KR20130062769A

KR20130062769A - Light emitting device

Info

Publication number: KR20130062769A
Application number: KR1020110129199A
Authority: KR
Inventors: 황성민
Original assignee: 엘지이노텍 주식회사
Priority date: 2011-12-05
Filing date: 2011-12-05
Publication date: 2013-06-13

Abstract

The embodiment may include a first semiconductor structure including a first active layer, a first semiconductor layer including a first active layer, and a first semiconductor layer, a third semiconductor layer, and a third semiconductor layer between the first and second semiconductor layers. A light emitting structure comprising a second semiconductor structure disposed between a fourth semiconductor layer and the third and fourth semiconductor layers and including a second active layer having a quantum well having a different energy band gap from the quantum well of the first active layer; Any one of the first and second active layers is disposed between a first electrode electrically connected to the first and fourth semiconductor layers, a second electrode electrically connected to the second and third semiconductor layers, and the first and second semiconductor structures. It provides a light emitting device comprising a polarization layer for transmitting the light incident on the and reflecting and refracting the light incident on the other.

Description

[0001] LIGHT EMITTING DEVICE [0002]

The embodiment relates to a light emitting device.

LED (Light Emitting Diode) is a device that converts electrical signals into infrared, visible light or light using the characteristics of compound semiconductors. It is used in household appliances, remote controls, display boards, The use area of LED is becoming wider.

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.

On the other hand, since the LED has a rectifying characteristic of a general diode, when connected to an AC power source is repeated on / off according to the direction of the current does not generate light continuously, there is a risk of being damaged by the reverse current.

Therefore, in recent years, various researches for using LEDs directly connected to AC power sources have been conducted.

The embodiment provides a light emitting device which is easy to prevent loss of light emitted from the first and second semiconductor structures.

The light emitting device according to the embodiment is disposed on a first semiconductor structure including a first active layer, a first semiconductor layer including a first active layer, a second semiconductor layer, and the first and second semiconductor layers, and a third semiconductor structure. A second semiconductor structure disposed between the semiconductor layer, the fourth semiconductor layer and the third and fourth semiconductor layers, the second semiconductor structure including a second active layer having a quantum well having an energy band gap different from that of the quantum well of the first active layer; The light emitting structure is disposed between the first electrode electrically connected to the first and fourth semiconductor layers, the second electrode electrically connected to the second and third semiconductor layers, and the first and second semiconductor structures. It may include a polarized reflective layer that transmits the light incident from any one of the active layer, and reflects and refracts the light incident from the other.

The light emitting device according to the embodiment transmits the light incident on any one of the first and second semiconductor structures by disposing a polarization reflection layer causing polarized reflection between the first and second semiconductor structures, and transmits the light incident on the other. There is an advantage in that light loss can be suppressed by reflecting and refracting so as not to absorb light in any semiconductor structure.

In addition, the light emitting device according to the embodiment has an advantage of reducing the light efficiency variation with respect to the light emitted from the first and second semiconductor structures.

1 is a perspective view showing a light emitting device according to an embodiment.
2 is a cross-sectional perspective view showing a cut surface of the light emitting device shown in FIG.
3 is an enlarged view of 'A' illustrated in FIG. 2 according to an embodiment.
4 is a perspective view showing a light emitting device package including a light emitting device according to the embodiment.
5 is a perspective view showing a lighting apparatus including a light emitting device according to the embodiment.
6 is a cross-sectional view showing a cross-section AA of the lighting device of FIG.
7 is an exploded perspective view showing a first embodiment of a liquid crystal display including a light emitting device according to the embodiment.
8 is an exploded perspective view illustrating a second embodiment of a liquid crystal display including a light emitting device according to the embodiment.

Advantages and features of the inventive examples, and methods of achieving them will become apparent with reference to the embodiments described below in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be embodied in various forms, and the present embodiments are merely provided to make the disclosure of the present invention complete, and those of ordinary skill in the art to which the present invention pertains. It is provided to fully inform the scope of the invention, and the invention is defined only by the scope of the claims. Like reference numerals refer to like elements throughout.

The terms spatially relative, "below", "beneath", "lower", "above", "upper" May be used to readily describe a device or a relationship of components to other devices or components. Spatially relative terms should be understood to include, in addition to the orientation shown in the drawings, terms that include different orientations of the device during use or operation. For example, when flipping a device shown in the figure, a device described as "below" or "beneath" of another device may be placed "above" of another device. Thus, the exemplary term "below" can include both downward and upward directions. The device can also be oriented in other directions, so that spatially relative terms can be interpreted according to orientation.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. In the present specification, the singular form includes plural forms unless otherwise specified in the specification. It is noted that the terms "comprises" and / or "comprising" used in the specification are intended to be inclusive in a manner similar to the components, steps, operations, and / Or additions.

Unless otherwise defined, all terms (including technical and scientific terms) used in the present specification may be used in a sense that can be commonly understood by those skilled in the art. Also, commonly used predefined terms are not ideally or excessively interpreted unless explicitly defined otherwise.

The thickness and size of each layer in the drawings are exaggerated, omitted, or schematically shown for convenience and clarity of explanation. Also, the size and area of each component do not entirely reflect actual size or area.

Further, the angle and direction mentioned in the description of the structure of the light emitting device in the embodiment are based on those shown 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 perspective view showing a light emitting device according to the embodiment, Figure 2 is a sectional perspective view showing a cut surface of the light emitting device shown in Figure 1, Figure 3 is an enlarged view according to an embodiment 'A' shown in FIG. to be.

Referring to FIGS. 1 and 2, the light emitting device 100 may include a support member 110 and first and second semiconductor structures 120 and 130 having at least a portion thereof overlapped on the support member 110. .

The support member 110 is a translucent material, and may be formed of a conductive substrate or an insulating substrate. For example, sapphire (Al ₂ O ₃ ), SiC, Si, GaAs, GaN, ZnO, Si, GaP, InP, Ge, And Ga ₂ O ₃ .

The support member 110 may be wet-washed to remove impurities from the surface, and the support member 110 may be patterned with a light extraction pattern (Patterned SubStrate (PSS)) to improve the light extraction effect. It is not limited to this.

In addition, the support member 110 may be a material that can facilitate the release of heat to improve the thermal stability.

Meanwhile, an anti-reflection layer (not shown) may be disposed on the support member 110 to improve light extraction efficiency, and the anti-reflection layer is called an AR-anti-reflective coating layer, and is basically provided from a plurality of interfaces. The interference phenomenon between reflected light is used. That is, the phase of the light reflected from the other interface is shifted by 180 degrees to cancel each other, and the intensity of the reflected light is weakened. However, the present invention is not limited thereto.

The buffer layer 112 may be disposed on the support member 110 to mitigate lattice mismatch between the support member 110 and the first semiconductor structure 120 and to easily grow the plurality of semiconductor layers.

The buffer layer 112 may grow as a single crystal on the support member 110, and the buffer layer 112 grown as the single crystal may improve crystallinity of the semiconductor structure 120 growing on the buffer layer 112.

In addition, the buffer layer 112 may be formed of a structure including an AlInN / GaN stacked structure, an InGaN / GaN stacked structure, and an AlInGaN / InGaN / GaN stacked structure including AlN and GaN.

The light emitting structure (not shown) may be disposed on the support member 110.

In an embodiment, the light emitting structure may be divided into a plurality of light emitting cells (not shown), but is not limited thereto.

In this case, the light emitting structure may have a structure in which the first and second semiconductor structures 120 and 130 are stacked on each other.

The first semiconductor structure 120 may include a first active layer 124 between the first semiconductor layer 122, the second semiconductor layer 126, and the first and second semiconductor layers 122 and 126.

The second semiconductor structure 130 may include a second active layer 134 between the third semiconductor layer 132, the fourth semiconductor layer 136, and the third and fourth semiconductor layers 132 and 136. .

First, the first semiconductor layer 122 of the first semiconductor structure 120 may be disposed on the support member 110 or the buffer layer 112, and may be implemented as an n-type semiconductor layer.

In this case, when the first semiconductor layer 122 is a nitride-based semiconductor layer, for example, the composition formula of In _x Al _y Ga ₁ _-xy N (0≤x≤1, 0≤y≤1, 0≤x + y≤1) A semiconductor material having, for example, GaN, AlN, AlGaN, InGaN, InN, InAlGaN, AlInN and the like can be selected, for example, n-type dopants such as Si, Ge, Sn, Se, Te may be doped. .

In addition, when the first semiconductor layer 122 is a zinc oxide-based semiconductor layer, for example, In _x Al _y Zn _1-xy N (0 ≦ x ≦ 1, 0 ≦ y ≦ 1, 0 ≦ x + y ≦ 1), Semiconductor materials having a compositional formula, such as ZnO, AlO, AlZnO, InZnO, InO, InAlZnO. AlInO or the like, for example, n-type dopants such as Si, Ge, Sn, Se, Te may be doped.

The first active layer 124 may be disposed on the first semiconductor layer 122, and the first active layer 124 may be formed of a single or multiple quantum well structure or a quantum line using a compound semiconductor material of Group III-V elements. It may be formed of a quantum-wire structure, or a quantum dot structure.

The first active layer 124 when formed of a quantum well structure of the nitride-based semiconductor layer for _{example, In x Al y Ga 1 -x-} y N (0≤x≤1, 0 ≤y≤1, 0≤x + y≤ Single or both having a well layer having a compositional formula of 1) and a barrier layer having a compositional formula of In _a Al _b Ga _1-ab N (0 ≦ a ≦ ₁ , 0 ≦ b ≦ ₁ , 0 ≦ a + b ≦ 1) It may have a well structure.

In addition, the first active layer 124 when formed of a quantum well structure of a zinc oxide semiconductor layer for _{example, In x Al y Zn 1 -x-} y N (0≤x≤1, 0 ≤y≤1, 0≤x a barrier layer having a compositional formula of + well layers and _{in x Al y Zn 1 -x- y} N (0≤a≤1, 0 ≤b≤1, 0≤a + b≤1) having a composition formula of y≤1) It may have a single or quantum well structure having a.

The well layer may be formed of a material having a band gap smaller than the band gap of the barrier layer.

When the first active layer 124 has a multi-quantum well structure, each well layer (not shown) and a barrier layer (not shown) may have different compositions, thicknesses, and band gaps, but are not limited thereto.

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

Here, the first active layer 124 may vary the band gap by adjusting the composition ratio of Al or In, for example, when the Al is included, the band gap may be increased by increasing the composition ratio of Al, When In is included, the band gap can be increased by lowering the composition ratio of In.

In the embodiment, the light emitting device 100 is shown as a horizontal type, but may be used as a flip chip type.

The second semiconductor layer 126 may be disposed on the first active layer 124, and the second semiconductor layer 126 may be implemented as a p-type semiconductor layer that injects holes into the first active layer 124.

In this case, when the second semiconductor layer 126 is a nitride-based semiconductor layer, for example, the composition formula of In _x Al _y Ga ₁ _-xy N (0≤x≤1, 0≤y≤1, 0≤x + y≤1) A semiconductor material having, for example, GaN, AlN, AlGaN, InGaN, InN, InAlGaN, AlInN and the like can be selected, for example, p-type dopants such as Mg, Zn, Ca, Sr, Ba, etc. can be doped. .

In addition, when the second semiconductor layer 126 is a zinc oxide-based semiconductor layer, for example, In _x Al _y Zn _1-xy N (0 ≦ x ≦ 1, 0 ≦ y ≦ 1, 0 ≦ x + y ≦ 1), Semiconductor materials having a compositional formula, such as ZnO, AlO, AlZnO, InZnO, InO, InAlZnO. AlInO and the like, for example, p-type dopants such as Mg, Zn, Ca, Sr, Ba and the like can be doped.

The first semiconductor layer 122, the first active layer 124, and the second semiconductor layer 126 may be, for example, metal organic chemical vapor deposition (MOCVD) or chemical vapor deposition (CVD). Vapor Deposition, Plasma-Enhanced Chemical Vapor Deposition (PECVD), Molecular Beam Epitaxy (MBE), Hydride Vapor Phase Epitaxy (HVPE), Sputtering, etc. It may be formed using, but is not limited thereto.

In addition, the doping concentrations of the dopants in the first semiconductor layer 122 and the second semiconductor layer 126 may be uniformly or non-uniformly formed. That is, the plurality of semiconductor layers may be formed to have various doping concentration distributions, but the invention is not limited thereto.

In addition, the first semiconductor layer 122 may be implemented as a p-type semiconductor layer, the second semiconductor layer 126 may be implemented as an n-type semiconductor layer, and the n-type or p-type semiconductor is formed on the second semiconductor layer 126. A semiconductor layer (not shown) including a layer may be formed. Accordingly, the first light emitting structure 120 may have at least one of np, pn, npn, and pnp junction structures.

The third semiconductor layer 132 of the second semiconductor structure 130 may be disposed on the second semiconductor layer 126 of the first semiconductor structure 120, and is the same n-type semiconductor as the first semiconductor layer 122. It can be implemented in layers.

In addition, a second active layer 134 may be disposed on the third semiconductor layer 132, and a fourth semiconductor layer 136 may be disposed on the second active layer 134, and the fourth semiconductor layer 136 may be disposed on the second semiconductor layer 136. The semiconductor device may be implemented with the same p-type semiconductor layer as the semiconductor layer 126.

Here, the second active layer 134 may vary the composition ratio of Al or In, as described above, to have a band gap different from that of the first active layer 124.

Since the third and fourth semiconductor layers 132 and 136 and the second active layer 134 have the same structure as the first and second semiconductor layers 122 and 126 and the first active layer 124, description thereof is omitted.

Here, the first and second semiconductor structures 120 and 130 may be integrally formed, and the first and second semiconductor structures 120 and 130 may have different light generated from the first and second active layers 124 and 134. It may have a wavelength, and the amount of light may also vary.

The first and second semiconductor structures 120 and 130 may have different structures, materials, thicknesses, compositions, and sizes, but are not limited thereto.

Here, one side of the first and second semiconductor structures 120 and 130 may be mesa-etched to expose a portion of the first semiconductor layer 122, and one side of the second semiconductor structure 130 may be mesa-etched to form a third semiconductor. A portion of layer 132 may be exposed.

In this case, an insulating layer 160 may be formed on one side of the exposed first and second semiconductor structures 120 and 130 and one side of the second semiconductor structure 130.

In this case, the insulating layer 160 may prevent a short circuit between the semiconductor layers in the mesa-etched portions of each of the first and second semiconductor structures 120 and 130, and at least one of the first and second electrodes 142 and 144. One can be arranged.

That is, in the first electrode 142, the first semiconductor layer 122 and the second semiconductor structure 130 of the first semiconductor structure 120 may be electrically connected to the fourth semiconductor layer 136.

Here, when the light emitting device 100 is a flip chip type, the first electrode 142 may be disposed on the entire upper surface of the fourth semiconductor layer 136, and may be disposed on the side surface of the insulating layer 160. 1 may extend to an exposed area of the semiconductor layer 122.

In addition, the second electrode 144 is disposed on the other side of the second semiconductor structure 130, and is disposed in the exposed region of the third semiconductor layer 132 so that the second and third semiconductor layers 126 and 132 may be formed. Can be electrically connected.

In an embodiment, the first and second semiconductor structures 120 and 130 emit light from the first semiconductor structure 120 upon input of an ac power source, for example, a commercial AC power source. The second semiconductor structure 130 may be an ac-only light emitting device capable of emitting light when the power is input.

In the exemplary embodiment, the first electrode 142 is integrally shown on the first and fourth semiconductor layers 122 and 136, but may be separated from each other, but is not limited thereto.

In this case, a light transmissive electrode (not shown) may be disposed on the fourth semiconductor layer 136 of the second semiconductor structure 130, and a current applied to the first electrode 142 is uniformly applied to the light transmissive electrode. The pattern may be formed to be applied to the layer 136, but is not limited thereto.

In addition, the second electrode 144 may be formed on the second and third semiconductor layers 126 and 132 to apply power having the same polarity to the second and third semiconductor layers 126 and 132.

Meanwhile, a method of removing a part of the first and second light emitting structures 120 and 130 may use a predetermined etching method, but is not limited thereto. The etching method may be a wet etching method or a dry etching method.

The first and second electrodes 142 and 144 may be conductive materials, for example, In, Co, Si, Ge, Au, Pd, Pt, Ru, Re, Mg, Zn, Hf, Ta, Rh, Ir, W , Ti, Ag, Cr, Mo, Nb, Al, Ni, Cu, and may include a metal selected from WTi, or may include an alloy thereof, the metal material and IZO, IZTO, IAZO, IGZO, Translucent conductive materials such as IGTO, AZO, ATO, and the like may be included, but are not limited thereto.

In addition, at least one of the first and second electrodes 142 and 144 may have a single layer or a multi-layer structure, but is not limited thereto.

The polarized reflection layer 150 may be disposed between the first and second semiconductor structures 120 and 130.

The polarized reflection layer 150 has a predetermined thickness and may separate the first and second semiconductor structures 120 and 130.

In the embodiment, the polarized reflection layer 150 may supply power supplied to the second electrode 144 to the second semiconductor layer 126, and may include a hole when it includes an insulating material that cannot supply power. The insulating material may form a pattern so that power may be supplied to the second semiconductor layer 126, but is not limited thereto.

The polarized reflection layer 150 may be an undoped semiconductor layer. That is, the polarized reflection layer 150 may have low electrical conductivity because the p-type dopant or the n-type dopant is not doped.

The polarized reflection layer 150 may be disposed between the first and second semiconductor structures 120 and 130 to prevent diffusion and leakage current between the first and second semiconductor structures 120 and 130.

3, the reflective reflection layer 150 may have a multilayer structure including a plurality of layers 151, 152, 153, 154, and 155. In FIG. 3, a plurality of layers 151, 152, 153, 154, and 155 are formed, but the present disclosure is not limited thereto, and at least two layers may be formed.

The plurality of layers 151, 152, 153, 154, and 155 may have at least two different band gaps. For example, the polarized reflection layer 150 may have a structure in which a plurality of layers 151, 152, 153, 154, and 155 having different band gaps are repeatedly stacked alternately, but is not limited thereto.

The polarized reflection layer 150 may mitigate crystal defects caused by the lattice constant difference between the support member 110 and the first semiconductor layer 122. Such crystal defects tend to increase with the growth direction. The polarized reflection layer 150 includes a plurality of layers 151, 152, 153, 154, and 155 having different band gaps from each other, and is formed between the first light emitting structure 120 and the second light emitting structure 130. The propagation of crystal defects occurring in the lower reflection layer 150 may be blocked. Therefore, the polarized reflection layer 150 can suppress the transfer of crystal defects to the top. Therefore, the reliability and luminous efficiency of the light emitting device 100 can be improved.

On the other hand, the polarized reflection layer 150 is, for example, GaN, InN, InGaN, AlGaN, ZnO, AlO, AlZnO, InZnO, InO, InAlZnO. A semiconductor layer including AlInO may be included, and each layer may be disposed such that the layer having the smallest bandgap and the layer having the smallest bandgap are in contact with each other.

For example, the higher the composition of AlN, the larger the bandgap, and the higher the composition of InN, the smaller the bandgap, so that the bandgap of the layer containing InN is the lowest and the bandgap of the layer containing AlN can be the largest. have. Therefore, the layer containing AlN having the largest band gap and the layer containing InN having the smallest band gap can be formed in contact with each other.

On the other hand, the layer containing AlN having a small lattice constant generates tensile stress, and the layer containing InN having a large lattice constant may generate compressive stress. Therefore, when layers including AlN and layers including InN are alternately stacked, stress between layers can be alleviated.

The polarized reflective layer 150 may include a reflective material having a reflectance. Meanwhile, the plurality of layers 151, 152, 153, 154, and 155 may have at least two different refractive indices. The polarized reflection layer 150 may function as a distributed bragg reflector (DBR) layer having reflectance by including a plurality of layers 151, 152, 153, 154, and 155 having at least two different refractive indices.

That is, when the light emitting device 100 is disposed in a light emitting device package (not shown) in a flip chip type, a plurality of polarized reflection layers 150 may be adjacent to an active layer having a high band gap among the first and second active layers 124 and 134. The layers having the highest refractive index among the layers 151, 152, 153, 154, and 155 may be arranged so that the layers adjacent to the first active layer 124 may be stacked in the order of the highest refractive index and then the lowest refractive index.

In addition, at least one of the plurality of layers 151, 152, 153, 154, and 155 may include an insulating material, and may form a predetermined pattern.

In this case, the width (not shown) of the polarized reflection layer 150 may be the same as or wider than the width of the second active layer 134, and may be formed to be the same or narrower than the width of the first active layer 124. It does not limit to this.

The polarized reflection layer 150 has a polarization reflectivity, thereby transmitting the light of any one of the first and second active layers 124 and 134 and reflecting the other light, and is reflected by the polarized reflection layer 150. The light may travel in the lateral direction of one of the first and second semiconductor structures 120 and 130.

That is, the polarized reflection layer 150 reflects the light generated by the second semiconductor structure 130 without passing in the direction of the first semiconductor structure 120 and proceeds upward or laterally, thereby reducing light loss. have.

4 is a perspective view showing a light emitting device package including a light emitting device according to the embodiment.

4 is a transparent perspective view illustrating a part of the light emitting device package 300, and in the embodiment, the light emitting device package 300 is shown as a top view type, but may be a side view type, but is not limited thereto.

Referring to FIG. 4, the light emitting device package 300 may include a light emitting device 310 and a body 320 on which the light emitting device 310 is disposed.

The body 320 may include a first partition 322 disposed in a first direction (not shown) and a second partition 324 disposed in a second direction (not shown) that crosses the first direction. The first and second barrier ribs 322 and 324 may be integrally formed with each other, and may be formed by injection molding, an etching process, and the like.

That is, the first and second barrier ribs 322 and 324 may be formed of a resin material such as polyphthalamide (PPA), silicon (Si), aluminum (Al), aluminum nitride (AlN), AlO _x , and liquid crystal polymer (PSG). , photo sensitive glass, polyamide 9T (PA9T), neogeotactic polystyrene (SPS), metal, sapphire (Al ₂ O ₃ ), beryllium oxide (BeO), ceramic, and printed circuit board (PCB) It may be formed of at least one of).

The top shape of the first and second barrier ribs 322 and 324 may have various shapes such as triangles, squares, polygons, and circles, depending on the use and design of the light emitting device 310, but is not limited thereto.

In addition, the first and second partitions 322 and 324 form a cavity s in which the light emitting device 310 is disposed, and the cross-sectional shape of the cavity s may be formed in a cup shape, a concave container shape, or the like. The first and second partitions 322 and 324 constituting the cavity s may be inclined downward.

In addition, the planar shape of the cavity s may have various shapes such as triangles, squares, polygons, and circles, without being limited thereto.

First and second leadframes 313 and 314 may be disposed on the lower surface of the body 320, and the first and second leadframes 313 and 314 may be made of a metal material, for example, titanium (Ti) or copper. (Cu), nickel (Ni), gold (Au), chromium (Cr), tantalum (Ta), platinum (Pt), tin (Sn), silver (Ag), phosphorus (P), aluminum (Al), It may include one or more materials or alloys of indium (In), palladium (Pd), cobalt (Co), silicon (Si), germanium (Ge), hafnium (Hf), ruthenium (Ru), and iron (Fe). .

In addition, the first and second lead frames 313 and 314 may be formed to have a single layer or a multilayer structure, but the present invention is not limited thereto.

Inner surfaces of the first and second barrier ribs 322 and 324 are formed to be inclined at a predetermined inclination angle with respect to any one of the first and second lead frames 313 and 314, and the light emitting device 310 may be inclined according to the inclination angle. The reflection angle of the light emitted may vary, and thus the directivity angle of the light emitted to the outside may be adjusted. Concentration of the light emitted from the light emitting device 310 to the outside increases as the directivity of the light decreases, while concentration of the light emitted from the light emitting device 310 to the outside decreases as the directivity of the light increases.

The inner surface of the body 320 may have a plurality of inclination angles, but is not limited thereto.

The first and second lead frames 313 and 314 are electrically connected to the light emitting device 310, and are connected to the positive and negative poles of an external power source (not shown), respectively, to emit light of the light emitting device 310. ) Can be powered.

In an embodiment, the light emitting device 310 is disposed on the first lead frame 313, and the second lead frame 314 is described as being spaced apart from the first lead frame 313. Die-bonded with the first lead frame 313, wire-bonded by the second lead frame 314 and a wire (not shown), and may receive power from the first and second lead frames 313 and 314.

Here, the light emitting device 310 may be bonded to the first lead frame 313 and the second lead frame 314 with different polarities.

In addition, the light emitting device 310 may be wire-bonded or die-bonded to each of the first and second lead frames 313 and 314, and the connection method is not limited.

In the embodiment, the light emitting device 310 has been described as being disposed on the first lead frame 313, but is not limited thereto.

The light emitting device 310 may be adhered to the first lead frame 313 by an adhesive member (not shown).

Here, an insulating dam 316 may be formed between the first and second lead frames 313 and 314 to prevent electrical shorts (shorts) of the first and second lead frames 313 and 314.

In an embodiment, the insulating dam 316 may be formed in a semicircular shape, but the embodiment is not limited thereto.

A cathode mark 317 may be formed on the body 313.

The light emitting device 310 may be a light emitting diode. The light emitting diode may be, for example, a colored light emitting diode emitting red, green, blue, or white light, or an ultraviolet (UV) emitting diode emitting ultraviolet light, but is not limited thereto. A plurality of light emitting devices 310 may be mounted on the frame 313, and at least one light emitting device 310 may be mounted on the first and second lead frames 313 and 314, respectively. The number and mounting positions of 310 are not limited.

The body 320 may include a resin 318 filled in the cavity s. That is, the resin material 18 may be formed in a double molding structure or a triple molding structure, but is not limited thereto.

In addition, the resin material 318 may be formed in a film form, and may include at least one of a phosphor and a light diffusing material, and a translucent material that does not include the phosphor and the light diffusing material may be used. Do not.

5 is a perspective view illustrating a lighting apparatus including a light emitting device according to an embodiment, and FIG. 6 is a cross-sectional view illustrating an A-A cross section of the lighting apparatus of FIG. 5.

In order to describe the shape of the illumination device 400 according to the embodiment in detail, the longitudinal direction Z of the illumination device 400, the horizontal direction Y perpendicular to the longitudinal direction Z, The direction Z and the horizontal direction Y and the vertical direction X perpendicular to the horizontal direction Y will be described.

That is, FIG. 6 is a cross-sectional view of the lighting apparatus 400 of FIG. 5 cut in the plane in the longitudinal direction Z and the height direction X, and viewed in the horizontal direction Y. As shown in FIG.

5 and 6, the lighting device 400 may include a body 410, a cover 430 fastened to the body 410, and a closing cap 450 positioned at both ends of the body 410. have.

The light emitting device module 440 is fastened to the lower surface of the body 410, and the body 410 is conductive so that heat generated from the light emitting device package 444 can be discharged to the outside through the upper surface of the body 410. And it may be formed of a metal material having an excellent heat dissipation effect.

The light emitting device package 444 has roughness (not shown) formed on each lead frame (not shown), so that the reliability and luminous efficiency of bonding can be improved, and it is advantageous to design a slim and compact display device.

The light emitting device package 444 may be mounted on the PCB 442 in multiple colors and in multiple rows to form an array. The light emitting device package 444 may be mounted at the same interval or may be mounted with various separation distances as necessary to adjust brightness. As the PCB 442, a metal core PCB (MPPCB) 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 have excellent light transmittance, and has sufficient heat resistance to withstand the heat generated from the light emitting device package 444. The cover 430 is preferably formed of a material including polyethylene terephthalate (PET), polycarbonate (PC), polymethyl methacrylate (PMMA), or the like. .

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 fin 450 is formed on the finishing cap 450, so that the lighting device 400 according to the embodiment can be used immediately without a separate device on the terminal from which the conventional fluorescent lamp is removed.

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

7, 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 in an edge-light manner.

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 the 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 light emitting device array including a PCB substrate 522 such that a plurality of light emitting device packages 524 and a plurality of light emitting device packages 524 are mounted to form an array.

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.

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

However, FIG. 8 will not be described in detail repeatedly with reference to FIG. 7.

8 is a direct view, the liquid crystal display device 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. 7, 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 an array.

In particular, in the light emitting device package 622, roughness 170 is formed in a region where wires are bonded by the light source 130 and the wires 150 to the lead frames 140 and 142, thereby improving the reliability of the bonding. Improved, slim, compact and more reliable backlight unit 670 can be implemented.

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.

Here, the lighting device 400 and the liquid crystal display device 500 and 600 may be included in the lighting system. In addition, the lighting device 400 may include a light emitting device package, and a lighting device may be included in the lighting system.

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.

100: light emitting element 110: support member
120: first semiconductor structure 130: second semiconductor structure
150: polarized reflection layer 300: light emitting device package

Claims

A first semiconductor structure including a first active layer between the first semiconductor layer, the second semiconductor layer, and the first and second semiconductor layers and the first semiconductor structure, the third semiconductor layer and the fourth semiconductor layer; A light emitting structure disposed between the third and fourth semiconductor layers, the light emitting structure including a second semiconductor structure including a second active layer having a quantum well having a different energy band gap from the quantum well of the first active layer;
A first electrode electrically connected to the first and fourth semiconductor layers;
A second electrode electrically connected to the second and third semiconductor layers; And
And a polarized reflection layer disposed between the first and second semiconductor structures and transmitting the light incident from one of the first and second active layers, and reflecting and refracting the light incident from the other.

The method of claim 1, wherein the polarized reflective layer,
A light emitting device comprising at least one stacked pair comprising a first layer and a second layer having a higher refractive index than the first layer.

3. The method of claim 2,
The quantum well of the first active layer,
Has a higher energy band gap than the quantum well of the second active layer,
The second layer,
A light emitting device disposed adjacent to the first active layer.

3. The method of claim 2,
The first layer is,
AlGaN,
The second layer,
At least one of GaN and AlN.

3. The method of claim 2,
The polarized reflection layer,
A third layer on the second layer;
The third layer,
A light emitting device comprising an insulating material and having a predetermined pattern.

The width of the polarized reflective layer,
Is equal to the width of the second active layer,
Or a light emitting device wider than the width of the second active layer.

The method of claim 1, wherein the polarized reflective layer,
Is equal to the width of the first active layer,
Or a light emitting device narrower than the width of the first active layer.

The method of claim 1,
The first and second active layers,
A light emitting device comprising at least one of Al and In.

The method of claim 8,
The first active layer,
The concentration of Al is higher than that of the second active layer,
Or a light emitting device having a lower In concentration than the second active layer.

The method of claim 1,
And a support member for supporting the first semiconductor structure.

The method of claim 8, wherein the support member,
Light emitting device made of a light-transmissive material.

The method of claim 1, wherein at least one of the first and second electrodes,
Light emitting device consisting of a multilayer structure.

The method of claim 1,
And an insulating layer disposed on at least one side of the first and second semiconductor structures.
Wherein the second electrode comprises:
A light emitting device disposed on a side of the insulating layer and electrically connected to the first and fourth semiconductor layers.

An illumination system comprising the light emitting element of any one of claims 1 to 13.