KR102145912B1 - Light emitting device and light emitting device package including the same - Google Patents

Abstract

The embodiment includes a substrate on which a plurality of patterns are formed; An undoped semiconductor layer disposed on the substrate and in contact with the pattern; An air void formed between the pattern and the undoped semiconductor layer; And a light emitting structure disposed on the undoped semiconductor layer and including a first conductivity type semiconductor layer, an active layer, and a second conductivity type semiconductor layer.

Description

Light-emitting device and light-emitting device package including the same {LIGHT EMITTING DEVICE AND LIGHT EMITTING DEVICE PACKAGE INCLUDING THE SAME}

The embodiment relates to a light emitting device and a light emitting device package including the same, and more particularly, to a light emitting device having improved light extraction efficiency.

Group 3-5 compound semiconductors such as GaN and AlGaN are widely used in optoelectronics and electronic devices due to their many advantages, such as having a wide and easily adjustable band gap energy.

In particular, light emitting devices such as Ligit Emitting Diodes and laser diodes using semiconductor materials of Group 3-5 or Group 2-6 compound are developed in thin film growth technology and device materials, such as red, green, blue and ultraviolet rays. Various colors can be implemented, and efficient white light can be realized by using fluorescent materials or by combining colors. Low power consumption, semi-permanent life, quick response speed, safety, and environment compared to conventional light sources such as fluorescent lamps and incandescent lamps. It has the advantage of affinity.

Therefore, a light-emitting diode backlight that replaces the cold cathode fluorescent lamp (CCFL) constituting the transmission module of the optical communication means, the backlight of the LCD (Liquid Crystal Display) display device, and white light that can replace fluorescent or incandescent bulb Applications are expanding to diode lighting devices, automobile headlights and traffic lights.

Conventional light emitting devices include an undoped semiconductor layer (un-GaN), a first conductivity type semiconductor layer (n-GaN), an active layer (MQW), and a second conductivity type semiconductor layer (p-) on a substrate made of sapphire or the like. A light emitting structure including GaN) may be formed, and a first electrode and a second electrode may be disposed on the first conductive type semiconductor layer and the second conductive type semiconductor layer, respectively.

The light emitting device emits light having energy determined by an energy band unique to a material constituting the active layer by meeting each other with electrons injected through the first conductivity type semiconductor layer and holes injected through the second conductivity type semiconductor layer. Light emitted from the active layer may vary depending on the composition of the material constituting the active layer, and may be blue light, ultraviolet (UV), deep ultraviolet (Deep UV), or light of a different wavelength range.

In order to improve the light extraction efficiency of the light emitting device, there are a method of forming irregularities by etching the surface of a light emitting structure, and a method of forming a pattern on the surface of a substrate.

1A and 1B are diagrams illustrating exemplary embodiments of a sapphire substrate PSS on which a pattern is formed.

When a pattern is formed on the sapphire substrate, the density of dislocations in the light emitting structure grown from the buffer layer or the undoped semiconductor layer can be reduced, and the light emitted from the active layer is reflected or refracted from the pattern of the sapphire substrate to improve light extraction efficiency. I can.

However, since light refraction between the undoped semiconductor layer and the sapphire substrate is insufficient, various efforts to improve the light extraction efficiency of the light emitting device have been continued.

The embodiment aims to improve light extraction efficiency of a light emitting device.

The embodiment includes a substrate on which a plurality of patterns are formed; An undoped semiconductor layer disposed on the substrate and in contact with the pattern; An air void formed between the pattern and the undoped semiconductor layer; And a light emitting structure disposed on the undoped semiconductor layer and including a first conductivity type semiconductor layer, an active layer, and a second conductivity type semiconductor layer.

Another embodiment is a substrate on which a plurality of patterns are formed; A first conductivity type semiconductor layer disposed on the substrate and in contact with the pattern; An air void formed between the pattern and the first conductivity type semiconductor layer; And an active layer and a second conductivity type semiconductor layer disposed on the first conductivity type semiconductor layer.

The air void may contact the side surface of the pattern.

The cross-sectional area of the pattern may be larger than the cross-sectional area of the area in contact with the substrate.

The length of the pattern in the transverse direction may be 1 micrometer to 3 micrometers.

The length of the air void in the horizontal direction may be 1/4 to 1/2 of the length of the pattern in the horizontal direction.

The height of the air void may be smaller than the height of the pattern.

The air void may have a length in a horizontal direction of a region in contact with the substrate greater than a length in a horizontal direction of another region.

The substrate and the pattern may be made of the same material.

The substrate may be made of any one of Al ₂ O ₃ , SiO ₂ , SiC, Si, GaAs, GaN, ZnO, GaP, InP, Ge, and Ga ₂ 0 ₃ .

Another embodiment is a body; A first lead frame and a second lead frame disposed on the body; The above-described light emitting device disposed on the body and electrically connected to the first lead frame and the second lead frame; And it provides a light emitting device package including a molding portion surrounding the light emitting device.

In the light emitting device according to the embodiment, an air void is formed under a pattern of a substrate, so that light emitted from the active layer is refracted and scattered in the air voids, thereby improving light extraction efficiency.

1A and 1B are views showing patterns formed on a substrate in a conventional light emitting device,
2A and 2B are diagrams showing the structure of the first embodiment of the light emitting device,
3 is a diagram showing the structure of a second embodiment of a light emitting device,
4A to 4E are views showing a method of manufacturing a pattern on a substrate of the light emitting device of FIG. 2A,
5 is a view showing an embodiment of a light emitting device package including a light emitting device,
6 is a view showing an embodiment of an image display device including a light emitting device,
7 is a view showing an embodiment of a lighting device including a light emitting device.

Hereinafter, embodiments of the present invention capable of realizing the above object will be described with reference to the accompanying drawings.

In the description of the embodiment according to the present invention, in the case where it is described as being formed in "on or under" of each element, the upper (upper) or lower (lower) (on or under) includes both elements in direct contact with each other or in which one or more other elements are indirectly formed between the two elements. In addition, when expressed as "on or under", it may include not only an upward direction but also a downward direction based on one element.

2A and 2B are diagrams showing the structure of the first embodiment of a light emitting device.

The light emitting device 100a according to the present embodiment includes a substrate 110 on which a plurality of patterns 115 are formed, an undoped semiconductor layer 130 disposed on the substrate and in contact with the pattern 115, and a pattern ( 115) and an air void 120 formed between the undoped semiconductor layer 130, and disposed on the undoped semiconductor layer 130, the first conductivity type semiconductor layer 142 and the active layer 144, and A light emitting structure 140 including a second conductivity type semiconductor layer 146 may be included.

The substrate 110 may be formed of a material suitable for growth of semiconductor materials or a carrier wafer, may be formed of a material having excellent thermal conductivity, and may include a conductive substrate or an insulating substrate. For example, at least one of sapphire (Al ₂ O ₃ ), SiO ₂ , SiC, Si, GaAs, GaN, ZnO, GaP, InP, Ge, Ga ₂ 0 ₃ may be used.

When the substrate 110 is formed of sapphire or the like, and the light emitting structure 220 including GaN or AlGaN is disposed on the substrate 110, the lattice mismatch between GaN or AlGaN and sapphire is very large. Since the difference in the coefficient of thermal expansion between them is also very large, dislocation, melt-back, crack, pit, and surface morphology defects that deteriorate crystallinity occur. Therefore, the buffer layer may be formed of AlN or the like or the undoped semiconductor layer 130 may be formed.

The pattern 115 may be formed of the same material as the substrate 110 and may be formed by partially etching the surface of the substrate 110. The pattern 115 may have a shape other than the shape shown in FIG. 2A, and each pattern 115 may have a different shape, but considering the etching process, the same or similar patterns 115 may be formed.

In the pattern 115, the size of the cross section of the central region may be larger than the size of the cross section of the region in contact with the substrate 110, and the central region of the pattern 115 geometrically does not mean the center of the pattern 115 It means the area between the top and bottom of 115.

And, since the size of the cross-section of the central region of the pattern 115 may be larger than the cross-section of the region in contact with the substrate 110, the length of one side of the pattern (d ₁ ) in the central region is It may be greater than the length (d ₂ ) of one side in the contacting area. Here, the length of one side (d ₁ , d ₂ ) is when the cross section in the horizontal direction of the pattern 115 is a polygon, and if the cross section is circular, it may be a diameter.

The air void 120 may be formed between the substrate 110 and the pattern 115. More specifically, the air void 120 is in contact with the side surface of the pattern 115 and the upper portion of the substrate 110 and the undoped semiconductor layer 130. Can be placed. And, as the pattern 115 is shown, the length (d ₂ ) of the region in contact with the substrate 110 is shorter than the length (d ₁ ) of the central region, so the lower portion of the pattern 115 is inwardly recessed. The air void 120 may be inserted and disposed in a region in which the pattern 115 is recessed.

The length in the horizontal direction of the pattern 115 may be 1 micrometer to 3 micrometers, and the length in the horizontal direction may be lengths of one side (d ₁ , d ₂ ) in FIG. 2A. If the length of the pattern 115 in the horizontal direction is too small, light extraction may not be sufficiently improved by light scattering. If it is too large, the scattered light may be uneven and traces due to spots or other light scattering may appear.

The length d ₃ of the air void 120 in the horizontal direction may be 1/4 to 1/2 of the length in the horizontal direction of the pattern. If the length (d ₃ ) in the horizontal direction of the air void 120 is too small, the improvement of light extraction by light scattering may not be sufficient, and if it is too large, the lower region of the pattern 115 is not stably fixed to the substrate 110. It may not be possible.

The height (h ₂ ) of the air void 120 may be smaller than the height (h ₁ ) of the pattern 115, since the air void 120 is inserted and disposed in the area where the pattern 115 is recessed from the bottom to the inside. It is a structure that follows. In addition, the height h ₂ of the air void 120 and the length d _{3 in the} horizontal direction may be nanoscale.

The air void 120 may have a horizontal length d ₃ of a region in contact with the substrate 110 that is greater than the horizontal length of another region. In the structure shown in FIG. 2A, the horizontal length of the air void 120 The length of the direction is largest in a region in contact with the substrate 110 and may decrease toward the light emitting structure 140.

2B is a cross-sectional view of FIG. 2A in the transverse direction (horizontal direction) at an intermediate height of the air void 120, and the air void 120 surrounds the circumference of the pattern 115 in the form of a ring, and the air void The circumference of 120 is surrounded by an undoped semiconductor layer 130.

The undoped semiconductor layer 130 may be disposed in contact with the substrate 110, the pattern 115 and the air void 120, but may be omitted in some cases, and the same is the same in the embodiment of FIG. 3. Even if the undoped semiconductor layer 130 is grown on the pattern 120, the refractive index is different from that of air, so light scattering may occur between the air void 120 and the undoped semiconductor layer 130.

The light emitting structure 140 includes a first conductivity type semiconductor layer 142, an active layer 144 and a second conductivity type semiconductor layer 146.

The first conductivity type semiconductor layer 142 may be implemented as a compound semiconductor such as Group III-V or Group II-VI, and may be a semiconductor layer of a first conductivity type by doping with a first conductivity type dopant. The first conductivity type semiconductor layer 142 is a semiconductor material having a composition formula of Al _x In _y Ga _(1-xy) N (0≤x≤1, 0≤y≤1, 0≤x+y≤1), AlGaN , GaN, InAlGaN, AlGaAs, GaP, GaAs, GaAsP, AlGaInP may be formed of any one or more.

When the first conductivity-type semiconductor layer 142 is an n-type semiconductor layer, the first conductivity-type dopant may include an n-type dopant such as Si, Ge, Sn, Se, and Te. The first conductivity type semiconductor layer 142 may be formed as a single layer or multiple layers, but is not limited thereto.

The active layer 144 is disposed on the upper surface of the first conductivity type semiconductor layer 142, and has a single well structure, a multi-well structure, a single quantum well structure, and a multi-quantum well (MQW) structure. , It may include any one of a quantum dot structure or a quantum wire structure.

The active layer 144 is a well layer and a barrier layer, such as AlGaN/AlGaN, InGaN/GaN, InGaN/InGaN, AlGaN/GaN, InAlGaN/GaN, GaAs (InGaAs), using a compound semiconductor material of group III-V element. /AlGaAs, GaP (InGaP) / AlGaP may be formed in any one or more pair structure, but is not limited thereto. The well layer may be formed of a material having an energy band gap smaller than that of the barrier layer.

The second conductivity type semiconductor layer 146 may be formed of a semiconductor compound on the surface of the active layer 144. The second conductivity-type semiconductor layer 146 may be implemented as a compound semiconductor such as Group III-V or Group II-VI, and may be doped with a second conductivity-type dopant. The second conductivity type semiconductor layer 146 is, for example, 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), AlGaN , GaN AlInN, AlGaAs, GaP, GaAs, GaAsP, AlGaInP may be formed of any one or more, for example, the second conductivity type semiconductor layer 146 may be formed of Al _x Ga _(1-x) N.

The second conductivity type semiconductor layer 146 may be a second conductivity type semiconductor layer doped with a second conductivity type dopant. When the second conductivity type semiconductor layer 146 is a p type semiconductor layer, the second conductivity type dopant is Mg , Zn, Ca, Sr, Ba, etc. may be a p-type dopant. The second conductivity type semiconductor layer 146 may be formed as a single layer or multiple layers, but is not limited thereto.

Although not shown, an electron blocking layer may be disposed between the active layer 144 and the second conductivity type semiconductor layer 146. The electron blocking layer may have a superlattice structure, for example, AlGaN doped with a second conductivity type dopant may be disposed, and GaN having a different composition ratio of aluminum is formed as a layer. A plurality may be arranged alternately with each other.

Although not shown, a portion of the active layer 144 and the first conductivity-type semiconductor layer 142 from the second conductivity-type semiconductor layer 146 is mesa-etched in a partial region of the light emitting structure 140 to form a first conductivity-type semiconductor layer. The surface of 142 is exposed.

A first electrode and a second electrode are disposed on the exposed surface of the first conductivity-type semiconductor layer 142 and on the second conductivity-type semiconductor layer 146, respectively, and the first and second electrodes are aluminum (Al) and titanium. (Ti), chromium (Cr), nickel (Ni), copper (Cu), may be formed in a single-layer or multi-layered structure including at least one of gold (Au), each may be connected to a wire (not shown).

In addition, the surface of the second conductivity-type semiconductor layer 146 may be formed with irregularities to improve light extraction efficiency, and a passivation layer may be formed around the light emitting structure 140, and the passivation layer is made of an insulating material. I can. The insulating material may be made of a non-conductive oxide or nitride, and more specifically, a silicon oxide (SiO ₂ ) layer, an oxide nitride layer, and an aluminum oxide layer.

3 is a diagram showing the structure of a second embodiment of a light emitting device.

The light emitting device 100b according to the present embodiment is similar to the light emitting device 100b shown in FIG. 2A, but the shape of the pattern 115 is different. That is, the vertical cross section of the pattern 115 in FIG. 2A may be a shape in which both sides of the lower part are etched in a triangle, and in FIG. 3, the cross section in the vertical direction of the pattern 115 is a shape in which both sides of the lower part are etched from a circle. May be, and air voids 120 may be disposed in each etched area.

In FIG. 3, the size or positional relationship between the air void 120 and the pattern 115 may be the same as that of FIG. 2A.

4A to 4E are views illustrating a method of manufacturing a pattern on a substrate of the light emitting device of FIG. 2A.

First, as shown in FIG. 4A, a pattern 115 is formed by etching the surface of the substrate 110, and the surface of the substrate 110 may be etched by a dry etching method.

A photoresist 200 is applied around the etched pattern 115 as shown in FIG. 4B, and the photoresist 200 is etched as shown in FIG. 4C by a wet etching method. The lower surface of may be further etched so that the side surface and the lower surface form an obtuse angle, and at this time, a part of the pattern 115 may be exposed in the'a' area.

Here, after the photoresist is applied, the above-described etching may be performed by less exposing the lower part in the exposure process, and the exposure may be controlled by a method such as adjusting the focus.

In addition, as shown in FIG. 4C, the lower portion of the commercial market exposed by removing the photoresist 200 may be etched by a dry etching method. In this case, the pattern exposed in the area'a' in FIG. 4C is removed, and thus'b' As shown in the 'area, the contours of the photoresist 200 and the pattern 115 may match.

And, when the photoresist 200 is removed, the pattern 115 shown in FIG. 4E is completed.

Although one pattern 115 is shown on the substrate 110 in FIGS. 4A to 4E, a plurality of patterns 115 may be formed in the entire area of the substrate 110. In addition, when the undoped semiconductor layer is grown on the structure of FIG. 4E, the undoped semiconductor layer may not be grown in the region'b' described above under the pattern 115 and air voids may be formed. That is, the undoped semiconductor layer may be mainly vertically grown initially and then horizontally grown.

The table below compares the light emitting device according to the embodiment of FIG. 2A with a conventional comparative example. It can be seen that the light extraction efficiency of the light emitting device according to the embodiment in which the air void is formed is improved by about 5.8% when the same power is input.

Input power efficiency Absolute value Relative value Comparative example One 0.836 0.94 Example One 0.885 One

5 is a view showing an embodiment of a light emitting device package including a light emitting device.

The light emitting device package 400 according to the embodiment includes a body 410 including a cavity, a first lead frame 421 and a second lead frame 422 installed on the body 410, and the body The light emitting device 200a according to the above-described embodiments installed in the 410 and electrically connected to the first lead frame 421 and the second lead frame 422, and a molding part 470 formed in the cavity Includes.

The body 410 may be formed of a silicon material, a synthetic resin material, or a metal material. When the body 410 is made of a conductive material such as a metal material, although not shown, an insulating layer is coated on the surface of the body 410 to prevent an electrical short between the first and second lead frames 421 and 422. I can.

The first lead frame 421 and the second lead frame 422 are electrically separated from each other, and supply current to the light emitting device 200a. In addition, the first lead frame 421 and the second lead frame 422 may reflect light generated from the light emitting device 200a to increase light efficiency, and transfer heat generated from the light emitting device 200a to the outside. It can also be discharged.

The light emitting device 200a may be a light emitting device according to the above-described embodiments.

The light emitting device 200a may be fixed to the first lead frame 421 with a conductive paste (not shown) or the like, and the electrode 430 may be bonded to the second lead frame with a wire 450.

The molding part 470 may surround and protect the light emitting device 200a. In addition, a phosphor 480 may be included on the molding part 470. In this structure, since the phosphor 480 is distributed, the wavelength of light emitted from the light emitting device 200a can be converted in the entire area of the light emitting device package 400 to which light is emitted.

The light emitting device package 400 may be mounted as one or a plurality of light emitting devices according to the above-described embodiments, but is not limited thereto.

Hereinafter, an image display device and a lighting device will be described as an embodiment of a lighting system in which the above-described light emitting device package is disposed.

6 is a diagram showing an embodiment of an image display device in which a light emitting device is disposed.

As shown, the image display device 500 according to the present embodiment includes a light source module, a reflector 520 on the bottom cover 510, and light emitted from the light source module disposed in front of the reflector 520. The first prism sheet 550 and the second prism sheet 560 and the second prism sheet 560 are disposed in front of the light guide plate 540 to guide the image display device in front of the light guide plate 540. It includes a panel 570 disposed in front and a color filter 580 disposed in the entirety of the panel 570.

The light source module includes a light emitting device package 535 on the circuit board 530. Here, the circuit board 530 may be a PCB or the like, and the light emitting device of the light emitting device package 535 is as described above.

The bottom cover 510 may accommodate components in the image display device 500. The reflector 520 may be provided as a separate component as shown in this drawing, or may be provided in a form coated with a material having high reflectivity on the rear surface of the light guide plate 540 or the front surface of the bottom cover 510.

The reflector 520 may use a material that has high reflectivity and can be used in an ultra-thin type, and may use PolyEthylene Terephtalate (PET).

The light guide plate 540 scatters light emitted from the light emitting device package module so that the light is uniformly distributed over the entire screen area of the liquid crystal display. Accordingly, the light guide plate 530 is made of a material having a good refractive index and transmittance, and may be formed of polymethylmethacrylate (PMMA), polycarbonate (PC), or polyethylene (PolyEthylene; PE). In addition, if the light guide plate 540 is omitted, an air guide type display device may be implemented.

The first prism sheet 550 is formed of a light-transmitting and elastic polymer material on one surface of the support film, and the polymer may have a prism layer in which a plurality of three-dimensional structures are repeatedly formed. Here, the plurality of patterns may be repeatedly provided in a stripe type with floors and valleys as shown.

In the second prism sheet 560, a direction of a floor and a valley on one side of the support film may be perpendicular to a direction of a floor and a valley on one side of the support film in the first prism sheet 550. This is to evenly distribute the light transmitted from the light source module and the reflective sheet in all directions of the panel 570.

In this embodiment, the first prism sheet 550 and the second prism sheet 560 form an optical sheet, and the optical sheet is formed of a different combination, for example, a micro lens array, or a diffusion sheet and a micro lens array. It may be made of a combination or a combination of a single prism sheet and a micro lens array.

The panel 570 may include a liquid crystal display. In addition to the liquid crystal display panel 560, other types of display devices that require a light source may be provided.

The panel 570 is in a state in which a liquid crystal is placed between the glass bodies and polarizing plates are placed on both glass bodies in order to utilize the polarization of light. Here, the liquid crystal has an intermediate characteristic between a liquid and a solid, and the liquid crystal, which is an organic molecule having fluidity like a liquid, has a state that is regularly arranged like a crystal, and the molecular arrangement is changed by an external electric field. Display an image.

A liquid crystal display panel used in a display device is an active matrix type, and uses a transistor as a switch for controlling a voltage supplied to each pixel.

A color filter 580 is provided on the front surface of the panel 570 to transmit light projected from the panel 570 and transmit only red, green, and blue light for each pixel, so that an image can be expressed.

7 is a diagram showing an embodiment of a lighting device in which a light emitting device is disposed.

The lighting apparatus according to the present embodiment may include a cover 1100, a light source module 1200, a radiator 1400, a power supply unit 1600, an inner case 1700, and a socket 1800. In addition, the lighting apparatus according to the embodiment may further include one or more of the member 1300 and the holder 1500, and the light source module 1200 may include a light emitting device package according to the above-described embodiments. .

The cover 1100 has a shape of a bulb or a hemisphere, is hollow, and may be provided in an open shape. The cover 1100 may be optically coupled to the light source module 1200. For example, the cover 1100 may diffuse, scatter, or excite light provided from the light source module 1200. The cover 1100 may be a kind of optical member. The cover 1100 may be coupled to the radiator 1400. The cover 1100 may have a coupling portion coupled to the radiator 1400.

A milky white paint may be coated on the inner surface of the cover 1100. The milky white paint may include a diffuser that diffuses light. The surface roughness of the inner surface of the cover 1100 may be greater than the surface roughness of the outer surface of the cover 1100. This is to sufficiently scatter and diffuse light from the light source module 1200 to emit it to the outside.

The material of the cover 1100 may be glass, plastic, polypropylene (PP), polyethylene (PE), polycarbonate (PC), or the like. Here, polycarbonate is excellent in light resistance, heat resistance, and strength. The cover 1100 may be transparent so that the light source module 1200 is visible from the outside, or may be opaque. The cover 1100 may be formed through blow molding.

The light source module 1200 may be disposed on one surface of the radiator 1400. Accordingly, heat from the light source module 1200 is conducted to the radiator 1400. The light source module 1200 may include a light emitting device package 1210, a connection plate 1230, and a connector 1250.

The member 1300 is disposed on an upper surface of the radiator 1400 and has guide grooves 1310 into which a plurality of light emitting device packages 1210 and a connector 1250 are inserted. The guide groove 1310 corresponds to the substrate and the connector 1250 of the light emitting device package 1210.

The surface of the member 1300 may be coated or coated with a light reflective material. For example, the surface of the member 1300 may be coated or coated with a white paint. The member 1300 reflects light reflected on the inner surface of the cover 1100 and returning toward the light source module 1200 toward the cover 1100. Therefore, it is possible to improve the light efficiency of the lighting device according to the embodiment.

The member 1300 may be made of an insulating material, for example. The connection plate 1230 of the light source module 1200 may include an electrically conductive material. Accordingly, electrical contact may be made between the radiator 1400 and the connection plate 1230. The member 1300 may be formed of an insulating material to block an electrical short between the connection plate 1230 and the radiator 1400. The radiator 1400 receives heat from the light source module 1200 and heat from the power supply unit 1600 to radiate heat.

The holder 1500 blocks the receiving groove 1719 of the insulating part 1710 of the inner case 1700. Accordingly, the power supply unit 1600 accommodated in the insulating unit 1710 of the inner case 1700 is sealed. The holder 1500 has a guide protrusion 1510. The guide protrusion 1510 has a hole through which the protrusion 1610 of the power supply unit 1600 passes.

The power supply unit 1600 processes or converts an electrical signal provided from the outside and provides it to the light source module 1200. The power supply unit 1600 is accommodated in the storage groove 1919 of the inner case 1700 and is sealed inside the inner case 1700 by the holder 1500. The power supply unit 1600 may include a protrusion 1610, a guide unit 1630, a base 1650, and an extension 1670.

The guide part 1630 has a shape protruding outward from one side of the base 1650. The guide part 1630 may be inserted into the holder 1500. A number of parts may be disposed on one surface of the base 1650. A number of components include, for example, a DC converter that converts AC power provided from an external power source to DC power, a driving chip that controls the driving of the light source module 1200, and an ESD for protecting the light source module 1200. (ElectroStatic discharge) may include a protection element, but is not limited thereto.

The extension part 1670 has a shape protruding outward from the other side of the base 1650. The extension part 1670 is inserted into the connection part 1750 of the inner case 1700 and receives an electrical signal from the outside. For example, the extension part 1670 may be provided equal to or smaller than the width of the connection part 1750 of the inner case 1700. Each end of the "+ wire" and "- wire" may be electrically connected to the extension part 1670, and the other end of the "+ wire" and "- wire" may be electrically connected to the socket 1800. .

The inner case 1700 may include a molding unit together with the power supply unit 1600 therein. The molding part is a part in which the molding liquid is solidified, and allows the power supply part 1600 to be fixed inside the inner case 1700.

The embodiments have been described above, but these are only examples and do not limit the present invention, and those of ordinary skill in the art to which the present invention belongs are not illustrated above within the scope not departing from the essential characteristics of the present embodiment. It will be seen that various modifications and applications are possible. For example, each component specifically shown in the embodiment can be modified and implemented. And differences related to such modifications and applications should be construed as being included in the scope of the present invention defined in the appended claims.

100a, 100b, 200a: light emitting element 110: substrate
115: pattern 120: air void
130: undoped bar conductor layer 140: light emitting structure
142: first conductivity type semiconductor layer 144: active layer
146: second conductivity type semiconductor layer 400: light emitting device package
410: body 421: first lead frame
422: second lead frame 450: wire
470: molding part 480: phosphor
500: image display device

Claims (11)

A substrate on which a plurality of patterns are formed;
An undoped semiconductor layer disposed on the substrate and in contact with the pattern;
An air void formed between the pattern and the undoped semiconductor layer; And
It is disposed on the undoped semiconductor layer and includes a light emitting structure including a first conductivity type semiconductor layer, an active layer, and a second conductivity type semiconductor layer,
The length in the horizontal direction of the pattern is 1 micrometer to 3 micrometers, the length in the horizontal direction of the air void is 1/4 to 1/2 of the length in the horizontal direction of the pattern,
The width of the pattern in the horizontal direction increases from the bottom surface of the undoped semiconductor layer to a first point, and from the first point to a second point between the bottom surface of the undoped semiconductor layer and the bottom surface of the light emitting structure. Decrease,
The air voids are disposed only at a height between the bottom surface of the undoped semiconductor layer and the first point in a vertical direction,
For one pattern, the air voids are disposed only in an inner region of the maximum width of the pattern in the horizontal direction,
The light emitting device in which the undoped semiconductor layer is disposed between adjacent patterns and between the air voids disposed in each of the adjacent patterns. delete delete delete delete delete delete The method of claim 1,
With respect to the one pattern, the light emitting device in which the undoped semiconductor layer is disposed outside the air void. The method of claim 1,
The substrate and the pattern are made of the same material. delete delete

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