KR102408617B1 - Light emitting device package, and light emitting apparatus including the package - Google Patents

Abstract

The light emitting device package of the embodiment includes a substrate and a light emitting structure disposed under the substrate, the light emitting structure including a first conductivity type semiconductor layer, an active layer, and a second conductivity type semiconductor layer, and a penetration through the second conductivity type semiconductor layer and the active layer The first electrode buried in the hole and connected to the first conductivity-type semiconductor layer, the first passivation layer disposed between the first electrode and the light emitting structure, and the first electrode are electrically spaced apart from each other and connected to the second conductivity-type semiconductor layer It includes two electrodes, wherein the first electrode is disposed to be bent downward from the sidewall of the light emitting structure with the first passivation layer interposed therebetween.

Description

Light emitting device package and light emitting device including the same

The embodiment relates to a light emitting device package and a light emitting device including the same.

A light emitting diode (LED) is a type of semiconductor device that converts electricity into infrared or light by using characteristics of a compound semiconductor to send and receive signals or 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 Various studies are being conducted to improve the reliability of a conventional light emitting device package including such a light emitting diode.

The embodiment provides a light emitting device package having an improved electrode structure and a light emitting device including the same.

A light emitting device package 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; a first electrode buried in a through hole passing through the second conductivity type semiconductor layer and the active layer and connected to the first conductivity type semiconductor layer; a first passivation layer disposed between the first electrode and the light emitting structure; and a second electrode electrically spaced apart from the first electrode and connected to the second conductivity-type semiconductor layer, wherein the first electrode has the first passivation layer interposed therebetween, and the light emission from the sidewall of the light emitting structure The structure may be bent down and disposed.

For example, the first passivation layer may include: a 1-1 passivation layer disposed between a sidewall of the light emitting structure exposed in the through hole and the first electrode; and a 1-2 th passivation layer extending from the 1-1 passivation layer to an outer side of a lower surface of the light emitting structure.

For example, the first passivation layer may further include a 1-3 th passivation layer bent and extended from the 1-1 passivation layer in the through hole and disposed under the first conductivity-type semiconductor layer.

For example, the first electrode is buried in the through hole and connected to the first conductivity type semiconductor layer, and faces the second conductivity type semiconductor layer and the active layer with the 1-1 passivation layer therebetween. 1-1 electrode; a first-second electrode disposed under the first-first electrode; and 1-3 electrodes extending from the 1-2 electrodes and electrically spaced apart from the lower surface of the second conductivity-type semiconductor layer with the 1-2 passivation layer interposed therebetween.

For example, the thickness of the 1-3 electrodes disposed under the 1-2 passivation layer may be the same as the depth of the through hole.

For example, the 1-3 th electrodes, the 1-2 th passivation layer, and the light emitting structure may overlap in a thickness direction of the light emitting structure.

For example, the light emitting device package may further include a second passivation layer disposed to surround the first electrode together with the 1-2 passivation layer while exposing at least a portion of a lower surface of the first electrode.

For example, the second passivation layer may be disposed to cover the 1-2 and 1-3 electrodes together with the 1-2 passivation layer while exposing a portion of the lower surface of the 1-1 electrode. .

For example, the first passivation layer and the second passivation layer may include the same material.

For example, the first electrode may include at least one of Cr, Al, Ni, Cu, and Ti.

For example, the first electrode may include Cr/Al/Ni/Cu/Ni/Ti sequentially stacked under the first conductivity-type semiconductor layer in the through hole.

For example, the second electrode may include a material having light reflection properties.

For example, the light emitting device package may further include a light-transmitting electrode layer disposed between the second electrode and the second conductivity-type semiconductor layer.

For example, the light emitting device package may include a first pad connected to the first electrode; a second pad connected to the second electrode; and a third passivation layer disposed between the first pad and the second electrode and disposed between the second pad and the first electrode.

For example, the third passivation layer may include a diffuse Bragg reflective layer.

For example, the overlapping width of the 1-2 passivation layer and the 1-3 electrodes in the thickness direction of the light emitting structure may be 2 μm or more.

A light emitting device according to another embodiment may include the light emitting device package.

The light emitting device package and the light emitting device including the same according to the embodiment do not have a relatively higher driving voltage than the comparative example, have improved light emitting efficiency, and have no low current failure.

1 is a plan view of a light emitting device package according to an embodiment.
FIG. 2 is a cross-sectional view of the light emitting device package shown in FIG. 1 .
FIG. 3 is an enlarged cross-sectional view of part 'A' shown in FIG. 2 .
4 is a cross-sectional view showing an enlarged view of part 'A' shown in FIG. 2 according to another embodiment.
5A to 5F are process plan views illustrating a method of manufacturing the light emitting device package shown in FIGS. 1 and 2 .
6A to 6H are cross-sectional views illustrating a method of manufacturing the light emitting device package shown in FIGS. 1 and 2 .
FIG. 7 is an enlarged cross-sectional view of only a portion corresponding to part 'A' of the light emitting device package according to the embodiment shown in FIG. 2 in the light emitting device package according to the comparative example.
8 is a local cross-sectional view illustrating a process of forming an n-type electrode in the light emitting device package according to the comparative example shown in FIG. 7 .

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, 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 below. The embodiments of the present invention are provided in order to more completely explain the present invention to those of ordinary skill in the art.

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

Also, as used hereinafter, relational terms such as “first” and “second,” “top/top/top” and “bottom/bottom/bottom” refer to any physical or logical relationship between such entities or elements or It may be used only to distinguish one entity or element from another, without requiring or implying an order.

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 fully reflect the actual size.

1 is a plan view of a light emitting device package 100 according to an embodiment, and FIG. 2 is a cross-sectional view of the light emitting device package 100 shown in FIG. 1 . For ease of understanding, the through hole TH shown in FIG. 6B is indicated by a dotted line in FIG. 2 .

1 and 2 , the light emitting device package 100 according to the embodiment includes a substrate 110 , a package body (or body) 112 , a light emitting structure 120 , first, second and third Passivation layers 130A, 150, 170, first and second electrodes 140 and 164, light-transmitting electrode layer 162, first and second pads 182 and 184, first and second solder parts 186 and 188 , first and second lead frames 192 and 194 , an insulating portion 196 , and a molding member 198 may be included.

The substrate 110 shown in FIG. 2 , the light emitting structure 120 , the first, second and third passivation layers 130A, 150 , and 170 , the first and second electrodes 140 and 164 , and the light-transmitting electrode layer 162 . ), the first and second pads 182 and 184 correspond to a cross-sectional view taken along the line I-I' shown in FIG. 1 .

For convenience of description, the package body 112, the first and second solder parts 186 and 188, the first and second lead frames 192 and 194, the insulating part 196 and the molding member ( 198) is not shown in FIG. 1 and is omitted.

The light emitting structure 120 may be disposed under the substrate 110 . 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, but in the embodiment, the substrate 110 ) 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.

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 may be disposed under the substrate 110 . The first conductivity type semiconductor layer 122 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 may be disposed between the first conductivity-type semiconductor layer 122 and the second conductivity-type semiconductor layer 126 . In the active layer 124, electrons (or holes) injected through the first conductivity type semiconductor layer 122 and holes (or electrons) injected through the second conductivity type semiconductor layer 126 meet each other, and the active layer ( 124) is a layer that emits light with energy determined by the intrinsic energy band of the material. 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, and 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 cladding 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.

Also, according to an embodiment, the active layer 124 may emit light in an ultraviolet wavelength band. Here, the ultraviolet wavelength band means a wavelength band of 100 nm to 400 nm. In particular, the active layer 124 may emit light in a wavelength band of 100 nm to 280 nm. However, the embodiment is not limited to a wavelength band of light emitted from the active layer 124 .

The second conductivity type semiconductor layer 126 may be disposed under the active layer 124 . The second conductivity-type semiconductor layer 126 may be formed of a semiconductor compound, and may be implemented as 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.

The first electrode 140 may be buried in the through hole TH and may be electrically connected to the first conductivity type semiconductor layer 122 . As illustrated in FIG. 6B , the through hole TH passes through the second conductivity type semiconductor layer 126 and the active layer 124 , so it is called a through hole, but is a kind of blind hole.

Since the first electrode 140 includes a material in ohmic contact to perform an ohmic role, a separate ohmic layer (not shown) may not need to be disposed, and a separate ohmic layer may be disposed above or below the first electrode 140 . may be placed in

Meanwhile, the first passivation layer 130A is disposed between the first electrode 140 and the light emitting structure 120 . Specifically, the first passivation layer 130A is formed between the first electrode 140 and the sidewall 120 - 1 of the light emitting structure 120 and the lower surface of the first electrode 140 and the light emitting structure 120 , 120 - 2) can be placed in between.

In this case, the first electrode 140 may be disposed to be bent downward from the sidewall 120 - 1 of the light emitting structure 120 with the first passivation layer 130A interposed therebetween.

FIG. 3 is an enlarged cross-sectional view of part 'A' shown in FIG. 2 .

According to an embodiment, as illustrated in FIG. 3 , the first passivation layer 130A may include a 1-1 passivation layer 132 and a 1-2 th passivation layer 134 . The 1-1 passivation layer 132 may be disposed between the sidewall 120 - 1 of the light emitting structure 120 exposed through the through hole TH and the first electrode 140 . The 1-2-th passivation layer 134 is disposed extending from the 1-1 passivation layer 132 to the outer side 120-2 of the lower surface of the light-emitting structure 120 in a direction crossing the thickness direction of the light-emitting structure 120 . can be Here, the direction crossing the thickness direction of the light emitting structure 120 (hereinafter, the cross direction) may be, for example, a direction perpendicular to the thickness direction of the light emitting structure 120 (hereinafter, the vertical direction).

4 is a cross-sectional view according to another embodiment (A2) showing an enlarged view of the portion 'A' shown in FIG. 2 .

According to another embodiment, as illustrated in FIG. 4 , the first passivation layer 130B includes the 1-1 and 1-2 passivation layers 132 and 134 as well as the 1-3 passivation layer 136 . may include more. Here, the 1-1 and 1-2 passivation layers 132 and 134 are as shown in FIG. 3 . The 1-3 th passivation layer 136 may be bent and extended in a cross direction from the 1-1 th passivation layer 132 in the through hole TH to be disposed under the first conductivity type semiconductor layer 122 .

Meanwhile, referring to FIGS. 3 and 4 , the first electrode 140 may include a 1-1 electrode 142 , a 1-2 electrode 144 , and a 1-3 electrode 146 .

The first-first electrode 142 may be buried in the through hole TH to be connected to the first conductivity-type semiconductor layer 122 . In addition, the 1-1 electrode 142 may face the second conductivity-type semiconductor layer 126 and the active layer 124 with the 1-1 passivation layer 132 interposed therebetween and may be electrically spaced apart from each other. That is, the 1-1 passivation layer 132 is disposed between the 1-1 electrode 142 and the second conductivity type semiconductor layer 126 , and between the 1-1 electrode 142 and the active layer 124 . A 1-1 passivation layer 132 may be disposed.

The 1-2 th electrode 144 may be disposed under the 1-1 th electrode 142 .

The 1-3 electrodes 146 extend in a crossing direction from the 1-2 electrodes 144 , and the lower surface 126 of the second conductivity type semiconductor layer 126 with the 1-2 passivation layer 134 interposed therebetween. -1) and may be electrically separated from each other. That is, the 1-3 th electrode 146 , the 1-2 th passivation layer 134 , and the light emitting structure 120 may overlap in the thickness direction of the light emitting structure 120 .

Also, a thickness T of the 1-3 first electrodes 146 disposed under the 1-2 passivation layer 134 may be the same as a depth D of the through hole TH.

In addition, in the first electrode 140 shown in FIGS. 3 and 4 , the 1-3 electrodes 146 are at a predetermined angle θ with respect to the lower surface 134-2 of the 1-2 passivation layer 134 . It may be formed to be inclined. This is described below in more detail in FIG. 6D .

Meanwhile, the second passivation layer 150 covers the first electrode 140 together with the 1-2 passivation layer 134 while exposing at least a portion 144 - 1 of the lower surface of the first electrode 140 . can be placed. That is, the second passivation layer 150 exposes a portion 144-1 of the lower surface of the 1-2 electrode 144, and together with the 1-2 passivation layer 134, the 1-2 electrode 144 and It may be disposed to surround the 1-3 th electrode 146 .

In addition, the above-described first passivation layers 130A and 130B and the second passivation layer 150 may include the same material.

In addition, in the first passivation layer 130A shown in FIG. 3 , the end 134-1 of the 1-2 passivation layer 134 and the side 150-1 of the second passivation layer 150 to be described later are mutually It may be formed to be inclined at the same angle. That is, the second passivation layer 150 shown in FIG. 3 is disposed under the lower portion 134-2 of the 1-2 passivation layer 134, but the end 134 of the 1-2 passivation layer 134. -1) is not placed.

On the other hand, the second passivation layer 150 shown in FIG. 4 is disposed under the lower portion 134-2 of the 1-2 passivation layer 134 as well as an end of the 1-2 passivation layer 134 . It can also be placed next to (134-1).

As such, except that the shapes of the first passivation layers 130A and 130B and the second passivation layer 150 are different, a cross-sectional view of the embodiment A1 shown in FIG. 3 is another embodiment shown in FIG. 4 . It is the same as the cross-sectional view by (A2). Therefore, in the embodiment (A2) shown in FIG. 4, a description of the overlapping part with the embodiment (A1) shown in FIG. 3 will be omitted.

Meanwhile, the first electrode 140 and the second electrode 164 are electrically spaced apart from each other by the first passivation layers 130A and 130B, and the second electrode 164 is connected to the second conductivity type semiconductor layer 126 and may be electrically connected.

In addition, the second electrode 164 may have an ohmic characteristic and may include a material in ohmic contact with the second conductivity-type semiconductor layer 126 . If the second electrode 164 performs an ohmic role, a separate ohmic layer (not shown) may not be formed.

In addition, the light-transmitting electrode layer 162 may be disposed between the second electrode 164 and the second conductivity-type semiconductor layer 126 . The light transmitting electrode layer 162 may be disposed to improve electrical characteristics of the second conductivity type semiconductor layer 126 . The light transmitting electrode layer 162 may be a transparent conductive oxide (TCO). For example, the light transmitting electrode layer 162 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 ( of 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, but is not limited to these materials.

Since the light emitting device package 100 illustrated in FIGS. 1 and 2 has a flip chip bonding structure, the light emitted from the active layer 124 is transmitted to the first electrode 140 and the first conductivity type semiconductor layer ( 122) and the substrate 110 may be emitted. To this end, the first electrode 140 , the first conductivity-type semiconductor layer 122 , and the substrate 110 may be formed of a material having light transmittance. In this case, the second conductivity-type semiconductor layer 126 and the second electrode 164 may be made of a material having a light transmittance or non-transmission property or a material having a reflection property, but the embodiment may not be limited to a specific material. For example, the second electrode 164 may include a material having light reflection characteristics to serve as a reflective layer.

The first and second electrodes 140 and 164 may be formed of any material that can be grown in good quality on each of the first and second conductivity-type semiconductor layers 122 and 126 . For example, each of the first and second electrodes 140 and 164 may be formed of a metal, Cr, Cu, Ti, Ag, Ni, Al, Rh, Pd, Ir, Ru, Mg, Zn, Pt, Au, Hf and optional combinations thereof, for example Cr, Al, Ni, Cu and Ti.

For example, the first electrode 140 may include Cr/Al/Ni/Cu/Ni/Ti sequentially stacked under the first conductivity-type semiconductor layer 122 in the through hole TH. That is, the first electrode 140 has a Cr layer disposed under the first conductivity type semiconductor layer 122 , an Al layer disposed under the Cr layer, a Ni layer disposed under the Al layer, and Cu disposed under the Ni layer. layer, a Ni layer disposed under the Cu layer, and a Ti layer disposed under the Ni layer.

Meanwhile, the first pad 182 may be electrically connected to the first electrode 140 , and the second pad 184 may be electrically connected to the second electrode 164 .

The third passivation layer 170 is disposed between the first pad 182 and the second electrode 164 to electrically separate the first pad 182 and the second electrode 164 from each other. In addition, the third passivation layer 170 is disposed between the second pad 184 and the first electrode 140 to electrically separate the second pad 184 from the first electrode 140 . can

As described above, the first and second pads 182 and 184 are electrically spaced apart from each other. Each of the first pad 182 and the second pad 184 may include a metal material having electrical conductivity, and may include the same or different material as the material of each of the first and second electrodes 140 and 164 . have.

Also, the third passivation layer 170 may include a distributed Bragg reflector (DBR). In this case, the third passivation layer 170 may perform both an insulating function and a reflective function.

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, 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.

When the second electrode 164 includes a reflective material, it is emitted from the active layer 124 and proceeds downward toward the first and second lead frames 192 and 194 without proceeding upward toward the substrate 110 . As light is reflected by the second electrode 164 and travels upward, the light extraction efficiency of the light emitting device package 100 may be improved.

In addition, when the third passivation layer 170 is implemented as a dispersed Bragg reflective layer, the first and second lead frames ( As light traveling downward toward 192 and 194 is reflected by the third passivation layer 170 and travels upward, light extraction efficiency of the light emitting device package 100 may be further improved.

Meanwhile, the first and second solder portions 186 and 188 may be electrically connected to the first and second pads 182 and 184 , respectively. The first solder unit 186 may be electrically connected to the first lead frame 192 , and the second solder unit 188 may be electrically connected to the second lead frame 194 . That is, the first solder portion 186 is disposed between the first lead frame 192 and the first pad 182 to electrically connect the 192 and 182 to each other, and the second solder portion 188 is It is disposed between the second lead frame 194 and the second pad 184 to electrically connect them 194 and 184 to each other.

The above-described first and second solder portions 186 and 188 connect the first and second conductivity-type semiconductor layers 122 and 126 through the first and second pads 182 and 184 to the first and second lead frames. Electrically connected to (192, 194) respectively, it is possible to eliminate the need for a wire. 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 192 and 194 using wires.

Also, the first solder portion 186 and the second solder portion 188 may be omitted. In this case, the first pad 182 may function as the first solder unit 186 , and the second pad 184 may function as the second solder unit 188 . When the first solder portion 186 and the second solder portion 188 are omitted, the first pad 182 is directly connected to the first lead frame 192 , and the second pad 184 is connected to the second lead frame (194) can be linked directly.

Each of the first solder part 186 and the second solder part 188 may be a solder paste or a solder ball.

The first and second lead frames 192 and 194 may be disposed to be spaced apart from each other in an intersecting direction.

Each of the first and second lead frames 192 and 194 may be made of a conductive material, for example, metal, and the embodiment is not limited to the type of each material of the first and second lead frames 192 and 194 . In order to electrically isolate the first and second lead frames 192 and 194 , an insulating part 196 may be disposed between the first and second lead frames 192 and 194 .

Each of the insulating portion 196 as well as the first passivation layers 130A and 130B and the second passivation layer 150 is SiO ₂ , TiO ₂ , ZrO ₂ , Si ₃ N ₄ , Al ₂ O ₃ , or MgF ₂ At least one of One insulating material may be included, but embodiments are not limited to specific materials of the first passivation layers 130A and 130B, the second passivation layer 150 and the insulating part 196 .

In addition, when the package body 112 is made of a conductive material, for example, a metal material, the first and second lead frames 192 and 194 may be a part of the package body 112 . Even in this case, the package body 112 forming the first and second lead frames 192 and 194 may be electrically separated from each other by the insulating part 196 .

The package body 112 may form a cavity (C: Cavity). For example, as illustrated in FIG. 2 , the package body 112 may form a cavity C together with the first and second lead frames 192 and 194 . That is, the cavity C may be defined by the inner surface of the package body 112 and the upper surfaces of the first and second lead frames 192 and 194 . However, the embodiment is not limited thereto. According to another embodiment, unlike illustrated in FIG. 2 , the cavity C may be formed with only the package body 112 . Alternatively, a barrier wall (not shown) may be disposed on the package body 112 having a flat upper surface, and a cavity may be defined by the barrier wall and the upper surface of the package body 112 . The package body 112 may be implemented with EMC (Epoxy Molding Compound), etc., but the embodiment is not limited to the material of the package body 112 .

The molding member 198 may surround and protect the substrate 110 , the third passivation layer 170 , the first and second pads 182 and 184 , and the first and second solder portions 186 and 188 . . The molding member 198 may be made of, for example, silicon (Si), and because it includes a phosphor, the wavelength of light emitted from the active layer 124 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 in the active layer 124 into white light. It 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, the Sulfide-based fluorescent material can be selected from (Ca,Sr)S:Eu, (Sr,Ca,Ba)(Al,Ga)2S4:Eu, and the Nitride-based fluorescent material is (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, and has a lower risk of discoloration than a sulfide-based phosphor.

In addition, in the case of FIG. 1 , each of the first and second pads 182 and 184 is illustrated as having a rectangular planar shape, but the embodiment is not limited thereto. For example, according to another embodiment, each of the first and second pads 182 and 184 may have an elliptical planar shape or various polygonal planar shapes such as a triangle or a pentagon.

Hereinafter, a method of manufacturing the light emitting device package 100 shown in FIGS. 1 and 2 will be described with reference to FIGS. 5A to 5F and 6A to 6H .

5A to 5F are process plan views illustrating a method of manufacturing the light emitting device package 100 illustrated in FIGS. 1 and 2 . For ease of understanding, in each of FIGS. 5B to 5F , the boundary between the layers in the previous process is indicated by a dotted line.

6A to 6H are cross-sectional views illustrating a method of manufacturing the light emitting device package 100 illustrated in FIGS. 1 and 2 .

Referring to FIG. 6A , the light emitting structure 120 is formed on the substrate 110 . The substrate 110 may be formed of a conductive material or a non-conductive material. For example, the substrate 110 may be formed of at least one of sapphire (Al ₂ 0 ₃ ), GaN, SiC, ZnO, GaP, InP, Ga ₂ 0 ₃ , GaAs and Si, but in the embodiment, the substrate ( 110) is not limited to the forming material.

The light emitting structure 120 may be formed by sequentially stacking the first conductivity type semiconductor layer 122 , the active layer 124 , and the second conductivity type semiconductor layer 126 on the substrate 110 .

That is, first, the 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 of a semiconductor material. The first conductivity type semiconductor layer 122 may be formed of any one or more of GaN, InN, AlN, InGaN, AlGaN, InAlGaN, AlInN, AlGaAs, InGaAs, AlInGaAs, GaP, AlGaP, InGaP, AlInGaP, and InP.

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, and 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 .

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, and 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 a semiconductor material having a composition formula of In _x Al _y Ga _{1 -x- y} N (0≤x≤1, 0≤y≤1, 0≤x+y≤1) can be formed with 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.

Thereafter, referring to FIGS. 5A and 6B , the second conductivity type semiconductor layer 126 , the active layer 124 , and a portion of the first conductivity type semiconductor layer 122 are mesa-etched to form a first conductivity type semiconductor A through hole TH exposing the layer 122 is formed.

In addition, although it is illustrated that the number of through holes TH is six in FIGS. 1 and 5A , the embodiment is not limited thereto. That is, the number of through-holes TH may be greater or less than six.

Thereafter, referring to FIGS. 5B and 6C , the first passivation is performed to surround the light emitting structure 120 including the sidewall 120 - 1 while exposing the first conductivity type semiconductor layer 122 of the through hole TH. A layer 130A is formed.

If it is desired to form the light emitting device package shown in FIG. 4 instead of FIG. 3 , the first conductivity type semiconductor layer 122 that is exposed and extended from the sidewall 120 - 1 of the light emitting structure 120 in the cross direction The first passivation layer 130A may be formed up to the upper portion.

Thereafter, referring to FIGS. 5C and 6D , a mask 300 exposing the through hole TH and the 1-2 passivation layer 134 disposed on the light emitting structure 120 to form the first electrode 140 . ) to form For example, a photoresist (PR) pattern may be formed on the light emitting structure 120 as the mask 30 to form the first electrode 140 .

Thereafter, using the photoresistor (PR) pattern as the mask 300 , a material for forming the first electrode 140 is deposited to fill the through hole TH and the second passivation layer 134 is formed. One electrode 140 is formed. As such, when the first electrode 140 is also formed on the 1-2 passivation layer 134 , the first electrode 140 may be gap-filled in the through hole TH. Thereafter, the photoresistor PR pattern is removed.

Thereafter, referring to FIGS. 5D and 6E , a second passivation layer 150 is formed on the resultant product from which the mask 300 is removed. Thereafter, the first and second passivation layers 130A and 150 are simultaneously etched to expose the second conductivity-type semiconductor layer 126 , while at least a portion of the upper surface of the first electrode 140 is exposed. The first and second passivation layers 130A and 150 may be formed of the same material or different materials. Each of the first and second passivation layers 130A and 150 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 .

According to another embodiment, as shown in FIGS. 6c and 6d, instead of forming the first passivation layer 130A on the entire surface of the light emitting structure 120, the light emitting structure 120 as shown in FIG. 4 The second conductivity type semiconductor layer 126 may be exposed by forming the first passivation layer 130B only up to the sidewall 120 - 1 of the light emitting structure 120 and the upper edge 126 - 2 of the light emitting structure 120 . Subsequently, after forming the second passivation layer 150 on the second conductivity-type semiconductor layer 126 exposed by the first passivation layer 130B and the first passivation layer 130B, it is shown in FIG. 4 . The second passivation layer 150 may be etched in the structure as described above to expose the second conductivity type semiconductor layer 126 and the first electrode 140 .

Thereafter, referring to FIGS. 5E and 6F , a light-transmitting electrode layer 162 is formed on the second conductivity-type semiconductor layer 126 exposed by the first and second passivation layers 130A and 150 , and the light-transmitting electrode layer 162 is formed. ) may be formed on the second electrode 164 . The light transmitting electrode layer 162 may be formed of a transparent conductive oxide (TCO). For example, the transparent electrode layer 162 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, but is not limited to these materials.

For example, each of the first and second electrodes 140 and 164 may be formed of a metal, Cr, Cu, Ti, Ag, Ni, Al, Rh, Pd, Ir, Ru, Mg, Zn, Pt, Au, Hf and optional combinations thereof, for example Cr, Al, Ni, Cu and Ti.

Thereafter, referring to FIGS. 5F and 6G , the third passivation layer 170 may be formed while exposing portions to be connected to the first and second pads 182 and 184 in the first and second electrodes 140 and 164 . can The third passivation layer 170 may be implemented as a diffuse Bragg reflective layer, but the embodiment is not limited thereto.

Thereafter, referring to FIG. 6H , a first pad 182 is formed on the first electrode 140 exposed by the third passivation layer 170 , and a second pad 184 is formed on the second electrode 164 . to form Each of the first and second pads 182 may be formed of a metallic material having electrical conductivity, and may be formed of the same or different material as that of each of the first and second electrodes 140 and 164 .

7 is an enlarged cross-sectional view of a portion (B) corresponding to a portion 'A' of the light emitting device package 100 according to the embodiment shown in FIG. 2 in the light emitting device package according to the comparative example.

8 is a local cross-sectional view illustrating a process of forming the n-type electrode 40 in the light emitting device package according to the comparative example shown in FIG. 7 , in the manufacturing process of the light emitting device package 100 according to the embodiment. It can be compared with the process shown in 6d.

The light emitting device package according to the comparative example shown in FIGS. 7 and 8 may include a substrate 10 , a light emitting structure 20 , an insulating layer 30 , and an n-type electrode 40 . The light emitting structure 20 includes an n-type semiconductor layer 22 , an active layer 24 , and a p-type semiconductor layer 26 .

The substrate 10, the n-type semiconductor layer 22, the active layer 24, the p-type semiconductor layer 26, the insulating layer 30 and the n-type electrode 40 shown in FIGS. 7 and 8 are shown in FIG. 2, 3 and 4, respectively, the substrate 110, the first conductivity type semiconductor layer 122, the active layer 124, the second conductivity type semiconductor layer 126, the first passivation layers (130A, 130B) and Each of the electrodes 140 may be compared.

The n-type electrode 40 is buried in a through hole passing through the p-type semiconductor layer 22 and the active layer 24 and is electrically connected to the n-type semiconductor layer 22 .

In this case, the insulating layer 30 is disposed between the n-type electrode 40 and the p-type semiconductor layer 26 as well as the insulating layer 30 is disposed between the n-type electrode 40 and the active layer 24 .

In order to form the n-type electrode 40 of the light emitting device package shown in FIG. 7 , as shown in FIG. 8 , a photoresist pattern 40 is formed on the p-type semiconductor layer 26 . In this case, the photoresist pattern 40 exposes only the through hole and does not expose the insulating layer 30 disposed on the light emitting structure 20 . Further, the opening of the photoresist pattern 40 is inclined downward. Accordingly, when the n-type electrode 40 is deposited using the photoresist pattern 40 , a gapfill of the n-type electrode 40 is not performed, and the n-type electrode 40 and the insulating layer 30 are not formed. The occurrence of a gap (G:Gap) is inevitable. For this reason, the driving voltage of the light emitting device package according to the comparative example may increase, luminous efficiency may decrease, and a low current failure may be caused.

On the other hand, in the case of the light emitting device package 100 according to the embodiment shown in FIGS. 2 to 4 , as shown in FIG. 6D , the first electrode 140 is not only buried in the through hole TH but also a light emitting structure The first and second passivation layers 134 disposed on the 120 are bent in the cross direction to extend and extend. Accordingly, the first electrode 140 may be gap-filled without the gap G as shown in FIGS. 7 and 8 . For this reason, compared to the light emitting device package according to the comparative example, the driving voltage of the light emitting device package 100 according to the embodiment does not increase, luminous efficiency is improved, and low current failure can be prevented.

When the overlapping width of the 1-2 th passivation layer 134 in the thickness direction of the 1-3 th electrode 146 and the light emitting structure 120 is 2 μm or more, the gap fill of the first electrode 140 may be guaranteed. .

A plurality of light emitting device packages according to the embodiment may be arranged 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. Such a light emitting device package, a substrate, and an optical member may function as a backlight unit.

In addition, the light emitting device package according to the embodiment may be included in a light emitting device such as a display device, an indicator device, a lighting device, and the like.

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 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 according to an embodiment, a heat sink for dissipating heat of the light source module, and a power supply unit that processes or converts an electrical signal received from the outside and provides the light source module to the light source module may include For example, the lighting device may include a lamp, a head lamp, or a street lamp.

The head lamp includes a light emitting module including light emitting device packages disposed on a substrate, a reflector that reflects light emitted from the light emitting module in a predetermined direction, for example, forward, and a lens that refracts light reflected by the reflector 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 the 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 a range that does not depart from the essential characteristics of the present embodiment. It can be seen that various modifications and applications are possible. For example, each component specifically shown in the embodiment can 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.

100: light emitting device package 110: substrate
112: body 120: light emitting structure
122: first conductivity type semiconductor layer 124: active layer
126: second conductivity type semiconductor layer 130A, 130B: first passivation layer
132: 1-1 passivation layer 134: 1-2 passivation layer
136: 1-3 passivation layer 140: first electrode
142: 1-1 electrode 144: 1-2 electrode
146: first 1-3 electrode 150: second passivation layer
162: light transmitting electrode layer 164: second electrode
170: third passivation layer 182: first pad
184: second pad 186: first solder unit
188: second solder portion 192: first lead frame
194: second lead frame 196: insulation
198: molding member 300: mask

Claims (17)

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;
a first electrode buried in a through hole passing through the second conductivity type semiconductor layer and the active layer and connected to the first conductivity type semiconductor layer;
a first passivation layer disposed between the first electrode and the light emitting structure;
a second electrode electrically spaced apart from the first electrode and connected to the second conductivity-type semiconductor layer;
a second passivation layer disposed to surround the first electrode together with the first passivation layer while exposing at least a portion of a lower surface of the first electrode; and
a third passivation layer disposed to surround at least a portion of the second passivation layer and the second electrode, one end connected to the at least a portion of the first electrode and the other end connected to a lower surface of the second electrode;
A light emitting device package comprising a. According to claim 1, wherein the first passivation layer
a 1-1 passivation layer disposed between the sidewall of the light emitting structure exposed in the through hole and the first electrode; and
A light emitting device package including a 1-2 th passivation layer extending from the 1-1 passivation layer to the outer side of the lower surface of the light emitting structure. The method of claim 2, wherein the first passivation layer is
The light emitting device package further comprising: a 1-3 passivation layer bent from the 1-1 passivation layer in the through hole and disposed under the first conductivity-type semiconductor layer. The method of claim 2, wherein the first electrode
a 1-1 electrode buried in the through hole and connected to the first conductivity type semiconductor layer and facing the second conductivity type semiconductor layer and the active layer with the 1-1 passivation layer interposed therebetween;
a first-second electrode disposed under the first-first electrode; and
and a first 1-3 electrode extending from the 1-2 electrode and electrically spaced apart from a lower surface of the second conductivity-type semiconductor layer with the 1-2 passivation layer interposed therebetween. The light emitting device package of claim 4 , wherein a thickness of the 1-3 electrodes disposed under the 1-2 passivation layer is the same as a depth of the through hole. The light emitting device package of claim 4 , wherein the 1-3 electrodes, the 1-2 passivation layer, and the light emitting structure overlap in a thickness direction of the light emitting structure. The light emitting device package according to any one of claims 1 to 6, wherein the lower surface of the first electrode has a cavity in which one end of the second passivation layer and one end of the third passivation layer are disposed. The method of claim 7, wherein the second passivation layer is disposed to surround the 1-2 and 1-3 electrodes together with the 1-2 passivation layer while exposing a portion of a lower surface of the 1-1 electrode light emitting device package. The light emitting device package of claim 7 , wherein the first passivation layer and the second passivation layer include the same material. The light emitting device package of claim 1 , wherein the first electrode includes at least one of Cr, Al, Ni, Cu, and Ti. The light emitting device package of claim 10 , wherein the first electrode includes Cr/Al/Ni/Cu/Ni/Ti sequentially stacked under the first conductivity-type semiconductor layer in the through hole. The light emitting device package of claim 1 , wherein the second electrode includes a material having light reflection characteristics. The light emitting device package of claim 12 , further comprising a light-transmitting electrode layer disposed between the second electrode and the second conductivity-type semiconductor layer. According to claim 1, wherein the light emitting device package
a first pad connected to the first electrode; and
a second pad connected to the second electrode; and
The third passivation layer is disposed between the first pad and the second electrode, and is disposed between the second pad and the first electrode. The light emitting device package of claim 14 , wherein the third passivation layer comprises a dispersed Bragg reflective layer. The light emitting device package of claim 6 , wherein a width in which the 1-2 passivation layer and the 1-3 electrode overlap in a thickness direction of the light emitting structure is 2 μm or more. A light emitting device comprising the light emitting device package according to any one of claims 1 to 6 and 10 to 16.

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