KR20150012552A - Light emitting device - Google Patents

Abstract

A light emitting device according to an embodiment includes a substrate, a first conductivity type semiconductor layer on the substrate, an active layer on the first conductivity type semiconductor layer, and a second conductivity type semiconductor layer on the active layer. The first conductivity type semiconductor layer includes a first layer which has an upper side with recessed first curvature parts, a second layer on the first layer, and a third layer arranged on the second layer. The first layer is doped with an impurity. The second layer is an undoped layer which is not doped with an impurity. The third layer may include InAlGaN.

Description

[0001]

An embodiment relates to a light emitting element.

A light emitting device (LED) is an element that converts an electric signal into an infrared ray, a visible light or a light by utilizing the characteristics of a compound semiconductor. It is used in household electric appliances, remote controllers, display boards, The use area of LED is becoming wider.

In general, a light emitting device that is miniaturized is made of a surface mount device for mounting directly on a PCB (Printed Circuit Board) substrate, and thus a light emitting device used as a display device is also developed as a surface mount device type have. Such a surface mount device can replace a conventional simple lighting lamp, and can be used as a lighting indicator for displaying various colors, a character indicator, an image indicator, and the like.

On the other hand, due to a large lattice mismatch between the substrate and the semiconductor layer, crystal defects such as dislocation may be formed in the semiconductor layer. Such crystal defects increase the leakage current of the light emitting device, The active layer of the light emitting device can be destroyed by a strong field. Therefore, in order to utilize the light emitting device in a lighting device or the like, resistance to electrostatic discharge (ESD) of a certain level or more is required.

And a light emitting element having resistance to electrostatic discharge and having improved luminous efficiency.

The light emitting device according to the embodiment includes a substrate, a first conductive semiconductor layer on the substrate, an active layer on the first conductive semiconductor layer, and a second conductive semiconductor layer on the active layer, A second layer disposed on the first layer, and a third layer disposed on the second layer, wherein the first layer is doped with impurities , The second layer is an undoped layer not doped with an impurity, and the third layer may include InAlGaN.

The embodiment reduces the leakage current due to dislocation and can improve resistance to electrostatic discharge.

In addition, the third layer includes InAlGaN, which has the advantage of alleviating the stress generated between the third layer and the active layer while freely adjusting the size of the third indentation formed on the potential.

In addition, since the size of the third indentation can be easily controlled, it is possible to prevent the dislocations generated by the first through third indentations from being transmitted to the active layer and the second semiconductor layer, thereby improving the quality of the light emitting device.

Further, the size of the third indented portion can be adjusted to reduce the size of the concave portion formed by the shape of the third indented portion on the upper surface of the active layer, thereby increasing the light emitting area and increasing the luminous efficiency.

1 is a plan view showing a light emitting device according to an embodiment of the present invention,
FIG. 2A is a cross-sectional view taken along line AA of FIG. 1,
FIG. 2B is a cross-sectional view taken along line BB of FIG. 2A,
FIG. 2C is a cross-sectional view taken along line CC of FIG. 2A,
FIG. 3 is an enlarged cross-sectional view of the area D of FIG. 2A,
4 is a reference view for explaining a first indentation on a first layer according to an embodiment,
5 is a perspective view illustrating a light emitting device package including the light emitting device according to the embodiment,
6 is a cross-sectional view illustrating a light emitting device package including the light emitting device according to the embodiment.
7 is an exploded perspective view of a display device including a light emitting device according to an embodiment,
8 is a cross-sectional view of the display device of Fig. 7,
9 is an exploded perspective view of a lighting device including a light emitting device according to an embodiment.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention and the manner of achieving them will become apparent with reference to the embodiments described in detail below with reference to the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. To fully disclose the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims. Like reference numerals refer to like elements throughout the specification.

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 inverting an element shown in the figures, an element described as "below" or "beneath" of another element may be placed "above" another element. Thus, the exemplary term "below" can include both downward and upward directions. The elements can also be oriented in different directions, so that spatially relative terms can be interpreted according to orientation.

The terminology used herein is for the purpose of illustrating embodiments and is not intended to be limiting of the present 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 defined otherwise, all terms (including technical and scientific terms) used herein may be used in a sense commonly understood by one of ordinary skill in the art to which this invention belongs. 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.

FIG. 1 is a plan view of a light emitting device according to an embodiment of the present invention, FIG. 2 is a cross-sectional view taken along the line AA in FIG. 1, FIG. 2 b is a cross- FIG. 2C is a cross-sectional view taken along the line CC in FIG. 2A, FIG. 3 is an enlarged cross-sectional view of the D region in FIG. 2A, and FIG. 4 is a cross- .

1 to 4, a light emitting device 100 according to an embodiment includes a substrate 110, a first conductive semiconductor layer 120 on the substrate 110, an active layer (not shown) on the first conductive semiconductor layer 120, The first conductive semiconductor layer 120 may include a first layer 121, a second layer 123, and a third layer 125. The first conductive semiconductor layer 120 may be formed on the active layer 130, ).

Further, it may further include a strain relief layer 135 disposed between the third layer 125 and the active layer 130.

The substrate 110 may be formed of any material having optical transparency, for example, sapphire (Al ₂ O ₃ ), GaN, ZnO, or AlO, but is not limited thereto. In addition, the substrate 110 may be formed of a carrier wafer, a material suitable for semiconductor material growth. A SiC substrate having a higher thermal conductivity than a sapphire (Al ₂ O ₃ ) substrate or an SiC substrate including Si, GaAs, GaP, InP, Ga ₂ O ₃ can be used.

Although not shown, a buffer layer (not shown) may be formed on the substrate 110 to mitigate lattice mismatch between the substrate 110 and the first conductive semiconductor layer 120. The buffer layer (not shown) may be grown as a single crystal on the substrate 110 and the buffer layer (not shown) grown by a single crystal may improve the crystallinity of the first conductive semiconductor layer 120 grown on the buffer layer .

The buffer layer (not shown) may be a semiconductor material having a composition formula of In _x Al _y Ga _(1-xy ) N (0? X? 1, 0? _Y? 1, 0? _X + InN, AlN, AlInN, InGaN, AlGaN, and InAlGaN.

The first conductive semiconductor layer 120 may be formed of a semiconductor compound and may be doped with a first conductive dopant. For example, the first conductive semiconductor layer 120 may be formed of an n-type semiconductor layer to provide electrons to the active layer 140. The first conductive semiconductor layer 120 is a semiconductor material having a composition formula of In _x Al _y Ga _1-xy N (0? X? 1, 0? _Y? 1, 0? _X + y? 1) , AlN, AlGaN, InGaN, InN, InAlGaN, AlInN and the like, and n-type dopants such as Si, Ge, Sn, Se and Te can be doped.

The first conductive semiconductor layer 120 may include a first layer 121, a second layer 123 and a third layer 125. The first layer 121 may have a concave And may include a first indentation 122.

The first layer 121 may be a layer doped with an n-type dopant, and the first indent 122 may be formed by temperature control during growth of the first layer 121.

For example, when the first layer 121 is grown at a temperature of 550 to 940 ° C. and a pressure of 100 to 500 torr, the first indented portion 122 may be formed on the upper surface of the first layer 121.

The first layer 121 is grown at a high temperature of 1000 ° C or higher at the initial stage of growth, and when the growth temperature is lowered to 550 to 940 ° C at the final stage of growth, a first indent 122 is formed. At the initial stage of the growth of the first layer 121, the GaN source (TGMA or the like), the N source (NH3 or the like), H ₂ or the like are supplied and the growth temperature The first indentation 122 is formed by lowering the temperature to 550 to 940 ° C and stopping or reducing the Ga source and the N source.

Meanwhile, since the first conductive semiconductor layer 120 is grown from a semiconductor material having a composition formula of In _x Al _y Ga _1-xy N (0? X? 1, 0? _Y? 1, 0? _X + y? 1) The first depressed portion 122 is formed by a first inclined plane 1, a second inclined plane 1, a second inclined plane 2, 1, 0, 2) and the second inclined plane (-1, 1, 0, 2). Further, the first indenting portion 122 may have a hexagonal shape when viewed from a plane. That is, the first indented portion 122 may have the shape of a wedge or a hexagonal horn (hexagonal). The shape of the first depressed portion 122 is not limited to this. For example, the shape of the first depressed portion 122 may be semicircular, circular, polygonal, or the like.

In general, the nitride semiconductor layer and its composites are most stable in a hexagonal crystal structure (especially a hexagonal wurzite structure). In the semiconductor growth process, when the temperature is changed or the source in the chamber is changed, a defect is generated without having a stable structure of the nitride semiconductor layer. This defect is stably formed at the portion where the potential 190 is formed, Thereby forming an indentation 122. The shape of the first indenting portion 122 is generally hexagonal (hexagonal) because of the hexagonal crystal structure of the nitride semiconductor layer. In addition to this, the shape of various indentations .

The first depressed portion 122 is selectively formed in a portion where the potential 190 is formed and the first depressed portion 122 is formed such that the resistance R ₂ of the apex portion is the growth surface of the first layer 121 ( ₀ , ₀ , ₀ , ₁ ), the resistance at the site where the potential 190 is generated can be increased. Therefore, when the static electricity is applied, the current concentrated through the potential 190 is cut off, and the leakage current due to the potential 190 is reduced, so that the electrostatic discharge (ESD) immunity of the light emitting device 100 can be improved. At this time, the current can move through the growth plane (0, 0, 0, 1) of the first layer 121 having a low resistance and excellent crystallinity.

The first indentation 122 formed on the top surface of the first layer 121 may be vertically overlapped on the potential 190 formed in the first layer 121. Further, one end of the potential 190 may be in contact with the vertex of the first indentation 122. Here, the meaning of "vertically overlapped" may mean overlapping along the up and down directions with reference to Fig.

The first indentation 122 may be irregularly arranged on the upper surface of the first layer 121, but the present invention is not limited thereto.

The second layer 123 may be deposited on the first layer 121. The second layer 123 may be an undoped layer that is not doped with impurities. The second layer 123 may include a second indent 124 formed at a position vertically overlapping the first indent 122.

The second indented portion 124 may be formed on the first indented portion 122 to have a shape corresponding to the first indented portion 122. The second indented portion 124 may be formed by the shape of the first indented portion 122 in the process of stacking the second layer 123.

For example, as shown in Fig. 3, the second indented portion 124 may have a cross-sectional shape of "V" and may have a hexagonal shape in plan view. That is, the second indentation 124 may have the shape of a wedge or hexagonal horn. The shape of the second indent portion 124 is not limited to this, and for example, a shape in cross section and plan view can be formed in a semicircular shape, a circular shape, a polygonal shape, or the like.

The size of the second indenting portion 124 may be larger than that of the first indenting portion 122. Here, the sizes of the first indent portion 122 and the second indent portion 124 may mean width, depth, volume, and the like.

For example, the depth of the second indentation 124 formed on the first indentation 122 may be greater than the depth of the first indent 122. The width L2 of the second indented portion 124 formed on the first indented portion 122 may be larger than the width L1 of the first indented portion 122. [

The third layer 125 is deposited on the second layer 123. The third layer 125 may include a third indentation 126 formed at a position vertically overlapping the second indentation 124.

The third layer 125 may be formed of In _x Al _y Ga _1-xy N (0? X? 1, 0? _Y? 1, 0? _X + y? 1). For example, the third layer 125 may be formed at a temperature of 900 캜 or higher, including InAlGaN. It is possible to control the size of the third indent portion 126 through the control of the doping concentration of In and Al of the InAlGaN included in the third layer 125 and the thickness of the third layer 125. [

Al (aluminum) of the third layer 125 may fill the second indented portion 124 formed on the first indented portion 122 because of a small lattice size. Accordingly, the size of the third indented portion 126 can be adjusted by adjusting the content of Al (aluminum silver) and the thickness of the third layer 125. [

The doping concentration of Al (aluminum) doped in the third layer 125 may be 6% to 10%. When the doping concentration of Al (aluminum) in the third layer 125 is less than 6%, the effect of filling the second indenting portion 124 is small and the Al (aluminum) doping concentration of the third layer 125 is less than 10% The tensile stress is increased, and the quality of the light emitting device may be deteriorated.

In (Indium) of the third layer 125 can relax stress caused by a difference in lattice constant between the third layer 125 and the active layer 130.

The doping concentration of In (indium) doped in the third layer 125 may be 2% to 5%. When the In (indium) doping concentration of the third layer 125 is less than 2%, the stress relaxation effect is small and when the In (indium) doping concentration of the third layer 125 is more than 5% There is a problem that the quality of the magnetic recording medium is deteriorated and a spiral is formed.

Therefore, when the third layer 125 is formed to include InAlGaN, the size of the third indentation 126 formed on the potential 190 through the adjustment of the doping concentration of In (indium) and Al (aluminum) There is an advantage that the stress generated between the active layers 130 is relaxed while being freely adjusted. The third layer 125 may include AlGaN instead of InAlGaN, but is not limited thereto.

The size of the third recessed portion 126 may be adjusted so that the dislocations 190 generated by the first through third recessed portions 126 are transferred to the active layer 130 and the second semiconductor layer 150 And the quality of the light emitting device can be improved.

The size of the third indented portion 126 can be adjusted to reduce the size of the fifth indented portion 131 formed by the shape of the third indented portion 126 on the top surface of the active layer 130, Thereby increasing the area and increasing the luminous efficiency.

The size of the third indentation 126 may also be determined by the thickness of the third layer 125. For example, the thickness of the third layer 125 may be in the range of 2 nm to 20 nm. If the thickness of the third layer 125 is less than 2 nm, the size of the third indentation 126 may be increased, and the current diffusion effect may be reduced, thereby decreasing the luminous efficiency. If the thickness of the third layer 125 is thicker than 20 nm, the second indentation 124 may be completely filled.

The third indented portion 126 may be formed on the second indented portion 124 to have a shape corresponding to the second indented portion 124. The third indented portion 126 may be formed by the shape of the second indented portion 124 in the process of stacking the third layer 125.

For example, as shown in Fig. 3, the third indentation 126 may have a cross section of a "V" shape, and may have a hexagonal shape when seen in plan view. That is, the third indentation 126 may have the shape of a wedge or a hexagonal horn. The shape of the third indent portion 126 is not limited to this, and for example, the shape seen from a cross section and a plane can be formed into a semicircular shape, a circular shape, a polygonal shape, or the like.

On the other hand, the size of the third indenting portion 126 may be larger than that of the second indenting portion 124. That is, the size of the second indent portion 124 may be smaller than that of the third indent portion 126.

The width L3 of the third indented portion 126 formed on the second indented portion 124 may be larger than the width L2 of the second indented portion 124. [

Here, the sizes of the first and third indentations 126 are concepts including the width, depth, or volume of the indentation.

The strain relief layer 135 is disposed between the third layer 125 and the active layer 130.

For example, the strain relieving layer 135 may be a multilayer structure formed of In _y Al _x Ga _(1-xy) N (0 x 1, 0 y 1, 0 x + y 1) Lt; / RTI >

The stress relieving layer 135 can effectively relax stresses due to lattice mismatch between the first conductive semiconductor layer 121 and the active layer 130.

Further, since the strain relaxation layer 135 is repeatedly laminated in at least five cycles having the composition of the first In _x1 GaN and the second In _x2 GaN, more electrons are collected at the low energy level of the active layer 130, The probability of recombination of electrons and holes increases and the luminous efficiency can be improved.

The strain relief layer 135 may include a fourth indented portion 128 formed at a position vertically overlapping the third indented portion 126.

For example, the fourth indented portion 128 may be formed in a shape corresponding to the third indented portion 126 at a position vertically overlapping the third indented portion 126. In addition, the size (width, depth, volume) of the fourth indentation 128 may be smaller than the size of the third indentation 126. The width L4 of the fourth indent portion 128 may be smaller than the width L3 of the third indent portion 126. [

The thickness of the strain relief layer 135 may be in the range of 20 nm to 30 nm. When the thickness of the strain relief layer 135 is less than 20 nm, the size of the fourth indentation 128 can be increased, so that the size of the fifth indentation 131 formed in the active layer 130 can not be reduced, As a result, the current diffusion effect may be reduced and the luminous efficiency may be deteriorated. If the thickness of the strain relief layer 135 is thicker than 30 nm, the third indented portion 126 may be completely filled.

The active layer 130 is disposed on the strain relief layer 135.

The active layer 130 is a region where electrons and holes are recombined. As the electrons and the holes are recombined, the active layer 130 transits to a low energy level and can generate light having a wavelength corresponding thereto.

The active layer 130 may be formed of a single or multiple quantum well structure, a quantum-wire structure, a quantum dot structure, or the like using a compound semiconductor material of Group 3-V group elements.

When the active layer 130 has a quantum well structure, for example, a well layer having a composition formula of In _x Al _y Ga _1-xy N (0? X? 1, 0? _Y? 1, 0? _X + y? 1) And a barrier layer having a composition formula of In _a Al _b Ga _1-ab N (0? A? 1, 0? B? 1, 0? A + b? 1). The well layer may be formed of a material having a band gap smaller than the band gap of the barrier layer.

For example, the active layer 130 having a multiple quantum well structure may be formed by repeatedly laminating InGaN and GaN, and may be formed by repeatedly stacking AlGaN and GaN. Here, depending on the type of the material of the active layer 130, the emission wavelength generated by the combination of electrons and holes is changed, so that the semiconductor material included in the active layer 130 can be controlled according to a target wavelength.

A fifth indented portion 131 may be formed on the upper surface of the active layer 130 at a position corresponding to the fourth indented portion 128 and formed by the shape of the fourth indented portion 128.

The fifth depressed portion 131 is located on the upper surface of the active layer 130. The fifth depressed portion 131 may be selectively formed at a position vertically overlapping the fourth depressed portion 128.

The fifth depressed portion 131 may be formed by stacking the active layer 130 according to the shape of the fourth depressed portion 128.

The fifth indentation 131 may have a shape corresponding to the fourth indentation 128.

The size of the fifth depressed portion 131 may be smaller than that of the fourth depressed portion 128.

For example, the width L5 of the fifth depressed portion 131 may be smaller than the width L4 of the fourth depressed portion 128.

Therefore, the thickness and the composition of the third layer 125 or the strain relief layer 135 may be adjusted to reduce the size of the fifth indentation 131 formed on the upper surface of the active layer 130. The size of the fifth recessed portion 131 formed on the upper surface of the active layer 130 is reduced so that the non-emitting region is reduced in the active layer 130. Thus, Can be effectively blocked.

The thickness of the active layer 130 may be in the range of 20 nm to 40 nm. If the thickness of the active layer 130 is less than 20 nm, the emission region may be reduced. If the thickness of the active layer 130 is thicker than 40 nm, the fourth indentation 128 may be completely buried.

A second conductive semiconductor layer 140 may be formed on the active layer 130. The second conductive semiconductor layer 140 may be formed of a semiconductor compound and may be doped with a second conductive dopant. For example, the second conductive semiconductor layer 140 may be formed of a p-type semiconductor layer doped with a p-type dopant such as Mg, Zn, Ca, Sr, or Ba, have. The second conductive semiconductor layer 140 is a semiconductor material having a composition formula of In _x Al _y Ga _1-xy N (0? X? 1, 0? _Y? 1, 0? _X + y? 1) , AlN, AlGaN, InGaN, InN, InAlGaN, AlInN and the like.

The second conductive semiconductor layer 140 may be formed on the active layer 130 to fill the fifth recessed portion 131 formed on the active layer 130.

The second conductive semiconductor layer 140 covers the fifth recessed portion 131 to effectively block the electric potential due to the first through fifth recessed portions formed up to the active layer 130. As a result, .

An intermediate layer (not shown) may be formed between the active layer 130 and the second conductive semiconductor layer 140. The intermediate layer may be injected from the first conductive semiconductor layer 120 into the active layer 130 when a high current is applied An electron blocking layer may be used to prevent the electrons from being recombined in the active layer 130 and flowing to the second conductive semiconductor layer 140. The intermediate layer has a band gap relatively larger than that of the active layer 130 so that electrons injected from the first conductive semiconductor layer 120 are injected into the second conductive semiconductor layer 140 without being recombined in the active layer 130 . Accordingly, the probability of recombination of electrons and holes in the active layer 130 can be increased and the leakage current can be prevented.

Meanwhile, the above-described intermediate layer may have a bandgap larger than the bandgap of the barrier layer included in the active layer 130, and may be formed of a semiconductor layer containing Al, such as p-type AlGaN, but is not limited thereto .

The first conductive semiconductor layer 120, the active layer 130 and the second conductive semiconductor layer 140 may be formed using a metal organic chemical vapor deposition (MOCVD) method, a chemical vapor deposition (CVD) method, (PECVD), molecular beam epitaxy (MBE), and hydride vapor phase epitaxy (HVPE), which can be used to form And is not limited thereto.

A third conductive semiconductor layer (not shown) including an n-type or p-type semiconductor layer may be formed on the second conductive semiconductor layer 140. The light emitting element 100 may include np, pn, npn, and a pnp junction structure.

In addition, the doping concentrations of the conductive dopants in the first conductive semiconductor layer 120 and the second conductive semiconductor layer 140 may be uniform or non-uniform. That is, the structure of the plurality of semiconductor layers may be variously formed, but the structure is not limited thereto.

The active layer 130 and the second conductive semiconductor layer 140 are partially removed to expose a part of the first conductive semiconductor layer 120 and the first electrode 160 is formed on the exposed first conductive semiconductor layer 120 .

The light transmitting electrode layer 150 may be formed on the second conductive semiconductor layer 140 and the second electrode 152 may be formed on the light transmitting electrode layer 150.

The first electrode 160 and the second electrode 152 may be formed of a conductive material such as In, Co, Si, Ge, Au, Pd, Pt, Ru, Re, Mg, Zn, Hf, W, Ti, Ag, Cr, Mo, Nb, Al, Ni, Cu, and WTi.

The transparent electrode layer 150 may be formed of ITO, IZO (In-ZnO), GZO (Ga-ZnO), AZO (Al-ZnO), AGZO / ITO, Ni / IrOx / Au, and Ni / IrOx / Au / ITO, and is formed on the second conductive semiconductor layer 140, thereby preventing current clustering.

FIG. 5 is a perspective view illustrating a light emitting device package including the light emitting device according to the embodiment, and FIG. 6 is a cross-sectional view illustrating a light emitting device package including the light emitting device according to the embodiment.

5 and 6, the light emitting device package 500 includes a body 510 having a cavity 520, first and second lead frames 540 and 550 mounted on the body 510, A light emitting device 530 electrically connected to the first and second lead frames 540 and 550 and an encapsulant (not shown) encapsulated in the cavity 520 to cover the light emitting device 530.

The body 510 may be made of a resin material such as polyphthalamide (PPA), silicon (Si), aluminum (Al), aluminum nitride (AlN), liquid crystal polymer (PSG), polyamide 9T (SPS), a metal material, sapphire (Al2O3), beryllium oxide (BeO), and a printed circuit board (PCB). The body 510 may be formed by injection molding, etching, or the like, but is not limited thereto.

The inner surface of the body 510 may be formed with an inclined surface. The reflection angle of the light emitted from the light emitting device 530 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 controlled.

Concentration of light emitted to the outside from the light emitting device 530 increases as the directivity angle of light decreases. Conversely, as the directivity angle of light increases, the concentration of light emitted from the light emitting device 530 decreases.

The shape of the cavity 520 formed in the body 510 may be circular, rectangular, polygonal, elliptical, or the like, and may have a curved shape, but the present invention is not limited thereto.

The light emitting element 530 is mounted on the first lead frame 540 and may be a light emitting element 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 elements 530 may be mounted.

The light emitting device 530 may be a horizontal type or a vertical type formed on the upper or lower surface of the light emitting device 530 or a flip chip Applicable.

The encapsulant (not shown) may be filled in the cavity 520 to cover the light emitting device 530.

The encapsulant (not shown) may be formed of silicon, epoxy, or other resin material. The encapsulant may be filled in the cavity 520 and ultraviolet or thermally cured.

In addition, the encapsulant (not shown) may include a phosphor, and the phosphor may be selected to be a wavelength of light emitted from the light emitting device 530 so that the light emitting device package 500 may emit white light.

The phosphor may be one of a blue light emitting phosphor, a blue light emitting phosphor, a green light emitting phosphor, a sulfur green light emitting phosphor, a yellow light emitting phosphor, a yellow red light emitting phosphor, an orange light emitting phosphor, and a red light emitting phosphor depending on the wavelength of light emitted from the light emitting device 530 Can be applied.

That is, the phosphor may be excited by the light having the first light emitted from the light emitting device 530 to generate the second light. For example, when the light emitting element 530 is a blue light emitting diode and the phosphor is a yellow phosphor, the yellow phosphor may be excited by blue light to emit yellow light, and blue light and blue light emitted from the blue light emitting diode As the excited yellow light is mixed, the light emitting device package 500 can provide white light.

Similarly, when the light emitting element 530 is a green light emitting diode, the magenta phosphor or the blue and red phosphors are mixed, and when the light emitting element 530 is a red light emitting diode, the cyan phosphors or the blue and green phosphors are mixed For example.

Such a fluorescent material may be a known fluorescent material such as a YAG, TAG, sulfide, silicate, aluminate, nitride, carbide, nitridosilicate, borate, fluoride or phosphate.

The first and second lead frames 540 and 550 may be formed of a metal material such as titanium, copper, nickel, gold, chromium, tantalum, (Pt), tin (Sn), silver (Ag), phosphorus (P), aluminum (Al), indium (In), palladium (Pd), cobalt (Co), silicon (Si), germanium , Hafnium (Hf), ruthenium (Ru), and iron (Fe). Also, the first and second lead frames 540 and 550 may be formed to have a single layer or a multilayer structure, but the present invention is not limited thereto.

The first and second lead frames 540 and 550 are separated from each other and electrically separated from each other. The light emitting element 530 is mounted on the first and second lead frames 540 and 550 and the first and second lead frames 540 and 550 are in direct contact with the light emitting element 530, And may be electrically connected through a conductive material such as a conductive material. In addition, the light emitting device 530 may be electrically connected to the first and second lead frames 540 and 550 through wire bonding (not shown), but is not limited thereto. Accordingly, when power is supplied to the first and second lead frames 540 and 550, power may be applied to the light emitting device 530. Meanwhile, a plurality of lead frames (not shown) may be mounted in the body 510 and each lead frame (not shown) may be electrically connected to the light emitting device 530, but is not limited thereto.

The light emitting device according to the embodiment can be applied to an illumination system. The lighting system includes a structure in which a plurality of light emitting elements are arrayed and includes a display device shown in Figs. 7 and 8, a lighting device shown in Fig. 9, and may include a lighting lamp, a traffic light, a vehicle headlight, have.

7 is an exploded perspective view of a display device having a light emitting device according to an embodiment.

7, a display device 1000 according to an embodiment includes a light guide plate 1041, a light source module 1031 for providing light to the light guide plate 1041, and a reflection member 1022 An optical sheet 1051 on the light guide plate 1041 and a display panel 1061 on the optical sheet 1051 and the light guide plate 1041, the light source module 1031, and the reflection member 1022 And the bottom cover 1011. The bottom cover 1011, the reflective sheet 1022, the light guide plate 1041 and the optical sheet 1051 may be defined as a light unit 1050 .

The light guide plate 1041 serves to diffuse light into a surface light source. The light guide plate 1041 may be made of a transparent material, for example, acrylic resin such as polymethylmethacrylate (PET), polyethylene terephthalate (PET), polycarbonate (PC), cycloolefin copolymer (COC), and polyethylene naphtha late Resin. ≪ / RTI >

The light source module 1031 provides light to at least one side of the light guide plate 1041, and ultimately acts as a light source of the display device.

The light source module 1031 includes at least one light source module 1031 and may directly or indirectly provide light from one side of the light guide plate 1041. The light source module 1031 includes a substrate 1033 and a light emitting device 1035 according to the embodiment described above and the light emitting devices 1035 may be arrayed at a predetermined interval on the substrate 1033 .

The substrate 1033 may be a printed circuit board (PCB) including a circuit pattern (not shown). However, the substrate 1033 may include not only a general PCB, but also a metal core PCB (MCPCB), a flexible PCB (FPCB), and the like. When the light emitting element 1035 is mounted on the side surface of the bottom cover 1011 or on the heat radiation plate, the substrate 1033 can be removed. Here, a part of the heat radiating plate may be in contact with the upper surface of the bottom cover 1011.

The plurality of light emitting devices 1035 may be mounted on the substrate 1033 such that the light emitting surface is spaced apart from the light guiding plate 1041 by a predetermined distance. However, the present invention is not limited thereto. The light emitting device 1035 may directly or indirectly provide light to the light-incident portion, which is one surface of the light guide plate 1041, but the present invention is not limited thereto.

The reflective member 1022 may be disposed under the light guide plate 1041. The reflection member 1022 reflects the light incident on the lower surface of the light guide plate 1041 so as to face upward, thereby improving the brightness of the light unit 1050. The reflective member 1022 may be formed of, for example, PET, PC, or PVC resin, but is not limited thereto. The reflective member 1022 may be an upper surface of the bottom cover 1011, but is not limited thereto.

The bottom cover 1011 may house the light guide plate 1041, the light source module 1031, the reflective member 1022, and the like. To this end, the bottom cover 1011 may be provided with a housing portion 1012 having a box-like shape with an opened upper surface, but the present invention is not limited thereto. The bottom cover 1011 may be coupled to the top cover, but is not limited thereto.

The bottom cover 1011 may be formed of a metal material or a resin material, and may be manufactured using a process such as press molding or extrusion molding. In addition, the bottom cover 1011 may include a metal or a non-metal material having good thermal conductivity, but the present invention is not limited thereto.

The display panel 1061 is, for example, an LCD panel, including first and second transparent substrates facing each other, and a liquid crystal layer interposed between the first and second substrates. A polarizing plate may be attached to at least one surface of the display panel 1061, but the present invention is not limited thereto. The display panel 1061 displays information by light passing through the optical sheet 1051. Such a display device 1000 can be applied to various types of portable terminals, monitors of notebook computers, monitors of laptop computers, televisions, and the like.

The optical sheet 1051 is disposed between the display panel 1061 and the light guide plate 1041 and includes at least one light-transmitting sheet. The optical sheet 1051 may include at least one of a sheet such as a diffusion sheet, a horizontal and vertical prism sheet, and a brightness enhancement sheet. The diffusion sheet diffuses incident light, and the horizontal and / or vertical prism sheet condenses incident light into a display area. The brightness enhancing sheet improves the brightness by reusing the lost light. A protective sheet may be disposed on the display panel 1061, but the present invention is not limited thereto.

Here, the optical path of the light source module 1031 may include the light guide plate 1041 and the optical sheet 1051 as an optical member, but the invention is not limited thereto.

8 is a view showing a display device having a light emitting device according to an embodiment.

8, the display device 1100 includes a bottom cover 1152, a substrate 1120 on which the above-described light emitting device 1124 is arrayed, an optical member 1154, and a display panel 1155.

The substrate 1120 and the light emitting device 1124 may be defined as a light source module 1160. The bottom cover 1152, the at least one light source module 1160, and the optical member 1154 may be defined as a light unit 1150. The bottom cover 1152 may include a receiving portion 1153, but the present invention is not limited thereto. The light source module 1160 includes a substrate 1120 and a plurality of light emitting devices 1124 arranged on the substrate 1120.

Here, the optical member 1154 may include at least one of a lens, a light guide plate, a diffusion sheet, a horizontal and vertical prism sheet, and a brightness enhancement sheet. The light guide plate may be made of a PC material or a polymethyl methacrylate (PMMA) material, and the light guide plate may be removed. The diffusion sheet diffuses incident light, and the horizontal and vertical prism sheets condense incident light into a display area. The brightness enhancing sheet enhances brightness by reusing the lost light.

The optical member 1154 is disposed on the light source module 1160 and performs surface light source, diffusion, and light condensation of light emitted from the light source module 1160.

9 is an exploded perspective view of a lighting device having a light emitting device according to an embodiment.

9, the lighting apparatus according to the embodiment includes a cover 2100, a light source module 2200, a heat discharger 2400, a power supply unit 2600, an inner case 2700, and a socket 2800 . Further, the illumination device according to the embodiment may further include at least one of the member 2300 and the holder 2500. The light source module 2200 may include a light emitting device according to an embodiment of the present invention.

For example, the cover 2100 may have a shape of a bulb or a hemisphere, and may be provided in a shape in which the hollow is hollow and a part is opened. The cover 2100 may be optically coupled to the light source module 2200. For example, the cover 2100 may diffuse, scatter, or excite light provided from the light source module 2200. The cover 2100 may be a kind of optical member. The cover 2100 may be coupled to the heat discharging body 2400. The cover 2100 may have an engaging portion that engages with the heat discharging body 2400.

The inner surface of the cover 2100 may be coated with a milky white paint. Milky white paints may contain a diffusing agent to diffuse light. The surface roughness of the inner surface of the cover 2100 may be larger than the surface roughness of the outer surface of the cover 2100. This is for sufficiently diffusing and diffusing the light from the light source module 2200 and emitting it to the outside.

The cover 2100 may be made of glass, plastic, polypropylene (PP), polyethylene (PE), polycarbonate (PC), or the like. Here, polycarbonate is excellent in light resistance, heat resistance and strength. The cover 2100 may be transparent so that the light source module 2200 is visible from the outside, and may be opaque. The cover 2100 may be formed by blow molding.

The light source module 2200 may be disposed on one side of the heat discharging body 2400. Accordingly, heat from the light source module 2200 is conducted to the heat discharger 2400. The light source module 2200 may include a light emitting device 2210, a connection plate 2230, and a connector 2250.

The member 2300 is disposed on the upper surface of the heat discharging body 2400 and has guide grooves 2310 into which the plurality of light emitting elements 2210 and the connector 2250 are inserted. The guide groove 2310 corresponds to the substrate of the light emitting device 2210 and the connector 2250.

The surface of the member 2300 may be coated or coated with a light reflecting material. For example, the surface of the member 2300 may be coated or coated with a white paint. The member 2300 reflects the light reflected by the inner surface of the cover 2100 toward the cover 2100 in the direction toward the light source module 2200. Therefore, the light efficiency of the illumination device according to the embodiment can be improved.

The member 2300 may be made of an insulating material, for example. The connection plate 2230 of the light source module 2200 may include an electrically conductive material. Therefore, electrical contact can be made between the heat discharging body 2400 and the connecting plate 2230. The member 2300 may be formed of an insulating material to prevent an electrical short circuit between the connection plate 2230 and the heat discharging body 2400. The heat discharger 2400 receives heat from the light source module 2200 and heat from the power supply unit 2600 to dissipate heat.

The holder 2500 blocks the receiving groove 2719 of the insulating portion 2710 of the inner case 2700. Therefore, the power supply unit 2600 housed in the insulating portion 2710 of the inner case 2700 is sealed. The holder 2500 has a guide protrusion 2510. The guide protrusion 2510 may have a hole through which the protrusion 2610 of the power supply unit 2600 passes.

The power supply unit 2600 processes or converts an electrical signal provided from the outside and provides the electrical signal to the light source module 2200. The power supply unit 2600 is housed in the receiving groove 2719 of the inner case 2700 and is sealed inside the inner case 2700 by the holder 2500.

The power supply unit 2600 may include a protrusion 2610, a guide unit 2630, a base 2650, and a protrusion 2670.

The guide portion 2630 has a shape protruding outward from one side of the base 2650. The guide portion 2630 may be inserted into the holder 2500. A plurality of components may be disposed on one side of the base 2650. The plurality of components include, for example, a DC converter for converting AC power supplied from an external power source into DC power, a driving chip for controlling driving of the light source module 2200, an ESD (ElectroStatic discharge) protective device, and the like, but the present invention is not limited thereto.

The protrusion 2670 has a shape protruding outward from the other side of the base 2650. The protrusion 2670 is inserted into the connection portion 2750 of the inner case 2700 and receives an external electrical signal. For example, the protrusion 2670 may be equal to or smaller than the width of the connection portion 2750 of the inner case 2700. One end of each of the positive wire and the negative wire is electrically connected to the protrusion 2670 and the other end of the positive wire and the negative wire are electrically connected to the socket 2800.

The inner case 2700 may include a molding part together with the power supply part 2600. The molding part is a hardened portion of the molding liquid so that the power supply unit 2600 can be fixed inside the inner case 2700.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, It will be understood 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 (13)

Board;
A first conductive semiconductor layer on the substrate;
An active layer on the first conductive semiconductor layer; And
And a second conductive semiconductor layer on the active layer,
The first conductive semiconductor layer may include a first conductive semiconductor layer,
A second layer disposed on the first layer, and a third layer disposed on the second layer, wherein the first layer includes a plurality of concave depressions on the upper surface,
The first layer is doped with impurities,
The second layer is an undoped layer which is not doped with impurities,
And the third layer comprises InAlGaN. The method according to claim 1,
And the third layer has an In content of 2% to 5%. 3. The method of claim 2,
And the content of Al in the third layer is 6% to 10%. The method of claim 3,
And the third layer has a thickness of 2 nm to 20 nm. The method according to claim 1,
Wherein the first depressed portion has a hexagonal or wedge shape. 6. The method of claim 5,
Wherein the first recessed portion is vertically overlapped on a dislocation formed in the first layer. The method according to claim 6,
Wherein the second layer further comprises a second indentation formed at a position vertically overlapping the first indentation,
And the third layer includes a third indent formed at a position vertically overlapping the second indentation. 8. The method of claim 7,
And a strain relief layer disposed between the third layer and the active layer,
And the strain relief layer includes a fourth indentation formed at a position vertically overlapping the third indentation. 9. The method of claim 8,
And the active layer includes a fifth recessed portion formed at a position vertically overlapping the fourth recessed portion. 10. The method of claim 9,
And the size of the fourth indent is smaller than the size of the third indent. 10. The method of claim 9,
And the second conductive semiconductor layer is formed to fill the fifth indented portion. A light emitting device package comprising the light emitting device according to any one of claims 1 to 11. A lighting device comprising the light-emitting element according to any one of claims 1 to 11.

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