KR102087937B1 - Light emitting device - Google Patents

Abstract

The light emitting device of the embodiment includes a submount, a light emitting structure on the submount, and the light emitting structure includes a substrate and a first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer under the substrate, and is disposed below the light emitting structure. First and second metal layers disposed on the sub-mount and spaced apart from each other, at least one first bump portion disposed between a portion of the first conductive semiconductor layer exposed by mesa etching and the first metal layer; At least one second bump portion disposed between the conductive semiconductor layer and the second metal layer and electrically separated from at least one of the other portion of the first conductive semiconductor layer exposed by mesa etching or the active layer exposed by mesa etching. And oppose and oppose and include a first reflective layer disposed over the submount.

Description

Light emitting device

An embodiment relates to a light emitting device.

Based on the development of gallium nitride (GaN) metal organic chemical vapor deposition and molecular beam growth, red, green, and blue light emitting diodes (LEDs) capable of high brightness and white light have been developed.

These LEDs do not contain environmentally harmful substances such as mercury (Hg) used in existing lighting equipment such as incandescent lamps and fluorescent lamps, so they have excellent eco-friendliness and have advantages such as long life and low power consumption. It is replacing. A key competitive factor for these LED devices is their high brightness and high brightness by high efficiency chip and packaging technology.

In order to achieve high brightness, it is important to increase light extraction efficiency. Flip-chip structure, surface texturing, patterned sapphire substrate (PSS), photonic crystal technology, and anti-reflection film to improve light extraction efficiency Various methods using the reflection layer structure have been studied.

Meanwhile, in the case of an ultraviolet light emitting device having a conventional flip chip structure and emitting ultraviolet light, light does not escape the light emitting structure, and after escaping in the sub-mount direction, is absorbed by the bump part and converted into heat, thereby reducing the amount of light. There is.

The embodiment provides a light emitting device having improved light extraction efficiency.

The light emitting device of the embodiment includes a sub mount; A light emitting structure on the submount; The light emitting structure is a substrate; And first and second metal layers under the substrate, the first conductive semiconductor layer, the active layer, and the second conductive semiconductor layer, disposed under the light emitting structure and spaced apart from each other on the sub-mount. At least one first bump portion disposed between a portion of the first conductivity-type semiconductor layer exposed by mesa etching and the first metal layer; At least one second bump part disposed between the second conductive semiconductor layer and the second metal layer; And a first reflective layer electrically separated from and facing at least one of the other portion of the first conductivity-type semiconductor layer exposed by the mesa etching or the active layer exposed by the mesa etching, and disposed on the sub-mount.

The area ratio of the first reflective layer of the entire upper surface of the sub-mount may be 50% to 70%.

The second width of the first reflective layer may be greater than the first width of the other portion of the first conductive semiconductor layer.

The first reflecting layer may include a first reflecting part facing the other part of the first conductive semiconductor layer; And a second reflecting portion adjacent to the first reflecting portion and not facing the other portion of the first conductivity type semiconductor layer.

The third width of the first reflector may be smaller than the fourth width of the second reflector.

The light emitting device may include: a first electrode disposed between the at least one first bump part and a portion of the first conductive semiconductor layer; And a second electrode disposed between the at least one second bump part and the second conductive semiconductor layer.

The first reflective layer may further include a third reflector facing at least one of the second electrode and the second conductive semiconductor layer.

The first reflector may include a first-first reflector facing the first electrode disposed under the other portion of the first conductive semiconductor layer; And a 1-2 reflective part facing the other part of the first conductive semiconductor layer.

A surface of the other portion of the first conductive semiconductor layer facing the first reflective layer may have roughness.

The first length of the first reflective layer may be longer than the second length of the light emitting structure.

The light emitting device may further include a second reflecting layer disposed under the other portion of the first conductivity type semiconductor layer facing the first reflecting layer. The second reflective layer may be disposed adjacent to the first electrode.

The width of the first reflective layer may be 10 μm to 1000 μm.

The surface of the active layer facing the first reflective layer may have roughness.

In the light emitting device according to the embodiment, the first reflective layer is disposed on a portion of the mesa-etched first conductivity-type semiconductor layer or a portion opposite to the mesa-etched active layer on the sub-mount, so that the light-emitting device does not escape upward and is reflected. Can improve the light extraction efficiency by reflecting the light escaping toward the sub-mount,

Roughness may be formed on a surface of the first conductivity-type semiconductor layer or the active layer opposite to the first reflective layer to help the reflected light escape to the lower side of the light emitting structure without escaping upwardly of the light emitting structure. By allowing more light to be reflected in the reflective layer, the light extraction efficiency can be further improved.

1 is a plan view of a light emitting device according to an embodiment.
FIG. 2 is a cross-sectional view taken along the line AA ′ of FIG. 1.
3 shows a cross-sectional view of a light emitting device of another embodiment.
4 is a sectional view of a light emitting device according to still another embodiment;
5 is a graph for explaining the brightness enhancement of the light emitting device according to the embodiment.
6A to 6E are cross-sectional views illustrating a method of manufacturing the light emitting device according to the embodiment.
7 is a cross-sectional view of a light emitting device package according to an embodiment.
8 illustrates a display device including a light emitting device package according to an exemplary embodiment.
9 illustrates a head lamp including a light emitting device package according to an embodiment.
10 illustrates a lighting device including a light emitting device according to the embodiment.

Hereinafter, the present invention will be described in detail with reference to examples, and detailed description will be made with reference to the accompanying drawings to help understanding of the present invention. However, embodiments according to the present invention may be modified in many different forms, and the scope of the present invention should not be construed as being limited to the embodiments described below. Embodiments of the present invention are provided to more completely explain the present invention to those skilled in the art.

In the description of the embodiment according to the present invention, when described as being formed on the "on" or "on" (under) of each element, the upper (up) or the lower (down) (on or under) includes both the two elements are in direct contact with each other (directly) or one or more other elements are formed indirectly between the two elements (indirectly). In addition, when expressed as "up" or "on (under)", it may include the meaning of the downward direction as well as the upward direction based on one element.

Furthermore, the relational terms used below, such as "first" and "second," "upper" and "lower" and the like, do not necessarily require or imply any physical or logical relationship or order between such entities or elements. It may be used only to distinguish one entity or element from another entity or element.

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

1 is a plan view of a light emitting device 100A according to an embodiment, and FIG. 2 is a cross-sectional view taken along the line AA ′ of FIG. 1. In FIG. 1, the first and second bump parts 132 and 134 and the first and second electrodes 142 and 144 are not visible by the light emitting structure 150A, but are shown for better understanding of the present embodiment.

1 and 2, the light emitting device 100A according to the embodiment includes a sub-mount 110, first and second metal layers 122 and 124, and at least one first bump part 132. And at least one second bump part 134, first and second electrodes 142 and 144, a light emitting structure 150A, a substrate 160, and a first reflective layer 170.

The light emitting device 100A includes an LED using a plurality of compound semiconductor layers, and the LED includes colored LEDs, ultraviolet (UltraViolet) LEDs, deep ultraviolet LEDs, or non-polarized LEDs that emit light such as blue, green, or red light. Can be. The emission light of the LED may be implemented using various semiconductors, but is not limited thereto.

The substrate 160 is light transmissive so that light emitted from the active layer 154A is emitted through the substrate 160. For example, the substrate 160 may be formed of at least one of sapphire (Al ₂ O ₃ ), SiC, GaAs, GaN, ZnO, Si, GaP, InP, Ge, but is not limited thereto. In addition, the substrate 160 may have a mechanical strength to be well separated into separate chips through a scribing process and a breaking process without causing warping of the entire nitride semiconductor.

A buffer layer (not shown) may be further disposed between the substrate 160 and the light emitting structure 150A. The buffer layer serves to improve lattice matching between the substrate 160 and the light emitting structure 150A. For example, the buffer layer may include, but is not limited to, AlN or undoped nitride. The buffer layer may be omitted as illustrated in FIGS. 1 and 2 depending on the type of the substrate 160 and the type of the light emitting structure 150A.

The light emitting structure 150A includes a first conductive semiconductor layer 152A, an active layer 154A, and a second conductive semiconductor layer 156 sequentially stacked below the substrate 160.

The first conductivity type semiconductor layer 152A is disposed under the substrate 160. That is, the first conductivity type semiconductor layer 152A may be disposed between the substrate 160 and the active layer 154A and may be formed of a semiconductor compound. It may be implemented as a compound semiconductor, such as III-V group, II-VI group, and the first conductivity type dopant may be doped. For example, the first conductivity type semiconductor layer 152A has a composition formula of Al _x In _y Ga _(1-xy) N (0 ≦ x ≦ 1, 0 ≦ y ≦ 1, 0 ≦ x + y ≦ 1). The semiconductor material may be formed of any one or more of InAlGaN, AlGaAs, GaP, GaAs, GaAsP, and AlGaInP. When the first conductive semiconductor layer 152A is an n-type semiconductor layer, the first conductive dopant may include an n-type dopant such as Si, Ge, Sn, Se, Te, or the like. The first conductivity type semiconductor layer 152A may be formed as a single layer or a multilayer, but is not limited thereto. If the light emitting device 100A is an ultraviolet (UV) light or a non-polarization light emitting device, the first conductive semiconductor layer 152A may include at least one of InAlGaN and AlGaN. When the first conductivity type semiconductor layer 152A is made of AlGaN, the Al content may be, for example, 50%.

The active layer 154A is disposed under the first conductivity type semiconductor layer 152A and may emit ultraviolet light, particularly deep ultraviolet light, in the wavelength range of 200 nm to 405 nm. The active layer 154A is disposed between the first conductive semiconductor layer 152A and the second conductive semiconductor layer 156 and has a single well structure, a multi well structure, a single quantum well structure, and a multi quantum well (MQW). Well) structure, may include any one of the quantum dot structure or quantum line structure. The active layer 154A is formed of a well layer and a barrier layer, for example, InGaN / GaN, InGaN / InGaN, GaN / AlGaN, InAlGaN / GaN, GaAs (InGaAs), / AlGaAs, using a compound semiconductor material of group III-V elements. One or more pairs of GaP (InGaP) / AlGaP may be formed, but is not limited thereto. The well layer may be formed of a material having an energy band gap smaller than the energy band gap of the barrier layer.

The second conductivity type semiconductor layer 156 is disposed under the active layer 154A. The second conductivity type semiconductor layer 156 may be formed of a semiconductor compound. The second conductive semiconductor layer 156 may be formed of a compound semiconductor such as a group III-V group or a group II-VI, and may be doped with a second conductive dopant. For example, In _x Al _y Ga _{1 -x- y} N semiconductor materials having a composition formula of (0≤x≤1, 0≤y≤1, 0≤x + y≤1 ) or AlInN, AlGaAs, GaP, GaAs, GaAsP , AlGaInP may be formed of any one or more. When the second conductive semiconductor layer 156 is a p-type semiconductor layer, the second conductive dopant may be a p-type dopant such as Mg, Zn, Ca, Sr, or Ba. The second conductivity-type semiconductor layer 156 may be formed as a single layer or a multilayer, but is not limited thereto. If the light emitting device 100A is an ultraviolet (UV) light or a non-polarization light emitting device, the second conductivity-type semiconductor layer 156 may include at least one of InAlGaN and AlGaN.

In addition, an electron blocking layer (EBL) (not shown) may be selectively disposed between the active layer 154A and the second conductive semiconductor layer 156. The electron blocking layer may be formed of a semiconductor material having a larger energy band gap than the second conductivity type semiconductor layer 156. When the electron blocking layer EBL has a larger energy band gap than the second conductivity type semiconductor layer 156, electrons provided from the first conductivity type semiconductor layer 152A are not recombined in the active layer 154A of the MQW structure. It is possible to effectively prevent the second conductive semiconductor layer 156 from overflowing. The electron blocking layer may include aluminum (Al) having a higher content than the barrier layer of the active layer 154A.

Meanwhile, the light emitting structure 150A is positioned on the sub mount 110 in a flip manner. For example, the sub-mount 110 may be formed of a semiconductor substrate such as AlN, BN, silicon carbide (SiC), GaN, GaAs, Si, or the like, but may be formed of a semiconductor material having thermal properties. For example, the submount 110 may have a thickness of 350 μm to 400 μm.

If the submount 110 is made of Si, an insulating layer (not shown) may be further disposed between at least one of the first and second metal layers 122 and 124 and the submount 110. Here, the insulating layer serves to electrically separate the first and second metal layers from each other, and may be made of an insulating material such as SiO ₂ .

The first and second metal layers 122 and 124 are spaced apart from each other on the submount 110. Each of the first and second metal layers 122 and 124 may include a metallic material. For example, each of the first and second metal layers 122, 124 may comprise at least one of Ag, Ni, Al, Rh, Pd, Ir, Ru, Mg, Zn, Pt, Au, or Hf or an optional combination thereof. It may be formed of a metal or alloy containing. Alternatively, each of the first and second metal layers 122 and 124 may be formed in a multilayer using a metal or an alloy and a light-transmitting conductive material such as ITO, IZO, IZTO, IAZO, IGZO, IGTO, AZO, or ATO. For example, it may be laminated with IZO / Ni, AZO / Ag, IZO / Ag / Ni, AZO / Ag / Ni, Ag / Cu, Ag / Pd / Cu, and the like.

The at least one first bump part 132 is disposed between the portion 152-1 and the first metal layer 122 of the first conductivity type semiconductor layer 152A exposed by mesa etching. 152-1, 122 are electrically connected to each other. At least one second bump part 134 is disposed between the second conductivity type semiconductor layer 156 and the second metal layer 124 to electrically connect them 156 and 124 with each other.

Although not shown, a first upper bump metal layer (not shown) is further disposed between the first electrode 142 and the first bump part 132, and the first metal layer 122 and the first bump part 132 are disposed. A first lower bump metal layer (not shown) may be further disposed therebetween. Here, the first upper bump metal layer and the first lower bump metal layer serve to indicate a position where the first bump part 132 is to be located. Similarly, a second upper bump metal layer (not shown) is further disposed between the second electrode 144 and the second bump part 134, and a second between the second metal layer 124 and the second bump part 134. A lower bump metal layer (not shown) may be further disposed. Here, the second upper bump metal layer and the second lower bump metal layer serve to indicate a position where the second bump part 134 is to be located.

1 and 2, each of the first and second bump portions 132 and 134 is illustrated as one person, but embodiments are not limited thereto. That is, a plurality of first bump portions 132 may be disposed between a portion of the mesa etched first conductive semiconductor layer 152A and the first metal layer 122, and the second conductive semiconductor layer 154A A plurality of second bumps 134 may be disposed between the second metal layers 124.

The first electrode 142 is disposed between the at least one first bump part 132 and the portion 152-1 of the first conductive semiconductor layer 152A, and is submounted through the first bump part 132. It is connected to the first metal layer 122 of 110. The second electrode 144 is disposed between the at least one second bump portion 134 and the second conductive semiconductor layer 156, and the second metal layer of the submount 110 is disposed through the second bump portion 134. 124 is connected.

Each of the first and second electrodes 142 and 144 in contact with the first and second conductivity-type semiconductor layers 152A and 156 may be formed of a metal, for example, Ag, Ni, Al, Rh, or Pd. , Ir, Ru, Mg, Zn, Pt, Au, Hf and optional combinations thereof.

Each of the first and second electrodes 142 and 144 may be a transparent conductive oxide (TCO). For example, each of the first and second electrodes 142 and 144 may be formed of the above-described metal material, indium tin oxide (ITO), indium zinc oxide (IZO), indium zinc tin oxide (IZTO), and indium aluminum zinc oxide (AZO). ), Indium gallium zinc oxide (IGZO), indium gallium tin oxide (IGTO), aluminum zinc oxide (AZO), antimony tin oxide (ATO), gallium zinc oxide (GZO), IrOx, RuOx, RuOx / ITO, Ni / IrOx / Au, and Ni / IrOx / Au / ITO, but are not limited to these materials. The first and second electrodes 142 and 144 may include a material in ohmic contact with the first and second conductivity-type semiconductor layers 152A and 156, respectively.

In addition, each of the first and second electrodes 142 and 144 may be formed in a single layer or multiple layers of a reflective electrode material having ohmic characteristics. If the first and second electrodes 142 and 144 play an ohmic role, a separate ohmic layer (not shown) may not be formed.

Meanwhile, the first reflective layer 170 is electrically opposed to the other portion 152-2 of the first conductive semiconductor layer 152A exposed by mesa etching, and is disposed on the submount 110. Here, the fact that the first reflective layer 170 is electrically separated from the other portion 152-2 of the first conductive semiconductor layer 152A is different from that of the other portion 152-2 of the first conductive semiconductor layer 152A. This means that no bumps are disposed between the first reflective layers 170. In contrast, a part 152-1 of the first conductivity type semiconductor layer 152A is electrically connected by the first metal layer 122 and the first bump part 132, and the second conductivity type semiconductor layer 156 is provided. ) Is electrically connected to the second metal layer 124 and the second bump part 134.

In addition, the second width W2 of the first reflective layer 170 may be larger than the first width W1 of the other portion 152-2 of the first conductive semiconductor layer 152A. If the second width W2 of the first reflective layer 170 is smaller than 10 μm, it may be difficult to perform the reflective function. If the second width W2 is larger than 1000 μm, the first reflective layer 170 may be considered in consideration of the entire upper width of the sub-mount 110. May not be possible. Accordingly, the second width W2 of the first reflective layer 170 may be 10 μm to 1000 μm, for example, at least 80 μm, but embodiments are not limited thereto.

In addition, the first reflective layer 170 may include first and second reflectors 170A and 170B. The first reflecting unit 170A is a portion facing the other portion 152-2 of the first conductivity type semiconductor layer 152A, and the second reflecting unit 170B is adjacent to the first reflecting unit 170A and is the first. The portion of the conductive semiconductor layer 152A that does not face the other portion 152-2.

The third width W3 of the first reflector 170A may be different from the fourth width W4 of the second reflector 170B. For example, the third width W3 of the first reflector 170A may be smaller than the fourth width W4 of the second reflector 170B.

In addition, the first reflecting unit 170A includes a first-first reflecting unit 170A-2 and a first-second reflecting unit 170A-1 and 170A-3. The first-first reflecting unit 170A-2 faces the first electrode 142 disposed under the other portion 152-2 of the first conductivity-type semiconductor layer 152A, and the first-second reflecting unit 170A -1 and 170A-3 face the other portion 152-2 of the first conductivity type semiconductor layer 152A.

In addition, the first length L1 of the first reflective layer 170 may be different from the second length L2 of the light emitting structure 150A. For example, as shown in FIG. 1, the first length L1 may be longer than the second length L2.

If the first reflective layer 170 is disposed, a third metal layer (not shown) is disposed instead of the first reflective layer 170, and the other portion 152-2 of the third metal layer and the first conductive semiconductor layer 152A is disposed. When the third bumps (not shown) electrically connecting them to each other are disposed, the reflected light 202 which does not escape the light emitting structures 150A and 150B is absorbed by the third bumps and converted into heat. Can be.

However, according to the embodiment, the light 200 emitted from the active layer 154A of the light emitting structure 150A may be reflected in the arrow direction 202 without escaping from the light emitting structure 150A. In this case, when the reflected light 202 escapes toward the sub-mount 110, the escaped light 202 is reflected by the first reflective layer 170 and exits 204 from the light emitting device 100A, thereby improving light extraction efficiency. Can be improved.

In addition, the surface of the other portion 152-2 of the first conductivity-type semiconductor layer 152A facing the first reflective layer 170 may have a roughness 152-3. In the case of FIG. 2, the roughness 152-3 is illustrated as not being disposed between the first electrode 142 and the first conductive semiconductor layer 152A, but embodiments are not limited thereto. That is, unlike illustrated in FIG. 2, the roughness 152-3 may be disposed between the first electrode 142 and the first conductivity type semiconductor layer 152A.

In addition, the exposed surface of the side portion 180 of the exposed light emitting structure 150A adjacent to the other portion 152-2 of the first conductive semiconductor layer 152A exposed by mesa etching may also have roughness. As such, since roughness is formed in each of the other portions 152-2 and the side portions 180 of the first conductive semiconductor layer 152A, the light 200 emitted from the active layer 154A emits light. If the reflected light does not escape, the reflected light 202 more easily escapes toward the sub-mount 110 and is reflected from the first reflective layer 170, and the reflected light 204 escapes the light emitting device 100A. The light extraction efficiency can be further improved.

3 shows a cross-sectional view of a light emitting element 100B of another embodiment.

The light emitting device 100B illustrated in FIG. 3 further includes a second reflective layer 172. Except for this, since the light emitting device 100B illustrated in FIG. 3 is the same as the light emitting device 100A illustrated in FIG. 2, the same reference numeral is used, and a description of overlapping portions will be omitted.

The second reflective layer 172 is disposed under the other portion 152-2 of the first conductive semiconductor layer 152A facing the first reflective layer 170. Here, as illustrated in FIG. 3, the second reflective layer 172 may be disposed in contact with the first electrode 142, but embodiments are not limited thereto. That is, unlike the example illustrated in FIG. 3, the second reflective layer 172 may be spaced apart from the first electrode 142.

If the light 210 emitted from the active layer 154A of the light emitting structure 150A does not escape the light emitting structure 150A, it may be reflected. In this case, the reflected light 212 may be reflected by the second reflective layer 172 and output 214, thereby improving light extraction efficiency.

4 is a sectional view of a light emitting device 100C according to still another embodiment.

In the light emitting device 100C illustrated in FIG. 4, the same reference numerals are used for the same parts as the light emitting device 100A illustrated in FIG. 2, and overlapping descriptions of the same parts will be omitted.

Referring to FIG. 4, the portion of the light emitting structure 150B that faces the first reflective layer 170 may be the active layer 154B instead of the other portion 152-2 of the first conductive semiconductor layer 152A. That is, a part 152-1 of the first conductivity type semiconductor layer 152A may be exposed by mesa etching, and the active layer 154B may be exposed by mesa etching. In this case, a portion of the light emitting structure 150B that is connected through the first bump part 132 and the first electrode 142 may be a mesa-etched first conductive semiconductor layer 152B, whereas the first reflective layer 170 may be Opposite portions correspond to mesa-etched active layer 154B.

In addition, a surface of the active layer 154B exposed by mesa etching facing the first reflective layer 170 may have roughness 152-4.

In addition, the first reflecting layer 170 may further include the third reflecting unit 170C as well as the first and second reflecting units 170A and 170B. The third reflector 170C faces at least one of the second electrode 144 and the second conductive semiconductor layer 156. For example, as illustrated in FIG. 4, the third reflector 170C may face the second conductivity type semiconductor layer 156.

In addition, the light emitting device 100C may further include a third reflective layer 174. The third reflective layer 174 may be disposed under a portion 152-1 of the mesa etched first conductive semiconductor layer 152B. The third reflective layer 174 may be disposed in contact with the first electrode 142 as illustrated in FIG. 4, but the embodiment is not limited thereto.

In addition, since the first reflective layer 170 is disposed, a separate metal deposition process for depositing the third reflective layer 174 may not be required.

Each of the first to third reflective layers 170, 172, and 174 described above may include silver (Ag), nickel (Ni), aluminum (Al), rhodium (Rh), palladium (Pd), iridium (Ir), and ruthenium (Ru). ), Magnesium (Mg), zinc (Zn), platinum (Pt), gold (Au), hafnium (Hf) and one or more of the materials consisting of two or more alloys thereof.

FIG. 5 is a graph illustrating brightness enhancement of light emitting devices 100A, 100B, and 100C according to an exemplary embodiment, and the horizontal axis is occupied (ie occupied by the first reflective layer 170 on the entire upper surface of the sub-mount 110). ) Area ratio, and the vertical axis represents the brightness enhancement rate.

Referring to FIG. 5, when the area ratio of the first reflective layer 170 of the entire upper surface of the submount 110 is 30% (190), the first reflective layer 170 of the entire upper surface of the submount 110 is greater. In the case where the area ratio is 70% (192), the brightness enhancement rate is further improved.

In order to maximize the brightness, the first reflective layer 170 is disposed on the submount 170 as wide as possible within the range that the first and second separation distances d1 and d2 are maintained at the minimum values allowed by the process error. can do. 1 and 2, the first separation distance d1 refers to a minimum distance from which the first reflective layer 170 and the second metal layer 124 are spaced apart from each other, and the second separation distance d2 is referred to. The minimum distance between the edge of the first reflective layer 170 and the edge of the sub-mount 110 is spaced apart from each other.

For example, when the area ratio of the first reflective layer 170 to the entire upper surface of the sub-mount 110 is 50% to 70% it can be seen that the brightness enhancement is further improved.

Hereinafter, a manufacturing method according to an embodiment of the light emitting device 100A illustrated in FIGS. 1 and 2 will be described as follows. However, other light emitting devices 100B and 100C may also be manufactured by the manufacturing method illustrated in FIGS. 6A to 6E. In addition, the light emitting device 100A illustrated in FIGS. 1 and 2 is not limited to the manufacturing method shown in FIGS. 6A to 6E and may be manufactured by various other manufacturing methods.

6A to 6E are cross-sectional views illustrating a method of manufacturing the light emitting device 100A according to the embodiment.

6A to 6C illustrate a manufacturing method of the upper structures 142, 144, 150A, and 160 of the light emitting device 100A illustrated in FIGS. 1 and 2, and shown in FIGS. 6D and 6E. The manufacturing method represents a method of manufacturing the lower structures 110, 122, 124, 132, 134 and 170 of the light emitting device 100A illustrated in FIGS. 1 and 2.

Referring to FIG. 6A, a substrate 160 is prepared. The substrate 160 may be formed of a light transmitting material, but is not limited thereto. For example, at least one of sapphire (Al ₂ O ₃ ), SiC, GaAs, GaN, ZnO, Si, GaP, InP, and Ge may be used. It may be formed as one, but is not limited thereto.

Subsequently, referring to FIG. 6A, the light emitting structure 150A is grown on the substrate 160. The light emitting structure 150A may be formed by sequentially growing the first conductivity type semiconductor layer 152A, the active layer 154A, and the second conductivity type semiconductor layer 156 on the substrate 160. The light emitting structure 150A may be formed of, for example, Metal Organic Chemical Vapor Deposition (MOCVD), Chemical Vapor Deposition (CVD), Plasma-Enhanced Chemical Vapor Deposition (PECVD), molecular beam growth. It may be formed using a method such as Molecular Beam Epitaxy (MBE), Hydride Vapor Phase Epitaxy (HVPE), but is not limited thereto.

6B, the first conductive semiconductor layer 152A, the active layer 154A, and the second conductive semiconductor layer 156 are mesa-etched to form a part 152 of the first conductive semiconductor layer 152A. -1) and the other part 152-2 are exposed.

6C, the first and second electrodes 142 and 144 may be disposed on a portion 152-1 of the exposed first conductive semiconductor layer 152A and on the second conductive semiconductor layer 156. Form each.

Referring to FIG. 6D, the sub-mount 110, the first and second metal layers 122 and 124, and the first reflective layer 170 are formed in separate processes while the processes illustrated in FIGS. 6A to 6C are performed. . If the first and second metal layers 122 and 124 and the first reflective layer 170 are made of the same material, they may be formed at the same time.

Subsequently, referring to FIG. 6E, first and second bump parts 132 and 134 are formed on the first and second metal layers 122 and 124, respectively.

Thereafter, the structure shown in FIG. 6C is rotated such that the substrate 160 is disposed on the top side, and then combined with the resultant shown in FIG. In this case, the first electrode 142 and the first metal layer 122 are coupled by the first bump part 132, and the second electrode 144 and the second metal layer 124 are connected by the second bump part 134. Is combined.

7 is a cross-sectional view of a light emitting device package 300 according to the embodiment.

The light emitting device package 300 according to the embodiment includes a light emitting device 100A, a substrate 310, first and second package bodies 320A and 320B, an insulator 330, and first and second wires 342 and 344. ) And the molding member 350. The light emitting device 100A is a light emitting device illustrated in FIGS. 1 and 2, and the detailed description thereof will be omitted using the same reference numerals. In addition to the light emitting device 100A illustrated in FIGS. 1 and 2, any one of the light emitting devices 100B and 100C illustrated in FIG. 3 or 4 may be implemented as the light emitting device package 300 as illustrated in FIG. 7. Of course.

The first and second package bodies 320A and 320B are disposed on the substrate 310. Here, the substrate 310 may be a printed circuit board (PCB), but is not limited thereto. In order to improve heat dissipation when the light emitting device 100A emits ultraviolet light, the first and second package bodies 320A and 320B may be made of aluminum, but are not limited thereto. Hereinafter, it is assumed that the first and second package bodies 320A and 320B are made of aluminum.

The sub mount 110 is disposed above the first package body 320A, but embodiments are not limited thereto. That is, the submount 110 may be disposed on the second package body 320B. The first and second metal layers 122 and 124 of the light emitting device 100A are connected to the first and second package bodies 320A and 320B by the first and second wires 342 and 344, respectively. When the first and second package bodies 320A and 320B are made of an aluminum material having electrical conductivity, the insulator 330 electrically separates the first package body 320A and the second package body 320B from each other. Play a role. Therefore, the first conductivity type semiconductor layer 152A is connected to the substrate 310 through the first electrode 142, the first bump part 132, the first wire 342, and the first package body 320A. . In addition, the second conductivity type semiconductor layer 154A is connected to the substrate 310 through the second electrode 144, the second bump part 134, the second wire 344, and the second package body 320B. .

The molding member 350 may be filled in the cavities formed by the first and second package bodies 320A and 320B to surround and protect the light emitting device 100A. In addition, the molding member 350 may include a phosphor to change the wavelength of light emitted from the light emitting device 100A.

A plurality of light emitting device packages according to another embodiment may be arranged on a substrate, and a light guide plate, a prism sheet, a diffusion sheet, a fluorescent sheet, or the like, which is an optical member, may be disposed on a path of light emitted from the light emitting device package. The light emitting device package, the substrate, and the optical member may function as a backlight unit or as a lighting unit. For example, the lighting system may include a backlight unit, a lighting unit, an indicator device, a lamp, and a street lamp.

8 illustrates a display device 800 including a light emitting device package according to an exemplary embodiment.

Referring to FIG. 8, the display device 800 includes a bottom cover 810, a reflector 820 disposed on the bottom cover 810, light emitting modules 830 and 835 that emit light, and a reflector 820. ) And a light guide plate 840 for guiding light emitted from the light emitting modules 830 and 835 to the front of the display device, and prism sheets 850 and 860 disposed in front of the light guide plate 840. An optical sheet, a display panel 870 disposed in front of the optical sheet, an image signal output circuit 872 connected to the display panel 870 and supplying an image signal to the display panel 870, and a display panel 870 It may include a color filter 880 disposed in front of the. Here, the bottom cover 810, the reflector 820, the light emitting modules 830 and 835, the light guide plate 840, and the optical sheet may form a backlight unit.

The light emitting module may include light emitting device packages 835 mounted on the substrate 830. Here, the substrate 830 may be a PCB or the like. The substrate 830 and the light emitting device package 835 may be the embodiments 310 and 300 illustrated in FIG. 7.

The bottom cover 810 may accommodate components in the display device 800. In addition, the reflective plate 820 may be provided as a separate component as shown in the drawing, or may be provided in the form of a high reflective material on the rear surface of the light guide plate 840 or the front surface of the bottom cover 810. .

Here, the reflective plate 820 may use a material having a high reflectance and being extremely thin, and may use polyethylene terephthalate (PET).

The light guide plate 840 may be formed of polymethyl methacrylate (PMMA), polycarbonate (PC), polyethylene (PE), or the like.

The first prism sheet 850 may be formed of a translucent 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 provided in the stripe type and the valley repeatedly as shown.

In addition, the direction of the floor and the valley of one surface of the support film in the second prism sheet 860 may be perpendicular to the direction of the floor and the valley of one surface of the support film in the first prism sheet 850. This is to evenly distribute the light transmitted from the light emitting module and the reflective sheet to the front surface of the display panel 1870.

Although not shown, a diffusion sheet may be disposed between the light guide plate 840 and the first prism sheet 850. The diffusion sheet may be made of a polyester and polycarbonate-based material, and may maximize the light projection angle through refraction and scattering of light incident from the backlight unit. The diffusion sheet is formed on a support layer including a light diffusing agent, a first layer and a second layer which are formed on the light exit surface (first prism sheet direction) and the light incident surface (reflective sheet direction) and do not include the light diffuser It may include.

In an embodiment, the diffusion sheet, the first prism sheet 850, and the second prism sheet 860 form an optical sheet, which optical sheet is made of another combination, for example, a micro lens array or a diffusion sheet and a micro lens array. Or a combination of one prism sheet and a micro lens array.

A liquid crystal display panel may be disposed on the display panel 870. In addition to the liquid crystal display panel, another type of display device that requires a light source may be provided.

9 illustrates a head lamp 900 including a light emitting device package according to an embodiment.

Referring to FIG. 9, the head lamp 900 includes a light emitting module 901, a reflector 902, a shade 903, and a lens 904.

The light emitting module 901 may include a plurality of light emitting device packages (not shown) disposed on a substrate (not shown). In this case, the light emitting device package may be the embodiment 300 illustrated in FIG. 7.

The reflector 902 reflects light 911 emitted from the light emitting module 901 in a predetermined direction, for example, the front 912.

The shade 903 is disposed between the reflector 902 and the lens 904, and a member that blocks or reflects a portion of the light reflected by the reflector 902 toward the lens 904 to achieve a light distribution pattern desired by the designer. As one side, the one side portion 903-1 and the other side portion 903-2 of the shade 903 may have different heights.

Light irradiated from the light emitting module 901 may be reflected by the reflector 902 and the shade 903 and then transmitted through the lens 904 toward the front of the vehicle body. The lens 904 may deflect forward light reflected by the reflector 902.

10 illustrates a lighting device 1000 including a light emitting device according to the embodiment.

Referring to FIG. 10, the lighting apparatus 1000 may include a cover 1100, a light source module 1200, a heat sink 1400, a power supply 1600, an inner case 1700, and a socket 1800. have. In addition, the lighting apparatus 1000 according to the embodiment may further include any one or more of the member 1300 and the holder 1500.

The light source module 1200 may include the light emitting devices 100A, 100B, and 100C illustrated in FIGS. 1 to 4, or the light emitting device package 300 illustrated in FIG. 7.

The cover 1100 may have a shape of a bulb or hemisphere, may be hollow, and may have a shape in which a portion thereof is opened. 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 combined with the heat sink 1400. The cover 1100 may have a coupling portion coupled to the heat sink 1400.

The inner surface of the cover 1100 may be coated with a milky paint. The milky 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 for the light from the light source module 1200 to be sufficiently scattered and diffused and emitted 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, but is not limited thereto and 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 heat sink 1400, and heat generated from the light source module 1200 may be conducted to the heat sink 1400. The light source module 1200 may include a light source 1210, a connection plate 1230, and a connector 1250.

The member 1300 may be disposed on an upper surface of the heat sink 1400, and has a plurality of light source units 1210 and a guide groove 1310 into which the connector 1250 is inserted. The guide groove 1310 may correspond to or be aligned with the substrate and the connector 1250 of the light source 1210.

The surface of the member 1300 may be coated or coated with a light reflecting material.

For example, the surface of the member 1300 may be coated or coated with a white paint. The member 1300 may reflect light reflected from the inner surface of the cover 1100 and returned toward the light source module 1200 in the direction of the cover 1100. Therefore, it is possible to improve the light efficiency of the lighting apparatus 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. Therefore, electrical contact may be made between the heat sink 1400 and the connection plate 1230. The member 1300 may be made of an insulating material to block an electrical short between the connection plate 1230 and the heat sink 1400. The radiator 1400 may receive heat from the light source module 1200 and heat from the power supply 1600 to radiate heat.

The holder 1500 blocks the accommodating groove 1719 of the insulating portion 1710 of the inner case 1700. Therefore, the power supply unit 1600 accommodated in the insulating unit 1710 of the inner case 1700 may be sealed. The holder 1500 may have a guide protrusion 1510, and the guide protrusion 1510 may have a hole through which the protrusion 1610 of the power supply 1600 passes.

The power supply unit 1600 processes or converts an electrical signal provided from the outside to provide the light source module 1200. The power supply 1600 may be accommodated in the accommodating groove 1725 of the inner case 1700, and may be sealed in the inner case 1700 by the holder 1500. The power supply 1600 may include a protrusion 1610, a guide 1630, a base 1650, and an extension 1670.

The guide part 1630 may have a shape protruding to the outside from one side of the base 1650. The guide part 1630 may be inserted into the holder 1500. A plurality of parts may be disposed on one surface of the base 1650. For example, a plurality of components may include, for example, a DC converter for converting an AC power provided from an external power source into a DC power source, a driving chip for controlling driving of the light source module 1200, and an ESD (ElectroStatic) to protect the light source module 1200. discharge) protection elements and the like, but is not limited thereto.

The extension 1670 may have a shape protruding to the outside from the other side of the base 1650. The extension 1670 may be inserted into the connection 1750 of the inner case 1700, and may receive an electrical signal from the outside. For example, the extension 1670 may have the same width or smaller than the connection portion 1750 of the inner case 1700. Each end of the "+ wire" and the "-wire" may be electrically connected to the extension 1670, and the other end of the "+ wire" and the "-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 where the molding liquid is hardened, so that the power supply 1600 can be fixed inside the inner case 1700.

Although described above with reference to the embodiments, which are merely examples and are not intended to limit the present invention. Those skilled in the art to which the present invention pertains should not be exemplified above without departing from the essential characteristics of the present embodiments. It will be appreciated that many variations and applications are possible. For example, each component specifically shown in the embodiment can be modified. And differences relating to these modifications and applications will have to be construed as being included in the scope of the invention defined in the appended claims.

100A, 100B, 100C: Light emitting element 110: Submount
122, 134: first and second metal layers 132, 134: first and second bump portions
142 and 144: first and second electrodes 142-1: part of the first electrode
142-2: other parts of the first electrode 150A and 150B: light emitting structure
152A and 152B: first conductive semiconductor layer 152-1: part of first conductive semiconductor layer
152-2: Other portion of the first conductivity type semiconductor layer 152-4: Roughness
154A and 154B: active layer 156: second conductive semiconductor layer
160: substrate 170A, 170B, 170C: reflector
170, 172, 174: reflective layer 300: light emitting device package
310: substrate 320A, 320B: package body
330: insulator 342, 344: wire
350: molding member 800: display device
810: bottom cover 820: reflector
830, 835, 901: Light emitting module 840: Light guide plate
850 and 860 prism sheet 870 display panel
872: image signal output circuit 880: color filter
900: head lamp 902: reflector
903: Shade 904: Lens
1000: lighting device 1100: cover
1200: light source module 1300: member
1400: radiator 1500: holder
1600: power supply unit 1700: inner case
1800: socket

Claims (14)

Submount;
A light emitting structure on the submount; The light emitting structure
Translucent substrate; And
A first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer under the light-transmissive substrate;
First and second metal layers disposed below the light emitting structure and spaced apart from each other on the sub-mount;
At least one first bump portion disposed between a portion of the first conductivity-type semiconductor layer exposed by mesa etching and the first metal layer;
At least one second bump part disposed between the second conductive semiconductor layer and the second metal layer; And
A first reflective layer electrically separated from and facing at least one of the other portion of the first conductivity-type semiconductor layer exposed by the mesa etching or the active layer exposed by the mesa etching, and disposed on the sub-mount,
The portion of the first conductive semiconductor layer and the other portion has a cross-sectional shape spaced apart from each other with the second conductive semiconductor layer therebetween,
The first reflective layer is disposed spaced apart from the first metal layer and the second metal layer,
The first reflective layer
A first reflector facing the other part of the first conductive semiconductor layer; And
A second reflector adjacent to the first reflector and not facing the other part of the first conductivity type semiconductor layer,
The light emitting device of claim 2, wherein the second reflector does not overlap the light emitting structure. The light emitting device of claim 1, wherein an area ratio of the first reflective layer in the entire upper surface of the submount is 50% to 70%. The light emitting device of claim 1, wherein a second width of the first reflective layer is greater than a first width of the other portion of the first conductive semiconductor layer. delete The light emitting device of claim 1, wherein a third width of the first reflecting portion is smaller than a fourth width of the second reflecting portion. According to claim 1,
A first electrode having a portion disposed between the at least one first bump portion and a portion of the first conductivity type semiconductor layer; And
A second electrode disposed between the at least one second bump part and the second conductive semiconductor layer;
The light emitting device of claim 1, wherein the portion and the other portion of the first electrode have a cross-sectional shape spaced apart from each other with the second conductive semiconductor layer interposed therebetween. The method of claim 6, wherein the first reflective layer
And a third reflector facing at least one of the second electrode and the second conductive semiconductor layer. The method of claim 6, wherein the first reflecting unit
A first-first reflecting portion facing the other portion of the first electrode disposed under the other portion of the first conductive semiconductor layer; And
A light emitting device comprising a 1-2 reflection portion facing the other portion of the first conductivity type semiconductor layer. The light emitting device of claim 1, wherein a surface of the other portion of the first conductive semiconductor layer facing the first reflective layer has roughness. The light emitting device of claim 1, wherein a first length of the first reflective layer is longer than a second length of the light emitting structure. 7. The light emitting device of claim 6, further comprising a second reflective layer disposed below the other portion of the first conductive semiconductor layer facing the first reflective layer. The light emitting device of claim 11, wherein the second reflective layer is disposed adjacent to the other portion of the first electrode. The light emitting device of claim 1, wherein a width of the first reflective layer is 10 μm to 1000 μm. The light emitting device of claim 1, wherein an exposed surface of a side of the exposed light emitting structure adjacent to the other portion of the first conductive semiconductor layer exposed by mesa etching has roughness.

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