid crystal display panel 610 is the same as that described with reference to FIG. 11, a detailed description thereof will be omitted.

The backlight unit 670 may include a plurality of light emitting device modules 623, a reflective sheet 624, a lower chassis 630 in which the light emitting device modules 623 and the reflective sheet 624 are accommodated, and an upper portion of the light emitting device module 623. It may include a diffusion plate 640 and a plurality of optical film 660 disposed in the.

LED Module 623 A plurality of light emitting device packages 622 and a plurality of light emitting device packages 622 may be mounted to include a PCB substrate 621 to form a module.

In particular, the light emitting device package 622 according to the embodiment includes a light emitting device (not shown), and the light emitting device (not shown) includes the first to fourth semiconductor layers (not shown), thereby providing resistance to ESD. Since it can have a reliability, and also a separate zener device (not shown) is avoided to be mounted in the light emitting device package 622 to improve the light emitting efficiency of the light emitting device package 622 and the backlight unit 670 Can be.

The reflective sheet 624 reflects the light generated from the light emitting device package 622 in the direction in which the liquid crystal display panel 610 is positioned to improve light utilization efficiency.

On the other hand, the light generated from the light emitting device module 623 is incident on the diffusion plate 640, the optical film 660 is disposed on the diffusion plate 640. The optical film 660 includes a diffusion film 666, a prism film 650, and a protective film 664.

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 each embodiment 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.

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. It will be appreciated that various modifications and applications are possible. For example, each component specifically shown in the embodiments can be modified and implemented. It is to be understood that all changes and modifications that come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

Claims (9)

Board;
A first semiconductor layer disposed on the substrate;
A light emitting structure disposed on the first semiconductor layer and including an active layer between the second semiconductor layer, the third semiconductor layer, and the second and third semiconductor layers;
A fourth semiconductor layer disposed on the first semiconductor layer and separated from the light emitting structure;
Passivation disposed between the light emitting structure and the fourth semiconductor layer;
First electrodes disposed on the first and second semiconductor layers; And
And a second electrode disposed on the passivation and the third and fourth semiconductor layers. The method of claim 1,
The first and third semiconductor layers,
p-type dopant is doped,
The second and fourth semiconductor layers,
A light emitting device doped with an n-type dopant. The method of claim 1, wherein the thickness of the first semiconductor layer,
Is equal to the thickness of the third semiconductor layer,
Or a light emitting device smaller than the thickness of the third semiconductor layer. The thickness of the fourth semiconductor layer,
Is equal to the thickness of the second semiconductor layer,
Or a light emitting device smaller than the thickness of the second semiconductor layer. The method of claim 1, wherein the width of the second semiconductor layer,
A light emitting device smaller than the width of the first semiconductor layer. The method of claim 1, wherein the second semiconductor layer,
A light emitting device in which a step is formed. The method of claim 1, wherein the passivation,
The light emitting device disposed on an upper portion of the first semiconductor layer and disposed on side surfaces of the light emitting structure and the fourth semiconductor layer. Board;
A first semiconductor layer disposed on the substrate;
A light emitting structure disposed on the first semiconductor layer and including an active layer between the second semiconductor layer, the third semiconductor layer, and the second and third semiconductor layers;
A fourth semiconductor layer disposed on the first semiconductor layer and separated from the light emitting structure and positioned inside the light emitting structure;
Passivation disposed between the light emitting structure and the fourth semiconductor layer;
First electrodes disposed on the first and second semiconductor layers; And
And a second electrode disposed on the passivation and the third and fourth semiconductor layers. A light emitting device package comprising the light emitting device of any one of claims 1 to 8.

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