KR102302856B1 - Light emitting device - Google Patents

Abstract

The light emitting device of the embodiment includes a substrate, a light emitting structure disposed under the substrate, a light emitting structure including a first conductivity type semiconductor layer, an active layer, and a second conductivity type semiconductor layer, an insulating layer disposed under the light emitting structure and having a light extraction pattern; , a reflective layer disposed between the light emitting structure and the insulating layer, the reflective layer, the second conductivity type semiconductor layer and the active layer are connected to the first conductivity type semiconductor layer, and are electrically connected to the second conductivity type semiconductor layer and the active layer by the insulating layer and a first electrode insulated from and a second electrode connected to the second conductivity-type semiconductor layer through the insulating layer.

Description

Light emitting device

The embodiment relates to a light emitting device.

A light emitting diode (LED: Light Emitting Diode) is a type of semiconductor device that converts electricity into light using characteristics of a compound semiconductor to send and receive signals or is used as a light source.

Group III-V nitride semiconductors are in the spotlight as a core material for light emitting devices such as light emitting diodes (LEDs) or laser diodes (LDs) due to their physical and chemical properties. have.

Since these light emitting diodes do not contain environmentally harmful substances such as mercury (Hg) used in conventional lighting fixtures such as incandescent and fluorescent lamps, they have excellent eco-friendliness, and have advantages such as long lifespan and low power consumption characteristics. are replacing them However, in the case of a conventional light emitting device, light emitted from the active layer is totally reflected due to a difference in refractive index around the active layer, is trapped inside, and cannot be emitted from the light emitting device, so there is a problem in that light extraction efficiency is deteriorated.

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

A light emitting device according to an embodiment includes a substrate; a light emitting structure disposed under the substrate and including a first conductivity type semiconductor layer, an active layer, and a second conductivity type semiconductor layer; an insulating layer disposed under the light emitting structure and having a light extraction pattern; a reflective layer disposed between the light emitting structure and the insulating layer; A first electrode that penetrates through the reflective layer, the second conductivity-type semiconductor layer, and the active layer, is connected to the first conductivity-type semiconductor layer, and is electrically insulated from the second conductivity-type semiconductor layer and the active layer by the insulating layer ; and a second electrode connected to the second conductivity-type semiconductor layer through the insulating layer.

For example, the light-emitting device may further include a conductive light-transmitting layer disposed between the light-emitting structure and the reflective layer. The light emitting device may further include a doping layer disposed between the conductive light-transmitting layer and the reflective layer. The doping layer may include ZnO and may be doped with a second conductivity type dopant. The reflective layer may have a pattern having the same shape as the light extraction pattern. The conductive light-transmitting layer is a light emitting device having the same shape as the light extraction pattern.

For example, the light extraction pattern may have a convex shape toward the active layer, and the convex shape may have at least one three-dimensional shape selected from a polyhedral shape, a conical shape, and a hemispherical shape. The height of the unit pattern in the hemispherical light extraction pattern may be 1.2 μm to 1.8 μm. In the light extraction pattern, an interval between unit patterns may be 0 to 1 μm. The conductive light-transmitting layer may have a thickness of 3 nm to 10 nm. A distance from the boundary between the active layer and the second conductivity-type semiconductor layer to the conductive light-transmitting layer and the light extraction pattern may be 203 nm to 210 nm. In addition, the doped layer may have a pattern of a broken shape without being connected in a direction perpendicular to the thickness direction of the light emitting structure.

A light emitting device package according to another embodiment includes a package body; the light emitting device disposed on the package body; a first pad electrically connected to the first electrode; a second pad electrically connected to the second electrode; and first and second lead frames electrically connected to the first and second pads, respectively, and spaced apart from each other.

The light emitting device according to the embodiment may have improved light extraction efficiency by scattering the light emitted from the active layer and totally reflected therein by the light extraction pattern of the insulating layer and outputting it to the outside.

1 is a cross-sectional view of a light emitting device according to an embodiment.
FIG. 2A is a cross-sectional view of a portion 'A' shown in FIG. 1 according to an embodiment, and FIG. 2B is a perspective view of a unit pattern in the light extraction pattern of the insulating layer shown in FIG. 2A.
3A is a cross-sectional view showing a portion 'A' shown in FIG. 1 according to another embodiment, and FIG. 3B is a perspective view of a unit pattern in the light extraction pattern of the insulating layer shown in FIG. 3A.
FIG. 4A is a cross-sectional view of a portion 'A' shown in FIG. 1 according to another embodiment, and FIG. 4B is a perspective view of a unit pattern in the light extraction pattern of the insulating layer shown in FIG. 4A.
5A to 5C are perspective views and cross-sectional views of an insulating layer according to an embodiment, respectively.
6 is a cross-sectional view of a light emitting device according to another embodiment.
7 is a cross-sectional view of a light emitting device according to another embodiment.
8A to 8E are cross-sectional views illustrating a method of manufacturing the light emitting device illustrated in FIG. 7 .
9 is a graph showing light extraction efficiency according to the height of the light extraction pattern of the insulating layer shown in FIGS. 1 to 4B and FIGS. 6 and 7 .
10 is a graph showing the light extraction efficiency for each separation distance of the unit pattern in the light extraction pattern of the insulating layer.
11 is a graph showing light extraction efficiency and light transmittance according to the thickness of the conductive light transmitting layer.
12 is a graph showing transmittance according to thickness of the conductive light-transmitting layer according to the wavelength of light emitted from the active layer.
13 is a cross-sectional view of a light emitting device according to a comparative example.
14 is a cross-sectional view of a light emitting device package according to an embodiment.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings to help the understanding of the present invention by giving examples, and to explain the present invention in detail. However, the embodiments according to the present invention may be modified in various other forms, and the scope of the present invention should not be construed as being limited to the embodiments described in detail below. The embodiments of the present invention are provided to more completely explain the present invention to those of ordinary skill in the art.

In the description of this embodiment, in the case where it is described as being formed on "on or under" of each element, above (above) or below (below) ( on or under includes both elements in which two elements are in direct contact with each other or in which one or more other elements are disposed between the two elements indirectly.

In addition, when expressed as "up (up)" or "down (on or under)", a meaning of not only an upward direction but also a downward direction may be included based on one element.

Also, as used hereinafter, relational terms such as "first" and "second," "upper/upper/above" and "lower/lower/below" refer to any physical or logical relationship or It may be used only to distinguish one entity or element from another, without requiring or implying an order.

1 is a cross-sectional view of a light emitting device 100A according to an embodiment.

The light emitting device 100A illustrated in FIG. 1 includes a substrate 110 , a light emitting structure 120 , an insulating layer (or a passivation layer) 130 , a reflective layer 140 , first and second electrodes (or , contact layers) 152 and 154 and a conductive light-transmitting layer 160 .

The substrate 110 may include a conductive material or a non-conductive material. For example, the substrate 110 may _{include at least one of sapphire (Al 2} 0 ₃ ), GaN, SiC, ZnO, GaP, InP, Ga ₂ 0 ₃ , GaAs, and Si. ) is not limited to the material of

In order to improve a difference in coefficient of thermal expansion (CTE) and a lattice mismatch between the substrate 110 and the light emitting structure 120 , a buffer layer (or a transition layer) (not shown) between the substrate 110 and the light emitting structure 120 . ) may be further arranged. The buffer layer may include, for example, at least one material selected from the group consisting of Al, In, N, and Ga, but is not limited thereto. In addition, the buffer layer may have a single-layer or multi-layer structure.

At the boundary between the substrate 110 and the light emitting structure 120 , the substrate 110 may have a pattern 112 . The pattern 112 may have various cross-sectional shapes to help light emitted from the active layer 124 escape from the light emitting device 100A. For example, the substrate 110 may be a patterned sapphire substrate (PSS).

The light emitting structure 120 is disposed under the substrate 110 , and may include a first conductivity type semiconductor layer 122 , an active layer 124 , and a second conductivity type semiconductor layer 126 .

The first conductivity type semiconductor layer 122 is disposed under the substrate 110 , and may be implemented as a compound semiconductor of group III-V or group II-VI doped with a first conductivity type dopant. When the first conductivity-type semiconductor layer 122 is an n-type semiconductor layer, the first conductivity-type dopant is an n-type dopant and may include Si, Ge, Sn, Se, and Te, but is not limited thereto.

For example, the first conductivity type semiconductor layer 122 has _{a composition formula of Al x} In _y Ga _(1-xy) N (0≤x≤1, 0≤y≤1, 0≤x+y≤1) It may include a semiconductor material. The first conductivity type semiconductor layer 122 may include any one or more of GaN, InN, AlN, InGaN, AlGaN, InAlGaN, AlInN, AlGaAs, InGaAs, AlInGaAs, GaP, AlGaP, InGaP, AlInGaP, and InP.

The active layer 124 is disposed between the first conductivity type semiconductor layer 122 and the second conductivity type semiconductor layer 126 , and includes electrons (or holes) injected through the first conductivity type semiconductor layer 122 and the second conductivity type semiconductor layer 122 . This is a layer in which holes (or electrons) injected through the two-conductivity semiconductor layer 126 meet each other and emit light having an energy determined by an energy band intrinsic to the material constituting the active layer 124 . The active layer 124 may include at least one of a single well structure, a multi-well structure, a single quantum well structure, a multi-quantum well (MQW) structure, a quantum-wire structure, or a quantum dot structure. can be formed into one.

The well layer/barrier layer of the active layer 124 may be formed of any one or more pair structure of InGaN/GaN, InGaN/InGaN, GaN/AlGaN, InAlGaN/GaN, GaAs (InGaAs)/AlGaAs, GaP (InGaP)/AlGaP. However, the present invention is not limited thereto. The well layer may be formed of a material having a bandgap energy lower than the bandgap energy of the barrier layer.

A conductive cladding layer (not shown) may be formed on and/or below the active layer 124 . The conductive clad layer may be formed of a semiconductor having a higher bandgap energy than that of the barrier layer of the active layer 124 . For example, the conductive clad layer may include GaN, AlGaN, InAlGaN, or a superlattice structure. In addition, the conductivity-type cladding layer may be doped with n-type or p-type.

The second conductivity type semiconductor layer 126 is disposed under the active layer 124 and may be formed of a semiconductor compound. The second conductivity type semiconductor layer 126 may be implemented with a compound semiconductor such as group III-V or group II-VI. For example, the second conductivity type semiconductor layer 126 _{includes 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). can do. The second conductivity type semiconductor layer 126 may be doped with a second conductivity type dopant. When the second conductivity-type semiconductor layer 126 is a p-type semiconductor layer, the second conductivity-type dopant is a p-type dopant and may include Mg, Zn, Ca, Sr, Ba, or the like.

The first conductivity-type semiconductor layer 122 may be implemented as an n-type semiconductor layer, and the second conductivity-type semiconductor layer 126 may be implemented as a p-type semiconductor layer. Alternatively, the first conductivity-type semiconductor layer 122 may be implemented as a p-type semiconductor layer, and the second conductivity-type semiconductor layer 126 may be implemented as an n-type semiconductor layer.

The light emitting structure 120 may be implemented as any one of an n-p junction structure, a p-n junction structure, an n-p-n junction structure, and a p-n-p junction structure.

When the light emitting device 100A illustrated in FIG. 1 is implemented in a flip chip bonding structure, the light emitted from the active layer 124 passes through the first conductive semiconductor layer 122 and the substrate 110 . can be ejected. To this end, the first conductivity-type semiconductor layer 122 and the substrate 110 may be made of a material having light transmittance. In this case, the second conductivity-type semiconductor layer 126 may be made of a material having light transmission or non-transmission properties or a material having reflection, but the embodiment may not be limited to a specific material.

Meanwhile, the insulating layer 130 is disposed under the light emitting structure 120 , between the first electrode 152 and the second conductivity-type semiconductor layer 126 , between the first electrode 152 and the active layer 124 , and It may be disposed between the first electrode 152 and the reflective layer 140 . Accordingly, each of the second conductivity-type semiconductor layer 126 , the active layer 124 , and the reflective layer 140 may be electrically insulated from the first electrode 152 by the insulating layer 130 .

In addition, when the light-emitting device 100A includes the conductive light-transmitting layer 160 as shown in FIG. 1 , the insulating layer 130 is disposed between the conductive light-transmitting layer 160 and the first electrode 152 , These 152 and 160 may be electrically isolated from each other.

Also, according to an embodiment, the insulating layer 130 may have a light extraction pattern. At this time, when having the light extraction pattern as shown in FIG. 1 , the insulating layer 130A includes the conductive light-transmitting layer 160 and the reflective layer 140 in the thickness direction (eg, the z-axis direction) of the light emitting structure 120 . ) can also be placed between

According to an embodiment, the light extraction pattern of the insulating layer 130 may have various shapes. Hereinafter, the light extraction pattern of the insulating layer 130 will be looked at with reference to the accompanying FIGS. 2A to 4B as follows.

2A, 3A, and 4A are cross-sectional views according to the embodiments (A1, A2, A3) of part 'A' shown in FIG. 1, and FIGS. 2B, 3B and 4B are FIGS. 2A, 3A, and 4B A perspective view of a unit pattern in the light extraction pattern of the insulating layer 130 shown in 4a is respectively shown.

According to an embodiment, the light extraction pattern of the insulating layer 130 may have various polyhedral shapes such as a tetrahedron or a pentahedron convex toward the active layer 124 . For example, the light extraction pattern of the insulating layer 130 may have a rectangular cross-sectional shape as shown in FIG. 2A . In this case, the unit pattern of the light extraction pattern of the insulating layer 130 may have a cylindrical three-dimensional shape as shown in FIG. 2B .

According to another embodiment, the light extraction pattern of the insulating layer 130 may have a convex semicircular cross-sectional shape toward the active layer 124 as shown in FIG. 3A . In this case, the unit pattern of the light extraction pattern of the insulating layer 130 may have a hemispherical three-dimensional shape as shown in FIG. 3B .

According to another embodiment, the light extraction pattern of the insulating layer 130 may have a convex triangular cross-sectional shape toward the active layer 124 as shown in FIG. 4A . In this case, the unit pattern of the light extraction pattern of the insulating layer 130 may have a conical three-dimensional shape as shown in FIG. 4B .

In the light extraction pattern of the insulating layer 130 shown in FIGS. 2A, 3A and 4A , the unit patterns are spaced apart by a predetermined distance d. In addition, each unit pattern illustrated in FIGS. 2A, 2B, 3A, 3B, 4A, and 4B may have a predetermined height h.

5A to 5C are perspective views and cross-sectional views of the insulating layer 130 according to an embodiment, respectively. In particular, FIG. 5B is a perspective view of part 'B' shown in FIG. 5A , and FIG. 5C is a cross-sectional view taken along line II' shown in FIG. 5B .

If the insulating layer 130 has a light extraction pattern in which a unit pattern of a hemispherical three-dimensional shape is repeated, and the separation distance d between each unit pattern is '0', the light extraction pattern of the insulating layer 130 is shown in FIG. It may be as shown in 5a to 5c.

The insulating layer 130 may be formed in a multi-layered or at least two multi-layered structure, and may include at least one of _{SiO 2} , TiO ₂ , ZrO ₂ , Si ₃ N ₄ , Al ₂ O ₃ , or MgF _{2 .} In addition, the insulating layer 130 may include a distributed Bragg reflector (DBR) or an omni-directional reflector (ODR). If the insulating layer 130 includes DBR and ODR, the insulating layer 130 may perform both an insulating function and a reflective function of the reflective layer 140 . In this case, the reflective layer 140 may be omitted.

The DBR may have a structure in which a first layer (not shown) and a second layer (not shown) having different refractive indices are alternately stacked at least once or more. DBR may be an electrically insulating material. For example, the first layer may be a first dielectric layer such as _{TiO 2 ,} and the second layer may include a second dielectric layer such as _{SiO 2 .} For example, the DBR _{may have a structure in which TiO 2} /SiO ₂ layers are stacked at least once. A thickness of each of the first layer and the second layer may be λ/4, and λ may be a wavelength of light generated in the light emitting cell.

The ODR may have a structure in which a metal reflective layer (not shown) and a low refractive index layer are formed on the metal reflective layer. The metal reflective layer may be Ag or Al, and the low refractive index layer may be a transparent material such as _{SiO 2} , Si ₃ N _{4 , or MgO.} Alternatively, the ODR structure may be a structure in which a SiO ₂ layer and a TiO ₂ layer are repeatedly stacked as a pair, but the embodiment is not limited thereto.

Meanwhile, referring back to FIG. 1 , the reflective layer 140 may be disposed between the light emitting structure 120 and the insulating layer 130 . The reflective layer 140 serves to reflect light emitted from the active layer 124 and traveling in the -z-axis direction, which is the thickness direction of the light emitting structure 120 . To this end, the reflective layer 140 may be made of a reflective material capable of reflecting light, for example, a metallic material such as silver (Ag), but the embodiment is not limited to the material of the reflective layer 140 .

1, 2A, 3A, and 4A , the reflective layer 140 may have a pattern having the same shape as the light extraction pattern of the insulating layer 130 . For example, as illustrated in FIGS. 1 and 2A , when the light extraction pattern of the insulating layer 130 has a rectangular cross-sectional shape, the reflective layer 140 may also have a rectangular cross-sectional shape. Alternatively, as illustrated in FIG. 3A , when the insulating layer 130 has a semi-circular cross-sectional shape, the reflective layer 140 may also have a semi-circular cross-sectional shape. Alternatively, as illustrated in FIG. 4A , when the insulating layer 130 has a triangular cross-sectional shape, the reflective layer 140 may also have a triangular cross-sectional shape.

Alternatively, unlike shown in FIGS. 1, 2A, 3A, and 4A , the reflective layer 140 may have a pattern having a shape different from that of the light extraction pattern of the insulating layer 130 . For example, when the light extraction pattern of the insulating layer 130 has a rectangular cross-sectional shape as illustrated in FIGS. 1 and 2A , the reflective layer 140 may have a truncated rectangular cross-sectional shape. Alternatively, when the insulating layer 130 has a semicircular cross-sectional shape as illustrated in FIG. 3A , the reflective layer 140 may have a truncated semicircular cross-sectional shape. Alternatively, when the insulating layer 130 has a triangular cross-sectional shape as illustrated in FIG. 4A , the reflective layer 140 may have a truncated triangular cross-sectional shape.

Meanwhile, the first electrode 152 penetrates the insulating layer 130 , the reflective layer 140 , the second conductivity type semiconductor layer 126 , and the active layer 124 to be electrically connected to the first conductivity type semiconductor layer 122 . can That is, the first electrode 152 may be implemented in the form of a through electrode, but the embodiment is not limited thereto. That is, according to another embodiment, although not shown, the first electrode 152 bypasses the reflective layer 140 , the second conductivity type semiconductor layer 126 , and the active layer 124 to form the first conductivity type semiconductor layer ( 122) and may be electrically connected.

If the light emitting device 100A includes the conductive light-transmitting layer 160 , the first electrode 152 includes the insulating layer 130 , the reflective layer 140 , the conductive light-transmitting layer 160 , and the second conductive semiconductor layer. It may be electrically connected to the first conductivity-type semiconductor layer 122 through the 126 and the active layer 124 .

If the light emitting device 100A does not include the conductive light-transmitting layer 160 as illustrated in FIG. 1 , the second electrode 154 penetrates the insulating layer 130 and passes through the reflective layer 140 . It may be electrically connected to the conductive semiconductor layer 126 . Alternatively, unlike illustrated in FIG. 1 , the second electrode 154 may be directly connected to the second conductivity-type semiconductor layer 126 through the insulating layer 130 and the reflective layer 140 .

Alternatively, when the light emitting device 100A includes the conductive light-transmitting layer 160 as illustrated in FIG. 1 , the second electrode 154 penetrates the insulating layer 130 to the reflective layer 140 and the conductive light-transmitting layer ( It may be electrically connected to the second conductivity type semiconductor layer 126 via 160 . Alternatively, unlike shown in FIG. 1 , the second electrode 154 may be directly connected to the second conductivity-type semiconductor layer 126 through the insulating layer 130 , the reflective layer 140 , and the conductive light-transmitting layer 160 . have.

Each of the first and second electrodes 152 and 154 may include a material in ohmic contact to perform an ohmic role, so that a separate ohmic layer (not shown) may not need to be disposed, and a separate ohmic layer may include the first and second ohmic layers. It may be disposed above or below each of the second electrodes 152 and 154 .

Each of the first and second electrodes 152 and 154 is formed of any material that can reflect or transmit light emitted from the active layer 124 without absorbing it and can be grown on the insulating layer 130 with good quality. can be For example, each of the first and second electrodes 152 and 154 may be formed of a metal, Ag, Ni, Al, Rh, Pd, Ir, Ru, Mg, Zn, Pt, Au, Hf, and their It can be made in optional combinations.

Meanwhile, the conductive light-transmitting layer 160 may be disposed between the light-emitting structure 120 and the reflective layer 140 and between the light-emitting structure 120 and the insulating layer 130 . Just as the reflective layer 140 has a light extraction pattern of the same shape or a different shape as that of the insulating layer 130 , the conductive light-transmitting layer 160 is an insulating layer as illustrated in FIGS. 1 , 2A , 3A and 4A . Unlike 130, it may not have a light extraction pattern.

The conductive light-transmitting layer 160 may be TCO (Transparent Transparent Conductive Oxide). For example, the conductive light-transmitting layer 160 may include indium tin oxide (ITO), indium zinc oxide (IZO), indium zinc tin oxide (IZTO), indium aluminum zinc oxide (IAZO), indium gallium zinc oxide (IGZO), or IGTO. (indium gallium tin oxide), aluminum zinc oxide (AZO), antimony tin oxide (ATO), gallium zinc oxide (GZO), IrOx, RuOx, RuOx/ITO, Ni/IrOx/Au, and Ni/IrOx/Au/ITO It may include at least one of, but is not limited to these materials.

The conductive light-transmitting layer 160 may serve to assist the function of the second electrode 154 together with the reflective layer 140 . That is, the second conductivity-type carrier introduced through the second electrode 154 may be supplied to the second conductivity-type semiconductor layer 126 through the reflective layer 140 and the conductive light-transmitting layer 160 . In some cases, the conductive light-transmitting layer 160 may be omitted.

6 is a cross-sectional view of a light emitting device 100B according to another embodiment.

The light emitting device 100B illustrated in FIG. 6 includes a substrate 110 , a light emitting structure 120 , an insulating layer 130 , a reflective layer 140 , first and second electrodes 152 and 154 , and a conductive light-transmitting layer 160 . ) may be included.

The conductive light-transmitting layer 160 shown in FIG. 1 does not have a light extraction pattern, whereas the conductive light-transmitting layer 160 shown in FIG. 6 has a light extraction pattern. Except for this, the light emitting device 100B shown in FIG. 6 is the same as the light emitting device 100A shown in FIG. 1 , and thus overlapping descriptions will be omitted. That is, the substrate 110 shown in FIG. 6 , the light emitting structure 120 , the insulating layer 130 , the reflective layer 140 , and the first and second electrodes 152 and 154 are the substrate 110 shown in FIG. 1 . , corresponding to the light emitting structure 120 , the insulating layer 130 , the reflective layer 140 , and the first and second electrodes 152 and 154 , respectively.

The conductive light-transmitting layer 160 illustrated in FIG. 6 may have a pattern having the same shape as the light extraction pattern of the insulating layer 130 . For example, as shown in FIG. 6 , when the light extraction pattern of the insulating layer 130 has a rectangular cross-sectional shape, the conductive light-transmitting layer 160 may also have a rectangular cross-sectional shape.

Alternatively, although not shown, when the insulating layer 130 has a semi-circular cross-sectional shape as illustrated in FIG. 3A , the conductive light-transmitting layer 160 may also have a semi-circular cross-sectional shape. Alternatively, when the insulating layer 130 has a triangular cross-sectional shape as illustrated in FIG. 4A , the conductive light-transmitting layer 160 may also have a triangular cross-sectional shape.

Alternatively, although not shown, the conductive light-transmitting layer 160 may have a pattern having a shape different from that of the light extraction pattern of the insulating layer 130 . While the light extraction pattern of the insulating layer 130 has a rectangular cross-sectional shape as shown in FIGS. 1, 2A, and 6 , the conductive light-transmitting layer 160 may have a light extraction pattern of a truncated square cross-sectional shape. . Alternatively, although not shown, the insulating layer 130 may have a semicircular cross-sectional shape as illustrated in FIG. 3A , while the conductive light-transmitting layer 160 may have a pattern of a truncated semicircular cross-sectional shape. Alternatively, the insulating layer 130 may have a triangular cross-sectional shape as illustrated in FIG. 4A , while the conductive light-transmitting layer 160 may have a truncated triangular cross-sectional shape.

7 is a cross-sectional view of a light emitting device 100C according to another embodiment.

The light emitting device 100C illustrated in FIG. 7 includes a substrate 110 , a light emitting structure 120 , an insulating layer 130 , a reflective layer 140 , first and second electrodes 152 and 154 , and a conductive light-transmitting layer 160 . ) and a doped layer 170 .

While the light emitting device 100A shown in FIG. 1 does not include the doped layer 170 , the light emitting device 100A shown in FIG. 7 may include the doped layer 170 . That is, as shown in FIG. 7 instead of the insulating layer 130 at the position of the insulating layer 130 surrounded by the reflective layer 140 and the conductive light-transmitting layer 160 in the light emitting device 100A shown in FIG. 1 . A doped layer 170 may be positioned. Except for this, the light emitting device 100C shown in FIG. 7 is the same as the light emitting device 100A shown in FIG. 1 , and thus overlapping descriptions will be omitted. That is, the substrate 110 , the light emitting structure 120 , the insulating layer 130 , the reflective layer 140 , the first and second electrodes 152 and 154 , and the conductive light-transmitting layer 160 shown in FIG. 7 are shown in FIG. 1 . Each corresponds to the substrate 110 , the light emitting structure 120 , the insulating layer 130 , the reflective layer 140 , the first and second electrodes 152 and 154 , and the conductive light-transmitting layer 160 shown in FIG.

The doped layer 170 may be disposed between the conductive light-transmitting layer 160 and the reflective layer 140 . That is, the doped layer 170 may be disposed surrounded by the bottom surface 160A of the conductive light-transmitting layer 160 and the reflective layer 140 . For example, the doped layer 170 may include ZnO and may be doped with a second conductivity type dopant. When the doped layer 170 includes ZnO, the second conductivity type dopant may be aluminum (Al), but the embodiment is not limited to the material of the doped layer 170 and the type of the second conductivity type dopant.

The doped layer 170 may have a pattern of a broken shape without being connected in a direction (eg, a y-axis direction) perpendicular to a thickness direction (eg, a z-axis direction) of the light emitting structure 120 .

In the light emitting devices 100A, 100B, and 100C according to the embodiment, as long as the insulating layer 130 can have a light extraction pattern, the embodiment is the presence or absence of each light extraction pattern of the reflective layer 140 and the conductive light-transmitting layer 160 or It is not limited to the shape of the light extraction pattern.

Hereinafter, a method of manufacturing the light emitting device 100C shown in FIG. 7 will be described with reference to FIGS. 8A to 8E . It goes without saying that the light emitting devices 100A and 100B shown in FIG. 1 or 6 may be manufactured through the manufacturing method described below.

8A to 8E are cross-sectional views illustrating a method of manufacturing the light emitting device 100C illustrated in FIG. 7 .

Referring to FIG. 8A , a substrate 110 is prepared. The substrate 110 may be prepared of a conductive material or a non-conductive material. For example, the substrate 110 may _{include at least one of sapphire (Al 2} 0 ₃ ), GaN, SiC, ZnO, GaP, InP, Ga ₂ 0 ₃ , GaAs, and Si. ) is not limited to the material of

In this case, illustration of the pattern 112 formed on the substrate 110 is omitted for convenience of description.

Thereafter, a first conductivity type semiconductor layer 122 , an active layer 124 , and a second conductivity type semiconductor layer 126 are sequentially formed on the substrate 110 as the light emitting structure 120 . Specifically, it is as follows.

A first conductivity type semiconductor layer 122 is formed on the substrate 110 . The first conductivity type semiconductor layer 122 may be formed of a compound semiconductor of group III-V or group II-VI doped with a first conductivity type dopant. When the first conductivity-type semiconductor layer 122 is an n-type semiconductor layer, the first conductivity-type dopant is an n-type dopant and may include Si, Ge, Sn, Se, and Te, but is not limited thereto.

For example, the first conductivity type semiconductor layer 122 has _{a composition formula of Al x} In _y Ga _(1-xy) N (0≤x≤1, 0≤y≤1, 0≤x+y≤1) It may be formed by a semiconductor material. The first conductivity type semiconductor layer 122 may include any one or more of GaN, InN, AlN, InGaN, AlGaN, InAlGaN, AlInN, AlGaAs, InGaAs, AlInGaAs, GaP, AlGaP, InGaP, AlInGaP, and InP.

Thereafter, an active layer 124 is formed on the first conductivity-type semiconductor layer 122 . The active layer 124 may include at least one of a single well structure, a multi-well structure, a single quantum well structure, a multi-quantum well (MQW) structure, a quantum-wire structure, or a quantum dot structure. can be formed into one.

The well layer/barrier layer of the active layer 124 may be formed of any one or more pair structure of InGaN/GaN, InGaN/InGaN, GaN/AlGaN, InAlGaN/GaN, GaAs (InGaAs)/AlGaAs, GaP (InGaP)/AlGaP. However, the present invention is not limited thereto. The well layer may be formed of a material having a bandgap energy lower than the bandgap energy of the barrier layer.

A conductive cladding layer (not shown) may be formed on and/or below the active layer 124 . The conductive clad layer may be formed of a semiconductor having a higher bandgap energy than that of the barrier layer of the active layer 124 . For example, the conductive clad layer may include GaN, AlGaN, InAlGaN, or a superlattice structure. In addition, the conductivity-type cladding layer may be doped with n-type or p-type.

Thereafter, a second conductivity type semiconductor layer 126 is formed on the active layer 124 . The second conductivity type semiconductor layer 126 may be formed of a semiconductor compound. The second conductivity type semiconductor layer 126 may be formed of a compound semiconductor such as group III-V or group II-VI. For example, the second conductivity type semiconductor layer 126 is made _{of 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). can be formed. The second conductivity type semiconductor layer 126 may be doped with a second conductivity type dopant. When the second conductivity-type semiconductor layer 126 is a p-type semiconductor layer, the second conductivity-type dopant is a p-type dopant and may include Mg, Zn, Ca, Sr, Ba, or the like.

The light emitting structure 120 may be formed by, for example, metal organic chemical vapor deposition (MOCVD), chemical vapor deposition (CVD), plasma-enhanced chemical vapor deposition (PECVD), or molecular beam growth. It may be formed using a method such as Molecular Beam Epitaxy (MBE) or Hydride Vapor Phase Epitaxy (HVPE), but is not limited thereto.

Thereafter, the conductive light-transmitting layer 160 is formed on the light-emitting structure 120 . The light-transmitting conductive layer 160 may be formed of TCO (Transparent Transparent Conductive Oxide). For example, the conductive light-transmitting layer 160 may include indium tin oxide (ITO), indium zinc oxide (IZO), indium zinc tin oxide (IZTO), indium aluminum zinc oxide (IAZO), indium gallium zinc oxide (IGZO), or IGTO. (indium gallium tin oxide), aluminum zinc oxide (AZO), antimony tin oxide (ATO), gallium zinc oxide (GZO), IrOx, RuOx, RuOx/ITO, Ni/IrOx/Au, and Ni/IrOx/Au/ITO It may be formed by at least one of, but is not limited to these materials.

Thereafter, referring to FIG. 8B , the conductive light-transmitting layer 160 , the second conductivity-type semiconductor layer 126 , and the active layer 124 are sequentially mesa-etched, passing through them 160 , 126 , and 124 . A first through hole H1 exposing the first conductivity type semiconductor layer 122 is formed.

Thereafter, referring to FIG. 8C , a doping layer 170 is formed on the conductive light-transmitting layer 160 around the first through hole H1 . The doped layer 170 may be formed by various methods. As an example, after a ZnO layer made of ZnO is formed on the conductive light-transmitting layer 160 , the doped layer 170 may be formed by doping the ZnO layer with aluminum as a second conductivity-type dopant.

Thereafter, referring to FIG. 8D , the reflective layer 140 is formed on the doped layer 170 . In this case, the reflective layer 140 is not formed in the first through hole H1. The reflective layer 140 may be formed of a reflective material capable of reflecting light, for example, a metal material such as silver (Ag), but the embodiment is not limited to the material of the reflective layer 140 .

Thereafter, referring to FIG. 8E , the insulating material 130 is deposited on the reflective layer 140 while filling the first through hole H1 . Thereafter, the insulating material 130 is etched to form a second through hole H2 exposing the first conductivity type semiconductor layer 122 and a third through hole H3 exposing the reflective layer 140 . As a result, the insulating layer 130 may be formed.

The insulating layer 130 may be formed of a multilayer or at least two multilayer structures, and may be formed of at least one of _{SiO 2} , TiO ₂ , ZrO ₂ , Si ₃ N ₄ , Al ₂ O ₃ , or MgF _{2 .} . In addition, the insulating layer 130 may be formed in the form of a diffuse Bragg reflective layer (DBR) or an omnidirectional reflective layer (ODR).

Thereafter, as shown in FIG. 7 , a metal material for forming the first and second electrodes 152 and 154 is buried in the second and third through holes H2 and H3 to form the first and second electrodes ( 152, 154). By forming each of the first and second electrodes 152 and 154 with a material in ohmic contact, the ohmic role is performed, thereby eliminating the need to form a separate ohmic layer (not shown). Alternatively, a separate ohmic layer may be formed above or below each of the first and second electrodes 152 and 154 .

Each of the first and second electrodes 152 and 154 is formed of any material that can reflect or transmit light emitted from the active layer 124 without absorbing it and can be grown on the insulating layer 130 with good quality. can be For example, each of the first and second electrodes 152 and 154 may be formed of a metal, Ag, Ni, Al, Rh, Pd, Ir, Ru, Mg, Zn, Pt, Au, Hf, and their It can be formed in optional combinations.

Hereinafter, the characteristics of the light emitting devices 100A to 100C according to the embodiment having the above-described configuration will be described with reference to the accompanying drawings.

9 is a graph showing the light extraction efficiency according to the height (h) of the light extraction pattern of the insulating layer 130 shown in FIGS. 1 to 4B and FIGS. 6 and 7 , wherein the horizontal axis indicates the height (h) and the vertical axis represents the light extraction efficiency.

When the length L of the bottom surface of the unit pattern in the light extraction pattern of the insulating layer 130 is 4.5 μm, the height h is changed from 0 to 1.8 μm while the cylindrical shape shown in FIGS. 2A and 2B, FIGS. 3A and 3A and The light extraction efficiencies obtained for each of the hemispherical shape shown in FIG. 3B and the cone shape shown in FIGS. 4A and 4B are shown in Table 1 below.

division cylindrical hemispherical conical Height (h) (μm) Light extraction efficiency (%) Light extraction efficiency (%) Light extraction efficiency (%) 0 26 26 26 0.6 50 53 48 1.2 48 61 57 1.5 49 63 58 1.8 48 61 59

Referring to Table 1 and FIG. 9 , when the height h is '0', it means that when there is no light extraction pattern, that is, the insulating layer 130 is flat. Therefore, it can be seen that the light extraction efficiency is 26% when there is no light extraction pattern, whereas when the height h is not '0', that is, when the light extraction pattern is present, the light extraction pattern is higher than 26%. In addition, the shape of the unit pattern in the light extraction pattern of the insulating layer 130 is the hemispherical 200 shown in FIG. 3b rather than the cylindrical 204 shown in FIG. 2b or the conical 202 shown in FIG. 4b. It can be seen that the light extraction efficiency is higher. For example, when the unit pattern has a hemispherical shape, when the height h of the unit pattern is 1.2 μm to 1.8 μm, it can be seen that the light extraction efficiency is 60% or more. In particular, it can be seen that the light extraction efficiency is improved by 63% when the unit pattern is hemispherical and the height h of the unit pattern is 1.5 μm.

10 shows when the light extraction pattern of the insulating layer 130 has a hemispherical shape as shown in FIGS. 3A and 3B , the separation distance of the unit pattern in the light extraction pattern (or the distance between the unit patterns) (d) for each light extraction As a graph showing the efficiency, the horizontal axis represents the separation distance (d) and the vertical axis represents the light extraction efficiency.

When the light extraction pattern of the insulating layer 130 is hemispherical as shown in FIGS. 3A and 3B , and the length L of the bottom surface is 4.5 μm and the height h is 1.5 μm in the unit pattern, the separation distance d ) of 0 μm to 3 μm, the obtained light extraction efficiencies are shown in Table 2 below.

Spacing (d) (μm) 0 0.5 1.0 1.5 2.0 2.5 3.0 Light extraction efficiency (%) 63 61.5 60.8 58.4 56.1 53.9 51.0

Referring to Table 2 and FIG. 10, when the separation distance d is 0 μm to 1 μm, it can be seen that the light extraction efficiency is 60% or more. In particular, it can be seen that when the separation distance d is 0 μm in the light extraction pattern of the insulating layer 130 , the light extraction efficiency is the best as 63%. This is because, as the number of unit patterns per unit area of the insulating layer 130 increases, the probability that diffuse reflection occurs by the light extraction pattern increases, and thus the degree of contribution of the pattern to light extraction increases.

In addition, when the light extraction pattern of the insulating layer 130 is hemispherical, the separation distance d between the unit patterns is 0 μm, the height h is 1.5 μm, and the length L of the bottom is 4.5 μm, in FIG. Comparing the light extraction efficiencies of the light emitting devices 100A, 100B, and 100C shown in FIGS. 1, 6 and 7 are shown in Table 3 below.

shape of light emitting element 100A 100B 100C Light extraction efficiency (%) 70 63 68

The light extraction efficiency of the light emitting device 100A is 70% when the refractive index of the insulating layer 130 is 1.6, and the light extraction efficiency of the light emitting device 100B is 63% when the refractive index of the conductive light transmitting layer 160 is 2.6. , the light extraction efficiency of the light emitting device 100C may be 68% when the refractive index of the doped layer 170 is 2.0. As such, it can be seen that the light extraction efficiency of the light emitting device 100A shown in FIG. 1 is the highest.

In addition, as shown in FIG. 6 , when the light emitting device 100C includes the doped layer 170 , the light extraction efficiency is higher than when the light extraction pattern is provided to the conductive light transmitting layer 160 , as shown in FIG. 7 . It can be seen that this is higher. This is because ZnO, which is the doped layer 170 , has superior transmittance and electrical conductivity in infrared and visible light compared to ITO, which is the conductive light-transmitting layer 160 . In addition, ZnO can be processed at a lower temperature than ITO and the raw material price is low. Accordingly, when the light emitting device 100C includes the doped layer 170 , the conductive light-transmitting layer 160 may be omitted.

In addition, as shown in FIG. 7 , when ZnO, which is the doped layer 160 , is doped with a second conductivity type dopant such as aluminum (Al), electrical conductivity may be further improved.

11 is a graph showing the light extraction efficiency 210 and the light transmittance 212 according to the thickness t of the conductive light transmitting layer 160 .

Referring to FIG. 1 , light extraction efficiency may be improved according to a distance D between the active layer 124 and the light extraction pattern of the insulating layer 130 . Here, the distance D corresponds to the distance from the boundary 125 between the active layer 124 and the second conductivity-type semiconductor layer 126 to the boundary between the light extraction pattern of the conductive light-transmitting layer 160 and the insulating layer 130 . do. To this end, instead of the distance D, the thickness t of the conductive light-transmitting layer 160 may be adjusted.

The refractive index of ITO as the conductive light transmitting layer 160 is 2.06, the light extraction pattern of the insulating layer 130 is hemispherical as illustrated in FIGS. 3A and 3B , and the length L of the bottom surface of the unit pattern is 4.5 μm When the height (h) of the hemispherical pattern is 1.5 µm and the separation distance (d) is 0 µm, the light extraction efficiency according to the change in the thickness (t) and the distance (D) of the conductive light-transmitting layer 160 is obtained. The comparison is shown in Table 4 below. Here, the transmittance is a value obtained when the wavelength of light emitted from the active layer 124 is 550 nm.

t (nm) One 3 5 7 10 20 30 D (nm) 201 203 205 207 210 220 230 Transmittance (%) 88 87 87 86 85 82 80 Light extraction efficiency (%) 62 73 73 73 73 62 66

11 and Table 4, the thickness (t) range of the conductive light-transmitting layer 160 that may be implemented with ITO may be determined based on light extraction efficiency. The thinner the thickness (t) of the conductive light-transmitting layer 160 is, the better the light extraction efficiency is, but when it is less than 3 nm, there may be disadvantages in sheet resistance increase and voltage increase due to the transmittance deviation between positions of the coating film and decrease in thickness. At this time, as the voltage increases, the amount of heat generated increases, thereby shortening the life of the product. In addition, when the thickness t of the conductive light-transmitting layer 160 exceeds 10 nm, transmittance of the conductive light-transmitting layer 160 may be lowered, thereby reducing light extraction efficiency. Accordingly, when the thickness t of the conductive light-transmitting layer 160 is 3 nm to 10 nm and the distance D is 203 nm to 210 nm, it can be seen that the light extraction efficiency is the best as 73%.

12 is a graph showing the transmittance for each thickness (t) of the conductive light-transmitting layer 160 according to the wavelength (λ) of light emitted from the active layer 124, wherein the horizontal axis indicates the wavelength (λ) and the vertical axis indicates the transmittance (transmittance) indicates.

Referring to FIG. 12 , even though the thickness t of the conductive light-transmitting layer 160 is the same, it can be seen that the transmittance varies according to the wavelength λ of the light. In addition, it can be seen that the transmittance varies according to the thickness t. Therefore, it can be seen that the maximum transmittance, that is, the maximum light extraction efficiency, can be obtained by optimally selecting the thickness t of the conductive light-transmitting layer 160 according to the wavelength λ of the light emitted from the active layer 124 . can

13 is a cross-sectional view of a light emitting device according to a comparative example.

In the case of the light emitting device according to the comparative example shown in FIG. 13 , unlike the light emitting device according to the embodiment shown in FIG. 1 , the insulating layer 30 and the reflective layer 40 do not have a light extraction pattern. In the case of the light emitting device according to the comparative example shown in FIG. 13 , the light emitted from the active layer 124 is totally reflected in the arrow direction 220 due to the difference in refractive index of each layer in the light emitting structure 120 and is trapped in the light emitting structure 120 . (Trap), it can be seen that the emission from the light emitting device is not possible.

On the other hand, in the case of the light emitting device 100A according to the embodiment shown in FIG. 1 , the light emitted from the active layer 124 is not totally internally reflected in the arrow direction 220 as shown in FIG. 13 and the insulating layer 130 . It can be seen that the light is scattered in the light extraction pattern of , and is emitted in the direction of the arrow 224 from the light emitting device 100A. Accordingly, the light extraction efficiency of the light emitting device 100A according to the embodiment may be improved. This is also the case for the light emitting devices 100B and 100C shown in FIGS. 6 and 7 . That is, by reducing the amount of light totally reflected inside the light emitting structure 120 , the probability that light is emitted from the light emitting devices 100A to 100C may increase. Accordingly, the light extraction efficiency expressed by Equation 1 below may be improved.

Here, N1 represents the number of photons emitted from the light emitting devices 100A to 100C into free space, and N2 represents the number of photons emitted from the active layer 124 .

Hereinafter, the light emitting device package 300 according to the embodiment will be described with reference to the accompanying drawings.

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

The light emitting device package 300 illustrated in FIG. 14 includes a light emitting device 100A, a package body 310 , first and second lead frames 322 and 324 , an insulating portion 326 , and first and It may include second pads 332 and 334 , first and second solder portions 342 and 344 , and a molding member 350 .

The package body 310 may form a cavity (C: Cavity). For example, as shown in FIG. 14 , the package body 310 may form a cavity C together with the first and second lead frames 322 and 324 . That is, the cavity C may be defined by the side surface 312 of the package body 310 and the respective upper surfaces 322A and 324A of the first and second lead frames 322 and 324 . However, the embodiment is not limited thereto. According to another embodiment, unlike shown in FIG. 14 , the cavity C may be formed with only the package body 310 . Alternatively, a barrier wall (not shown) may be disposed on the package body 310 having a flat upper surface, and a cavity may be defined by the barrier wall and the upper surface of the package body 310 . The package body 310 may be implemented with EMC (Epoxy Molding Compound) or the like, but the embodiment is not limited to the material of the package body 310 .

The light emitting device 100A may be disposed inside the cavity C formed in the package body 310 . The light emitting device package 300 shown in FIG. 14 is exemplified as including the light emitting device 100A shown in FIG. 1 , but the embodiment is not limited thereto. That is, the light emitting device package 300 according to another embodiment may include the light emitting devices 100B and 100C illustrated in FIG. 6 or 7 instead of the light emitting device 100A illustrated in FIG. 1 , and even in this case The following description is applicable. Since the light emitting device 100A shown in FIG. 14 is the same as the light emitting device 100A shown in FIG. 1 , the same reference numerals are used, and overlapping descriptions will be omitted.

The first pad 332 may penetrate the insulating layer 130 and may be electrically connected to the first conductivity-type semiconductor layer 122 through the first electrode 152 . In addition, the second pad 334 may penetrate the insulating layer 130 and may be electrically connected to the second conductive semiconductor layer 126 through the second electrode 154 , the reflective layer 140 , and the conductive transparent layer 160 . have. Each of the first and second pads 332 and 334 may include an electrode material.

The first and second lead frames 322 and 324 are formed in a first direction (eg, z-axis direction) and a second direction (eg, y-axis direction) perpendicular to the thickness direction of the light emitting structure 120 . They may be spaced apart from each other. In addition, the first lead frame 322 is electrically connected to the first pad 332 through the first solder portion 342 , and the second lead frame 324 is connected to the second lead frame 324 through the second solder portion 344 . It may be electrically connected to the pad 334 . To this end, each of the first and second lead frames 322 and 324 may be made of a conductive material, for example, a metal, and the embodiment depends on the type of material of each of the first and second lead frames 322 and 324 . not limited In order to electrically isolate the first and second lead frames 322 and 324 , an insulating part 326 may be disposed between the first and second lead frames 322 and 324 .

Also, when the package body 310 is made of a conductive material, for example, a metal material, the first and second lead frames 322 and 324 may be a part of the package body 310 . Even in this case, the package body 310 forming the first and second lead frames 322 and 324 may be electrically separated from each other by the insulating part 326 .

The first solder part 342 electrically connects the first lead frame 322 to the first conductivity-type semiconductor layer 122 through the first pad 332 . To this end, the first solder part 342 may be disposed between the first lead frame 322 and the first pad 332 to electrically connect them 322 and 332 to each other. The second solder portion 344 electrically connects the second lead frame 324 to the second conductivity-type semiconductor layer 126 through the second pad 334 . To this end, the second solder portion 344 may be disposed between the second lead frame 324 and the second pad 334 to electrically connect them 324 and 334 to each other. Each of the first and second solder parts 342 and 344 may be a solder paste or a solder ball.

As described above, the first and second solder portions 342 and 344 electrically connect the first and second conductivity-type semiconductor layers 122 and 126 to the first and second lead frames 322 and 324, respectively. This eliminates the need for wires. However, according to another embodiment, the first and second conductivity-type semiconductor layers 122 and 126 may be respectively connected to the first and second lead frames 322 and 324 using wires.

In addition, the molding member 350 may be filled in the cavity C to surround and protect the light emitting device 100A. The molding member 350 may be made of, for example, silicon (Si), and because it includes a phosphor, a wavelength of light emitted from the light emitting device 100A may be changed. The phosphor may include a phosphor that is a wavelength conversion means of any one of YAG-based, TAG-based, Silicate-based, Sulfide-based, and Nitride-based phosphors capable of converting light generated from the light emitting device 100A into white light. is not limited to the type of phosphor.

YAG and TAG-based fluorescent materials can be used by selecting from (Y, Tb, Lu, Sc, La, Gd, Sm)3(Al, Ga, In, Si, Fe)5(O, S)12:Ce, The silicate-based fluorescent material can be selected from (Sr, Ba, Ca, Mg)2SiO4: (Eu, F, Cl).

In addition, it is possible to select from (Ca,Sr)S:Eu, (Sr,Ca,Ba)(Al,Ga)2S4:Eu for sulfide-based phosphors, and for nitride-based phosphors, (Sr, Ca, Si, Al , O)N:Eu (e.g. CaAlSiN4:Eu β-SiAlON:Eu) or (Cax,My)(Si,Al)12(O,N)16 based on Ca-α SiAlON:Eu, where M is Eu, Tb , Yb, or Er at least one material, and can be used by selecting from among 0.05<(x+y)<0.3, 0.02<x<0.27 and 0.03<y<0.3, phosphor components.

As the red phosphor, a nitride-based phosphor including N (eg, CaAlSiN3:Eu) may be used. Such a nitride-based red phosphor has superior reliability to external environments, such as heat and moisture, as well as a lower risk of discoloration than a sulfide-based phosphor.

A plurality of light emitting device packages 300 according to the embodiment may be arrayed on a substrate, and optical members such as a light guide plate, a prism sheet, a diffusion sheet, etc. may be disposed on a light path of the light emitting device package 300 . The light emitting device package 300 , the substrate, and the optical member may function as a backlight unit.

In addition, the light emitting device package 300 according to the embodiment may be implemented as a display device, an indicator device, and a lighting device. Here, the display device includes a bottom cover, a reflecting plate disposed on the bottom cover, a light emitting module emitting light, a light guide plate disposed in front of the reflecting plate and guiding light emitted from the light emitting module in front of the light guide plate An optical sheet comprising prism sheets disposed thereon, a display panel disposed in front of the optical sheet, an image signal output circuit connected to the display panel and supplying an image signal to the display panel, and a color filter disposed in front of the display panel. may include Here, the light emitting module may include the light emitting device package 300 according to the embodiment. In addition, the bottom cover, the reflector, the light emitting module, the light guide plate, and the optical sheet may form a backlight unit.

In addition, the lighting device includes a light source module including a substrate and a light emitting device package 300 according to an embodiment, a heat sink for dissipating heat of the light source module, and processing or converting an electrical signal provided from the outside to provide the light source module It may include a power supply unit. For example, the lighting device may include a lamp, a head lamp, or a street lamp.

The head lamp is a light emitting module including a plurality of light emitting device packages 300 disposed on a substrate, a reflector that reflects light irradiated from the light emitting module in a predetermined direction, for example, forward, and light reflected by the reflector. It may include a lens that refracts forward, and a shade that blocks or reflects a portion of light reflected by the reflector and directed to the lens to form a light distribution pattern desired by a designer.

In the above, the embodiment has been mainly described, but this is only an example and does not limit the present invention, and those of ordinary skill in the art to which the present invention pertains are not exemplified above in the range that does not depart from the essential characteristics of the present embodiment. It will be appreciated that various modifications and applications are possible. For example, each component specifically shown in the embodiment may be implemented by modification. 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, 100C: light emitting element 110: substrate
112: pattern 120: light emitting structure
122: first conductivity type semiconductor layer 124: active layer
126: second conductivity type semiconductor layer 130, 130A: insulating layer
140: reflective layer 152: first electrode
154: second electrode 160: conductive light-transmitting layer
170: doped layer 300: light emitting device package
310: package body 322: first lead frame
324: second lead frame 326: insulation part
332: first pad 334: second pad
342: first solder part 344: second solder part
350: molding member

Claims (12)

Board;
a light emitting structure disposed under the substrate and including a first conductivity type semiconductor layer, an active layer, and a second conductivity type semiconductor layer;
an insulating layer disposed under the light emitting structure and having a light extraction pattern;
a reflective layer disposed between the light emitting structure and the insulating layer;
A first electrode that penetrates through the reflective layer, the second conductivity-type semiconductor layer, and the active layer, is connected to the first conductivity-type semiconductor layer, and is electrically insulated from the second conductivity-type semiconductor layer and the active layer by the insulating layer ; and
and a second electrode connected to the second conductivity type semiconductor layer through the insulating layer,
The light extraction pattern has a convex shape toward the active layer, and the convex shape has at least one three-dimensional shape of a polyhedral shape, a conical shape, or a hemispherical shape,
The height of the unit pattern in the hemispherical light extraction pattern is 1.2 μm to 1.8 μm,
In the light extraction pattern, the interval between unit patterns is 1 μm or less,
Further comprising a conductive light-transmitting layer disposed between the light emitting structure and the reflective layer,
The insulating layer is also disposed between the conductive light-transmitting layer and the reflective layer in the thickness direction of the light-emitting structure,
Further comprising a doping layer disposed between the conductive light-transmitting layer and the reflective layer,
The doped layer contains ZnO and is doped with a second conductivity type dopant,
The doped layer is not connected in a direction perpendicular to the thickness direction of the light emitting structure, but has a broken pattern. delete delete delete Board;
a light emitting structure disposed under the substrate and including a first conductivity type semiconductor layer, an active layer, and a second conductivity type semiconductor layer;
an insulating layer disposed under the light emitting structure and having a light extraction pattern;
a reflective layer disposed between the light emitting structure and the insulating layer;
A first electrode that penetrates through the reflective layer, the second conductivity-type semiconductor layer, and the active layer, is connected to the first conductivity-type semiconductor layer, and is electrically insulated from the second conductivity-type semiconductor layer and the active layer by the insulating layer ; and
and a second electrode connected to the second conductivity type semiconductor layer through the insulating layer,
The light extraction pattern has a convex shape toward the active layer, and the convex shape has at least one three-dimensional shape of a polyhedral shape, a conical shape, or a hemispherical shape,
The height of the unit pattern in the hemispherical light extraction pattern is 1.2 μm to 1.8 μm,
In the light extraction pattern, the interval between unit patterns is 1 μm or less,
Further comprising a conductive light-transmitting layer disposed between the light emitting structure and the reflective layer,
The insulating layer is also disposed between the conductive light-transmitting layer and the reflective layer in the thickness direction of the light-emitting structure,
The reflective layer has a pattern of the same shape as the light extraction pattern of the insulating layer,
The conductive light-emitting layer is a light emitting device having the same shape as the light extraction pattern of the insulating layer. delete delete delete delete The method according to claim 1 or 5, wherein the conductive light-transmitting layer has a thickness of 3 nm to 10 nm,
A distance from the boundary between the active layer and the second conductivity-type semiconductor layer to the boundary between the conductive light-transmitting layer and the light extraction pattern is 203 nm to 210 nm. delete delete

Images