KR100999725B1 - Light emitting device, method for fabricating the light emitting device and light emitting device package - Google Patents

Abstract

PURPOSE: A light emitting element, a method for manufacturing the same, and a light emitting element package are provided to improve the light emitting efficiency of the light emitting element by forming a light transmissive electrode layer on the upper region of a light emitting structure. CONSTITUTION: A light emitting structure(110) includes a first conductive semiconductor layer(112), an active layer(114), and a second conductive semiconductor layer(116). A first electrode(141) is in electric connection with the first conductive semiconductor layer. A first insulating layer(120) is formed between the lateral region of the first electrode and the light emitting structure. A second electrode(142) is in electric connection with the second conductive semiconductor layer. A light transmissive electrode layer(150) is formed on the upper region of the light emitting structure.

Description

LIGHT EMITTING DEVICE, METHOD FOR FABRICATING THE LIGHT EMITTING DEVICE AND LIGHT EMITTING DEVICE PACKAGE}

The embodiment relates to a light emitting device, a light emitting device manufacturing method and a light emitting device package.

Light emitting diodes (LEDs) may be produced by combining p-n junction diodes having characteristics of converting electrical energy into light energy by combining elements of Groups III and V of the periodic table. LED can realize various colors by adjusting the composition ratio and the material of the compound semiconductor.

When the forward voltage is applied, the n-layer electrons and the p-layer holes combine to generate light energy corresponding to the energy gap of the conduction band and the valence band.

Nitride semiconductors, which are a kind of light emitting diodes, have received great attention in the field of optical devices and high power electronic devices due to their high thermal stability and wide bandgap energy. In particular, blue LEDs, green LEDs, and ultraviolet (UV) LEDs using nitride semiconductors are commercially used and widely used.

The embodiment provides a light emitting device, a light emitting device manufacturing method and a light emitting device package having a new structure.

The embodiment provides a light emitting device having improved heat dissipation characteristics and a method of manufacturing the same.

The embodiment provides a light emitting device that is easy to install.

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

A light emitting device according to an embodiment includes a light emitting structure including a first conductive semiconductor layer, an active layer under the first conductive semiconductor layer, and a second conductive semiconductor layer under the active layer; A first electrode penetrating the active layer and the second conductive semiconductor layer and electrically connected to the first conductive semiconductor layer, and a lower region of which is exposed below the light emitting structure; A first insulating layer formed between the side region of the first electrode and the light emitting structure; A second electrode formed under the second conductive semiconductor layer and electrically connected to the second conductive semiconductor layer; And a light transmissive electrode layer formed on an upper region of the light emitting structure.

A method of manufacturing a light emitting device according to an embodiment may include forming a light emitting structure by sequentially stacking a first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer on a substrate; Selectively removing the light emitting structure to form a first cavity to expose a portion of an upper surface of the first conductivity type semiconductor layer; Forming a first insulating layer on an inner side surface of the first cavity; Forming a metal layer in the first cavity and on the light emitting structure; Selectively removing the metal layer to form electrically isolated first and second electrodes; Removing the substrate; And forming a transparent electrode layer under the first conductive semiconductor layer.

The light emitting device package according to the embodiment includes a package body; A first electrode layer and a second electrode layer provided on the package body; And a light emitting device according to any one of claims 1 to 14 installed on the package body and electrically connected to the first electrode layer and the second electrode layer.

The embodiment can provide a light emitting device having a new structure, a light emitting device manufacturing method, and a light emitting device package.

The embodiment can provide a light emitting device having improved heat dissipation characteristics and a method of manufacturing the same.

The embodiment can provide a light emitting device that is easy to install.

The embodiment can provide a light emitting device having improved light extraction efficiency.

1 is a side cross-sectional view of a light emitting device according to an embodiment
FIG. 2 is a cross-sectional view taken along the line AA ′ of FIG. 1; FIG.
3 is a rear view illustrating an electrode structure of the light emitting device of FIG. 1.
4 is a top view of a light emitting device according to another embodiment;
5 to 7 are views showing another example of the light transmissive electrode layer of the light emitting device according to the embodiment
8 is a circuit diagram illustrating a light emitting device according to an embodiment;
9 is a waveform diagram at the time of electrostatic discharge of the light emitting device according to the embodiment
10 to 19 illustrate a method of manufacturing a light emitting device according to an embodiment.
20 is a cross-sectional view of a light emitting device package including a light emitting device according to the embodiment

In the description of the embodiments, it is to be understood that each layer (film), region, pattern or structure is formed "on" or "under" a substrate, each layer The terms " on "and " under " encompass both being formed" directly "or" indirectly " In addition, the criteria for the top or bottom of each layer will be described with reference to the drawings.

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

Hereinafter, a light emitting device, a light emitting device manufacturing method, and a light emitting device package according to an embodiment will be described with reference to the accompanying drawings.

1 is a side cross-sectional view of a light emitting device 100 according to an embodiment, FIG. 2 is a cross-sectional view taken along line AA ′ of FIG. 1, and FIG. 3 is a back view showing an electrode structure of the light emitting device 100 of FIG. 1. It is also.

1 to 3, the light emitting device 100 according to the embodiment may include a first conductive semiconductor layer 112, an active layer 114 and the active layer 114 under the first conductive semiconductor layer 112. ) The light emitting structure 110 including the second conductive semiconductor layer 116 and the first conductive semiconductor layer 112 penetrating through the active layer 114 and the second conductive semiconductor layer 116. ), The first electrode 141 electrically connected to the lower region, the insulating layer 120 and 125 formed between the side region of the first electrode 141 and the light emitting structure 110, and the second conductive layer. A second electrode 142 and a light transmissive electrode layer 150 formed in an upper region of the light emitting structure 110 may be included under the type semiconductor layer 116.

In addition, a first reflective layer 130a is formed between an upper region of the first electrode 141 and the first conductive semiconductor layer 112, and the second electrode layer 142 and the second conductive semiconductor layer are formed. The second reflective layer 130b may be formed between the 116. An upper surface of the first electrode 141 is disposed inside the first conductive semiconductor layer 112.

In addition, the second reflective layer 130b may be formed to extend into the insulating layers 120 and 125 to surround side surfaces of the first electrode 141.

The light emitting device 100 according to the exemplary embodiment is formed such that lower regions of the first electrode 141 and the second electrode 142 are exposed to the outside. And, preferably, the first electrode 141 and the second electrode 142 may be formed so that the lower surface is disposed on the same plane. Accordingly, since the light emitting device 100 can be mounted on an external electrode such as a lead frame by a chip bonding method, a wire bonding process can be omitted, thereby packaging the light emitting device 100. Can improve the efficiency.

In addition, the light emitting device 100 according to the embodiment may minimize the absorption of the light generated by the light emitting structure 110 by the first and second electrodes 141 and 142. The first and second reflective layers 130a and 130b may be included around the electrode 142. Accordingly, the light incident toward the first and second electrodes 141 and 142 may be reflected by the first and second reflective layers 130a and 130b and extracted to the outside, thereby improving light extraction efficiency of the light emitting device. have.

In addition, in the light emitting device 100 according to the embodiment, the electrode structure is formed on the upper and outer surfaces of the light emitting structure 110 and the electrode structure is formed below the light emitting structure 110. It is possible to prevent the light extracted in the upper surface and the outer surface direction of the c) from being lost by being absorbed by the electrode.

In addition, the light emitting device 100 according to the exemplary embodiment has a structure in which heat generated from the light emitting structure 110 can be smoothly discharged to an external power source through the first and second electrodes 141 and 142. As illustrated in FIG. 3, the first and second electrodes 141 and 142 may be formed in most regions of the rear surface of the light emitting device 100, and the first and second electrodes 141 and 142 may be electrically connected to an external power source. Since it is connected to, the light emitting device 100 may have a good heat dissipation efficiency.

In addition, the light emitting device 100 according to the embodiment includes the light-transmitting electrode layer 150 in the upper region of the light emitting structure 110, thereby spreading a current to the light emitting structure 110, the current is the light emitting structure ( It is possible to prevent the flow flowing biased only to a portion of the region within 110. That is, the light transmitting electrode layer 150 may extend a region that substantially contributes to light emission among the areas of the light emitting structure 110, which may improve the light emitting efficiency of the light emitting device 100 according to the embodiment. .

Hereinafter, the light emitting device 100 according to the embodiment will be described in detail with reference to components.

In example embodiments, the light emitting structure 110 may be formed of a Group 3 to Group 5 compound semiconductor, for example, AlInGaN, GaAs, GaAsP, or GaP-based compound semiconductor material. Electrons and holes provided from the layers 112 and 116 may be recombined in the active layer 114 to generate light energy.

The first conductive semiconductor layer 112 may be a compound semiconductor of a Group III-V group element doped with a first conductive dopant, for example, GaN, AlN, AlGaN, InGaN, InN, InAlGaN, AlInN, AlGaAs, GaP. , GaAs, GaAsP, AlGaInP and the like. When the first conductivity type semiconductor layer 112 is an n type semiconductor layer, the first conductivity type dopant includes an n type dopant such as Si, Ge, Sn, Se, Te, or the like. The first conductivity type semiconductor layer 112 may be formed as a single layer or a multilayer, but is not limited thereto.

The active layer 114 may be formed under the first conductivity type semiconductor layer 112. In the active layer 114, electrons injected through the first conductive semiconductor layer 112 and holes injected through the second conductive semiconductor layer 116 formed thereafter meet each other and are separated by an energy band inherent to the compound semiconductor material. It is a layer that emits light with the energy to be determined.

The active layer 114 may include any one of a single quantum well structure, a multi quantum well structure (MQW), a quantum dot structure, or a quantum line structure. The active layer 114 may be formed with a period of a well layer and a barrier layer, for example, an InGaN well layer / GaN barrier layer or an InGaN well layer / AlGaN barrier layer, using a compound semiconductor material of Group III-V group elements. have.

In addition, a conductive clad layer may be formed on or under the active layer 114, and the conductive clad layer may be formed of an AlGaN-based semiconductor.

The second conductive semiconductor layer 116 may be formed under the active layer 114. The second conductive semiconductor layer 116 is a compound semiconductor of a Group III-V group element doped with a second conductive dopant, for example, GaN, AlN, AlGaN, InGaN, InN, InAlGaN, AlInN, AlGaAs, GaP, GaAs, GaAsP, AlGaInP and the like can be selected. When the second conductive semiconductor layer 116 is a p-type semiconductor layer, the second conductive dopant includes a p-type dopant such as Mg and Zn. The second conductivity type semiconductor layer 116 may be formed as a single layer or a multilayer, but is not limited thereto.

Meanwhile, the light emitting structure 110 may include an n-type semiconductor layer under the second conductive semiconductor layer 116. In addition, the first conductivity-type semiconductor layer 112 may be a p-type semiconductor layer, and the second conductivity-type semiconductor layer 116 may be implemented as an n-type semiconductor layer. Accordingly, the light emitting structure 110 may be formed of at least one of an np junction, a pn junction, an npn junction, and a pnp junction structure.

The first conductivity-type semiconductor layer 112 is electrically connected to the first electrode 141 and the second conductivity-type semiconductor layer 116, respectively, to the second electrode 142 to transfer electrons and holes from an external power source. Can be provided.

The first electrode 141 may penetrate the active layer 114 and the second conductive semiconductor layer 116, and at least an upper region thereof may be electrically connected to the first conductive semiconductor layer 112.

That is, the first electrode 141 may be formed in the first cavity 118 penetrating the active layer 114 and the second conductive semiconductor layer 116.

The lower region of the first electrode 141 may be exposed below the light emitting structure 110. For example, as illustrated in FIG. 1, the first electrode 141 may protrude to the rear surface of the light emitting structure 110, but is not limited thereto.

In addition, the first electrode 141 may have a multilayer structure.

For example, the first layer constituting the upper region of the first electrode 141 is formed of a material for forming ohmic contact to be electrically connected to the first conductivity type semiconductor layer 112, and the first electrode The third layer constituting the lower region of 141 is formed of a material having good adhesion so as to easily adhere to the external electrode, and the second layer between the first layer and the third layer may be formed of Ni, which prevents interlayer diffusion. The diffusion barrier may be formed to include at least one of a diffusion barrier metal material and a metal material such as Cu having high electrical conductivity.

That is, the first electrode 141 is formed in a single layer or a multilayer structure to include at least one of a metal material such as Cu, Ag, Al, Ni, Ti, Cr, Pd, Au, or Sn. But it is not limited thereto.

In addition, the first electrode 141 may be formed such that a side surface thereof is perpendicular or inclined with respect to the lower surface. The first cavity 118 in which the first electrode 141 is formed is formed by an etching process or a laser process including wet etching or dry etching, wherein the processes are perpendicular to or inclined with respect to the bottom surface. Cavity 118 may be formed.

4 is a view of a light emitting device 100A according to another exemplary embodiment viewed from above.

Referring to FIG. 4, a plurality of first electrodes 141 may be formed. The plurality of first electrodes 141 may be formed to smoothly spread current even in a large area of the light emitting structure 110.

The first electrode 141 may be arranged in rows and columns as illustrated, or may be disposed in various other ways, without being limited thereto.

In addition, the second reflective layer 130b and the insulating layers 120 and 125 may be formed around each of the plurality of first electrodes 141.

Referring back to FIGS. 1 to 3, the transparent electrode layer 150 may be formed in an upper region of the light emitting structure 110.

The light transmissive electrode layer 150 may spread a current on the light emitting structure 110 to prevent the current from being biased toward only a portion of the light emitting structure 110. That is, the light transmitting electrode layer 150 may extend a region that substantially contributes to light emission among the areas of the light emitting structure 110, which may improve the light emitting efficiency of the light emitting device 100 according to the embodiment. .

The light transmissive electrode layer 150 penetrates the first light transmissive electrode layer 151 formed on the upper surface of the light emitting structure 110 and the first conductive semiconductor layer 112 to pass through the first light transmissive electrode layer 151 and the first light. The second transparent electrode layer 152 may be electrically connected to the first electrode 141.

The first transmissive electrode layer 151 may be formed on the upper surface of the light emitting structure 110 to have a thickness of, for example, 100 nm to 500 nm. The first transmissive electrode layer 151 may be formed to have a relatively uniform thickness through at least one deposition method among electron beam (E-beam) deposition, sputtering, and plasma enhanced chemical vapor deposition (PECVD).

5 and 6 are diagrams illustrating another example of the first light transmitting electrode layer 151.

5 and 6, a roughness or pattern 111 may be formed on an upper surface of the first translucent electrode layer 151.

As illustrated in FIG. 5, the roughness or pattern 111 may be formed only on an upper surface of the first translucent electrode layer 151.

Alternatively, as illustrated in FIG. 6, the roughness or pattern 111 may be formed on an upper surface of the light emitting structure 110 and an upper surface of the first transmissive electrode layer 151. That is, the roughness or the pattern 111 may be formed on the upper surface of the first translucent electrode layer 151 along the roughness or the pattern formed on the upper surface of the light emitting structure 110. However, the shape of the roughness 111 or the pattern is not limited.

The roughness or pattern 111 may be randomly formed by wet etching, or may be formed to have a pattern by a patterning process. In this case, the roughness or pattern 111 may be formed to have a predetermined period, which may be determined according to the wavelength of light emitted from the light emitting structure 110. The roughness or pattern 111 may be, for example, a photonic crystal structure having a period of 200 nm to 3000 nm.

Referring back to FIGS. 1 to 3, the second translucent electrode layer 152 may electrically connect the first translucent electrode layer 151 and the first electrode 141.

The second transmissive electrode layer 152 may be formed by forming a second cavity in the first conductive semiconductor layer 112 by an etching process or a laser drilling process and filling a conductive material in the second cavity.

As illustrated in FIG. 1, the side surface of the second light transmissive electrode layer 152 is formed perpendicular to the first light transmissive electrode layer 151.

However, as shown in FIG. 7, the side surface of the second translucent electrode layer 152 may be formed to be inclined with respect to the first translucent electrode layer 151 according to the etching process or the laser drilling process. For example, a side surface of the light transmissive electrode layer 152 may have an inclination θ of 30 ° to 80 ° with respect to the first light transmissive electrode layer 151.

In addition, the second transmissive electrode layer 152 is not only formed on the first reflective layer 130a but may be further formed on the insulating layers 120 and 125. That is, the diameter of the second light transmissive electrode layer 152 is not limited.

The transmissive electrode layer 150 is preferably formed of a material having light transmissivity and electrical conductivity, and specifically, indium tin oxide (ITO), indium zinc oxide (IZO), indium zinc tin oxide (IZTO), and indium aluminum zinc oxide), indium gallium zinc oxide (IGZO), indium gallium tin oxide (IGTO), aluminum zinc oxide (AZO), antimony tin oxide (ATO), gallium zinc oxide (GZO), IrOx, RuOx, Ni, Ag, or Au It may be formed to have a single layer or a multi-layer structure, including one or more of.

1 to 3, the second electrode 142 may be formed under the second conductive semiconductor layer 116. The second electrode 142 may be electrically connected to the second conductive semiconductor layer 116, and may provide power to the light emitting structure 110 together with the first electrode 141.

The second electrode 142 may be formed to be spaced apart from the first electrode 141 by a predetermined interval to prevent electrical short. For example, the interval may be 10 μm to 50 μm, but is not limited thereto.

In addition, a bottom surface of the second electrode 142 may be formed on the same plane as a bottom surface of the first electrode 141. Accordingly, the light emitting device 100 may be mounted on an external electrode such as a lead frame by a chip bonding method.

The chip bonding method is a method in which the first electrode 141 and the second electrode 142 and an external electrode are opposed to each other and electrically connected to each other by bonding them with a soldering material or a bonding metal, so that a wire bonding process is unnecessary. The yield and efficiency of the process of packaging the light emitting device 100 may be improved.

In addition, the second electrode 142 may have a multilayer structure. For example, a first layer constituting the upper region of the second electrode 142 is formed of a material forming ohmic contact to be electrically connected to the second conductivity type semiconductor layer 116, and the second electrode The third layer constituting the lower region of 142 is formed of a material having good adhesion so as to easily adhere to the external electrode, and the second layer between the first layer and the third layer is formed of Ni, which prevents interlayer diffusion. The diffusion barrier may be formed to include at least one of a diffusion barrier metal material and a metal material such as Cu having high electrical conductivity.

That is, the second electrode 142 is formed in a single layer or a multilayer structure to include at least one of a metal material such as Cu, Ag, Al, Ni, Ti, Cr, Pd, Au, or Sn. But it is not limited thereto.

Meanwhile, as shown in FIG. 3, the first electrode 141 and the second electrode 142 may be formed in most regions of the rear surface of the light emitting device 100 according to the embodiment. That is, the first and second electrodes 141 and 142 may be formed on the rear surface of the light emitting device 100 except for a predetermined interval to prevent electrical short between the electrodes. However, the structure of the first and second electrodes 141 and 142 is not limited.

Therefore, the electrode structure is formed on the upper surface and the outer surface of the light emitting device 100 according to the embodiment, and the electrode structure is formed on the rear surface of the light emitting device 100, the upper surface and the outer surface direction of the light emitting device 100 It is possible to prevent the light to be extracted by being absorbed by the electrode structure to be lost.

In addition, since the first and second electrodes 141 and 142 occupy most of the area of the rear surface of the light emitting device 100 according to the embodiment, the heat generated in the light emitting structure 110 is the first and second electrodes 141 and 142. ) Can be effectively transmitted to the external power source to be discharged.

In addition, the first electrode 141 and the second electrode 142 may serve to support the light emitting structure 110.

The reflective layer 130 including the first and second reflective layers 130a and 130b may be formed around the first electrode 141 and the second electrode 142. The reflective layer 130 may minimize light absorbed by the first and second electrodes 141 and 142 by reflecting light incident from the light emitting structure 110.

The first reflective layer 130a may be formed between at least an upper region of the first electrode 141 and the first conductive semiconductor layer 112.

In addition, when the first conductive semiconductor layer 112 and the first electrode 141 do not form ohmic contact, the material of the first reflective layer 130a is the first conductive semiconductor layer 112. It may be selected as a material to form an ohmic contact with.

The second reflective layer 130b may be formed between the second conductive semiconductor layer 116 and the light emitting structure 110. In addition, the second reflective layer 130b may be further formed to surround the side region of the first electrode 141. That is, the second reflective layer 130b is formed in the side region of the first electrode 141 and the upper region of the second electrode 142 to reflect the light incident from the active layer 114 to emit the light emitting device. It can contribute to the light extraction efficiency improvement of (100).

In addition, when the second conductive semiconductor layer 116 and the second electrode 142 do not form ohmic contact, the material of the second reflective layer 130b is the second conductive semiconductor layer 116. It may be selected as a material to form an ohmic contact with.

The first reflective layer 130a and the second reflective layer 130b may include, for example, at least one of Ag, Ni, Al, Rh, Pd, Ir, Ru, Mg, Zn, Pt, Au, and Hf. Or an alloy. In addition, the first and second reflective layers 130a and 130b may be formed in multiple layers using the metal or alloy and a light-transmitting conductive material such as IZO, IZTO, IAZO, IGZO, IGTO, AZO, or ATO. It may be formed of IZO / Ni, AZO / Ag, IZO / Ag / Ni, AZO / Ag / Ni and the like.

The first reflective layer 130a and the second reflective layer 130b may be formed of the same or different materials, but the embodiment is not limited thereto.

Meanwhile, the first electrode 141 is formed to penetrate the active layer 114 and the second conductive semiconductor layer 116, and an upper region is electrically connected to the first conductive semiconductor layer 112. In addition, the insulating layers 120 and 125 may be formed on side surfaces of the first electrode 141 to prevent electrical shorts in the light emitting structure 110. That is, the insulating layers 120 and 125 may be formed between at least the side region of the first electrode 141 and the light emitting structure 110.

However, when the second reflective layer 130b is formed between the side region of the first electrode 141 and the light emitting structure 110, the insulating layers 120 and 125 are formed of the first electrode 141 and the second electrode. The electrical short between the reflective layer 130b and the electrical short between the second reflective layer 130b and the light emitting structure 110 may be prevented.

In this case, the insulating layers 120 and 125 may include a first insulating layer 120 formed between the second reflective layer 130b and the light emitting structure 110, a side region of the first electrode 141, and the second insulating layer 120. The second insulating layer 125 may be formed between the reflective layers 130b. In addition, the second insulating layer 125 is disposed between the first electrode 141 and the second electrode 142. That is, since the second reflective layer 130b extends into the insulating layers 120 and 125, the electrical short may be prevented while maintaining the reflection effect of the second reflective layer 130b.

Meanwhile, as shown in FIG. 1, upper regions of the first insulating layer 120 and the second insulating layer 125 may contact each other. In addition, the second insulating layer 125 may be formed to expose a portion between the first electrode 141 and the second electrode 142. Accordingly, the first electrode 141 and the second electrode are exposed. The interval between the 142 may be maintained and the reliability of the light emitting device 100 may be improved. For example, the interval may be 10 μm to 50 μm, but is not limited thereto.

The insulating layers 120 and 125 may be formed of a material having transparency and electrical insulation. For example, the insulating layers 120 and 125 may be SiO ₂ , SiO _x , SiO _x N _y , It may be formed of at least one of Si ₃ N ₄ , Al ₂ O ₃ or TiO _x but is not limited thereto.

In addition, the first insulating layer 120 and the second insulating layer 125 may be formed of the same or different materials.

Meanwhile, the insulating layers 120 and 125 serve as a dielectric formed between the light emitting structure 110 and the first electrode 141 formed of a conductive material, thereby generating a capacitor component C _D (see FIG. 1). Can be.

The capacitor component C _D has a withstand voltage effect of protecting the light emitting structure 110 when an abrupt reverse voltage is applied to the light emitting device 100 according to the embodiment to generate an electrostatic discharge (ESD). . This will be described below in detail.

8 is a circuit diagram illustrating a light emitting device 100 according to an embodiment.

Referring to FIG. 8, the capacitor component C _D may be connected to the light emitting structure 110 in parallel. Since the capacitor component C _D appears between the light emitting structure 110 and the second reflective layer 130b and between the second reflective layer 130b and the first electrode 141, the light emitting structure 110 may be used. And in parallel.

When forward voltage is applied to the light emitting device 100, current flows through the light emitting structure 110 to emit light. However, when a reverse voltage is applied according to the electrostatic discharge, at least a portion of the current may flow through the capacitor component C _D.

That is, since at least a part of the excess current flows through the capacitor component C _D during electrostatic discharge, the amount of current flowing through the active layer 114 is reduced, resulting in damage to the active layer 114 by breakdown. It can be minimized.

At this time, when the voltage is reversed according to the electrostatic discharge, the larger the total capacitance (C _Tot ), the smaller the current flowing to the active layer due to the ESD stress, thereby alleviating the shock caused by the electrostatic discharge. This is explained by the formula below.

Q _Dis = C _ESD V _ESD (Q _Dis is the amount of charge at discharging, C _ESD is the capacitance at discharging)

C _Tot = C _D

I = dQ / dt = △ Q / τ = Q _Dis / (RC _Tot ) ∴ C _Tot ↑-> I ↓

That is, when the voltage is reverse according to the electrostatic discharge, the total capacitance (C _Tot ), that is, the larger the capacitor component (C _D ) between the first electrode 141 and the light emitting structure 110, flows to the active layer due to ESD stress. The current I can be made small to alleviate the impact.

Therefore, in order to increase the capacitor component C _D , the material forming the insulating layers 120 and 125 may be formed of an insulating material having a high dielectric constant?, For example, TiO ₂ . However, this is not limitative.

9 is a waveform diagram at the time of electrostatic discharge of the light emitting device 100 according to the embodiment.

Referring to FIG. 9, as shown in the following equation, a pulse waveform has a high frequency component when the Fourier transform is performed, and as the rising time (t _r ) of the pulse waveform is steep, the magnitude of the high frequency component increases.

Impedance: Z = Z _R + jZ _Im (Z _R is Real Impedance, j is imaginary factor, Z _Im is impedance due to capacitor)

Capacitor: Z _{Im, C} = 1 / (jωC _D ), (ω = 2πf)

Substituting this into the light emitting device 100 according to the embodiment, as the reverse voltage caused by electrostatic discharge is rapidly applied to the light emitting device 100, the capacitor component C _D becomes larger, and thus the light emitting device 100 Withstand voltage characteristics can be improved. That is, according to the exemplary embodiment, the light emitting device 100 having improved withstand voltage characteristics with respect to a sudden excessive current may be provided.

Hereinafter, a method of manufacturing a light emitting device according to an embodiment will be described in detail. However, the description overlapping with the above description will be omitted or briefly described.

10 to 19 illustrate a method of manufacturing the light emitting device 100 according to the embodiment.

Referring to FIG. 10, the light emitting structure 110 may be formed on a substrate 101.

The substrate 101 may use at least one of sapphire (Al ₂ O ₃ ), SiC, GaN, Si, ZnO, AlN, GaAs, β-Ga ₂ O ₃ , GaP, InP, and Ge.

The light emitting structure 110 may be formed by sequentially stacking the first conductive semiconductor layer 112, the active layer 114, and the second conductive semiconductor layer 116 on the substrate 101. .

The light emitting structure 110 may include, for example, a metal organic chemical vapor deposition (MOCVD), a chemical vapor deposition (CVD), a plasma chemical vapor deposition (PECVD), a molecular beam. Molecular Beam Epitaxy (MBE), Hydride Vapor Phase Epitaxy (HVPE), etc. may be formed using, but is not limited thereto.

On the other hand, between the substrate 101 and the first conductivity-type semiconductor layer 112, to reduce the lattice constant and thermal expansion coefficient difference between the two layers, to improve the crystallinity of the light emitting structure 110 ( Not shown) and an undoped semiconductor layer (not shown) may be further formed.

Referring to FIG. 11, the light emitting structure 110 may be selectively removed to form a first cavity 118 to expose a portion of an upper surface of the first conductive semiconductor layer 112.

The first cavity 118 may be formed by an etching process including wet etching and dry etching, or may be formed by a laser process, but is not limited thereto. In addition, the inner surface of the first cavity 118 may be formed to be perpendicular to or inclined with respect to the bottom surface by the etching process or the laser process.

The first cavity 118 may be formed to pass through the second conductive semiconductor layer 116 and the active layer 114 to expose the first conductive semiconductor layer 112.

Referring to FIG. 12, the first insulating layer 120 may be formed on an inner side surface of the first cavity 118.

The first insulating layer 120 may be formed by a deposition process such as electron beam (E-beam) deposition, sputtering, and plasma enhanced chemical vapor deposition (PECVD), but is not limited thereto.

Meanwhile, the deposition process may be performed after forming a mask (not shown) in the first cavity 118. The shape of the first insulating layer 120 may also vary according to the shape of the mask (not shown). have.

As illustrated, for example, the first insulating layer 120 may include an inner side surface of the first cavity 118, a partial region of the bottom surface of the first cavity 118, and the second conductivity type semiconductor. It may be formed in a portion of the upper surface of the layer 116.

Referring to FIG. 13, the first reflective layer 130a is formed on the bottom surface of the first cavity 118, and the second reflective layer 130b is formed on the second conductive semiconductor layer 116. Can be.

In addition, the second reflective layer 130b may be further formed inside the first insulating layer 120 formed in the first cavity 118.

The first and second reflective layers 130a and 130b may be formed by a deposition process such as electron beam (E-beam) deposition, sputtering, and plasma enhanced chemical vapor deposition (PECVD), or may be formed by a plating process. It does not limit to this.

Referring to FIG. 14, the second insulating layer 125 may be formed to surround the inside of the second reflective layer 130b formed in the first cavity 118. In addition, the second insulating layer 125 may be further formed on an upper surface of the second reflective layer 130b.

That is, the second insulating layer 125 may be formed except for a portion of the upper surface of the second reflective layer 130b on which the second electrode 142 is formed in a subsequent process, and thus the second reflective layer 130b. Can prevent electrical short.

The second insulating layer 125 may be formed by a deposition process such as electron beam (E-beam) deposition, sputtering, plasma enhanced chemical vapor deposition (PECVD), and the like, and the first insulating layer 120 It may be formed by the same method.

Referring to FIG. 15, a metal layer 140 may be formed on an upper surface of the light emitting device of FIG. 10. That is, the metal layer 140 may be formed in the first cavity 118 and on the upper surface of the second reflective layer 130b.

The metal layer 140 may be formed by a plating process including at least one of electrolytic plating and electroless plating, or may be formed by a deposition process, but is not limited thereto.

Referring to FIG. 16, the first electrode 141 and the second electrode 142 may be formed by selectively removing the metal layer 140.

For example, the first and second electrodes 141 and 142 may be formed by forming a mask (not shown) on the metal layer 140 and then performing an etching process along the mask (not shown). However, this is not limitative.

16 and 17, the substrate 101 may be removed under the light emitting structure 110.

The substrate 101 may be removed by at least one of a laser lift off (LLO) process, a chemical lift off (CLO), or a physical polishing method, but is not limited thereto.

In addition, the substrate 101 is preferably removed after the metal layer 140 is formed for reliability of the manufacturing process, but the order of the manufacturing process is not limited.

In addition, after the substrate 101 is removed, an etching process may be performed on the exposed surface of the light emitting structure 110 to remove residues and to form roughness or a pattern for improving light extraction.

Referring to FIG. 18, the first electrode 141 or the first reflective layer is formed by selectively removing the first conductivity-type semiconductor layer 112 of the light emitting structure 110 to form a second cavity 155. An upper surface of the 130a may be exposed.

The second cavity 155 may be formed, for example, in at least one of an etching process and a laser drilling process, but is not limited thereto.

In addition, the inner surface of the second cavity 155 may be formed to be vertical or inclined according to the etching process or the laser drilling process.

Referring to FIG. 19, the light emitting device 100 according to the exemplary embodiment may be provided by forming the transparent electrode layer 150 on the second cavity 155 and the light emitting structure 110.

The light transmissive electrode layer 150 penetrates the first light transmissive electrode layer 151 formed on the upper surface of the light emitting structure 110 and the first conductive semiconductor layer 112 to pass through the first light transmissive electrode layer 151 and the first light. The second transparent electrode layer 152 may be electrically connected to the first electrode 141.

The transparent electrode layer 150 may be formed by at least one deposition method of electron beam (E-beam) deposition, sputtering, plasma enhanced chemical vapor deposition (PECVD), or may be formed by a plating method, and is limited thereto. I do not.

Meanwhile, in the method of manufacturing a light emitting device according to the embodiment, the first electrode 141 is described as being formed before the light transmissive electrode layer 150, but the light transmissive electrode layer 150 is first formed and then the first electrode ( 141 may be formed.

<Light Emitting Device Package>

20 is a cross-sectional view of a light emitting device package including the light emitting device 100 according to the embodiment.

Referring to FIG. 20, the light emitting device package according to the embodiment may include a package body 20, a first electrode layer 31 and a second electrode layer 32 installed on the package body 20, and the package body 20. The light emitting device 100 according to the embodiment, which is installed at and electrically connected to the first electrode layer 31 and the second electrode layer 32, and a molding member 40 surrounding the light emitting device 100. .

The package body 20 may include a silicon material, a synthetic resin material, or a metal material, and an inclined surface may be formed around the light emitting device 100.

The first electrode layer 31 and the second electrode layer 32 are electrically separated from each other, and provide power to the light emitting device 100. In addition, the first electrode layer 31 and the second electrode layer 32 may increase light efficiency by reflecting the light generated from the light emitting device 100, and externally generate heat generated from the light emitting device 100. May also act as a drain.

Any one of the first and second electrode layers 31 and 32 may be formed through the package body 20, which may be modified according to the electrode structure of the light emitting device 100.

The light emitting device 100 may be installed on the package body 20 or on the first electrode layer 31 or the second electrode layer 32.

The light emitting device 100 may be electrically connected to the first electrode layer 31 and the second electrode layer 32 by any one of a wire method, a flip chip method, or a die bonding method.

The molding member 40 may surround and protect the light emitting device 100. In addition, the molding member 40 may include a phosphor to change the wavelength of the light emitted from the light emitting device 100.

The light emitting device package may mount at least one of the light emitting devices of the above-described embodiments as one or more, but is not limited thereto.

In addition, the light emitting device package includes a chip on board (COB) type, the top surface of the package body 20 is flat, a plurality of light emitting devices 100 may be installed on the package body 20.

A plurality of light emitting device packages according to the embodiment may be arranged on a substrate, and a light guide plate, a prism sheet, a diffusion sheet, or the like, which is an optical member, may be disposed on an optical path of the light emitting device package. The light emitting device package, the substrate, and the optical member may function as a light unit. Another embodiment may be implemented as a display device, an indicator device, or a lighting system including the semiconductor light emitting device or the light emitting device package described in the above embodiments, for example, the lighting system may include a lamp and a street lamp. .

Features, structures, effects, and the like described in the above embodiments are included in at least one embodiment of the present invention, and are not necessarily limited to only one embodiment. Furthermore, the features, structures, effects, and the like illustrated in the embodiments may be combined or modified with respect to other embodiments by those skilled in the art to which the embodiments belong. Therefore, it should be understood that the present invention is not limited to these combinations and modifications.

In addition, the above description has been made with reference to the embodiment, which is merely an example, and is not intended to limit the present invention. Those skilled in the art to which the present invention pertains will be illustrated as above without departing 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 can be modified. And differences relating to such modifications and applications will have to be construed as being included in the scope of the invention defined in the appended claims.

100: light emitting device 110: light emitting structure
112: first conductive semiconductor layer 114: active layer
116: second conductive semiconductor layer 120: first insulating layer
125: second insulating layer 130a: first reflective layer
130b: second reflective layer 141: first electrode
142: second electrode 150: translucent electrode layer

Claims (20)

A light emitting structure comprising a first conductive semiconductor layer, an active layer under the first conductive semiconductor layer, and a second conductive semiconductor layer under the active layer;
A first electrode penetrating the active layer and the second conductive semiconductor layer and electrically connected to the first conductive semiconductor layer, and a lower region of which is exposed below the light emitting structure;
A first insulating layer formed between the side region of the first electrode and the light emitting structure;
A second electrode formed under the second conductive semiconductor layer and electrically connected to the second conductive semiconductor layer; And
A light emitting device comprising a transmissive electrode layer formed on an upper region of the light emitting structure. The method of claim 1,
The light transmissive electrode layer includes a first light transmissive electrode layer formed on an upper surface of the light emitting structure, and a second light transmissive electrode layer penetrating the first conductive semiconductor layer to electrically connect the first light transmissive electrode layer and the first electrode. device. The method of claim 1,
The light transmissive electrode layer includes a light emitting device including a material having transparency and electrical conductivity. The method of claim 3,
The light transmissive electrode layer may be formed of indium tin oxide (ITO), indium zinc oxide (IZO), indium zinc tin oxide (IZTO), indium aluminum zinc oxide (IAZO), indium gallium zinc oxide (IGZO), indium gallium tin oxide (IGTO), A light emitting device comprising at least one of aluminum zinc oxide (AZO), antimony tin oxide (ATO), gallium zinc oxide (GZO), IrOx, RuOx, Ni, Ag, or Au. The method of claim 2,
And the second light transmitting electrode layer is perpendicular to the first light transmitting electrode layer. The method of claim 2,
A side surface of the second light-transmitting electrode layer has a slope with respect to the first light-transmissive electrode layer. The method of claim 2,
The light emitting device has a thickness of the light transmitting electrode layer is 100nm to 500nm. The method of claim 1,
A light emitting device having a roughness or a pattern formed on an upper surface of the light transmissive electrode layer. The method of claim 1,
A light emitting device in which a lower surface of the first electrode and the second electrode are disposed on the same plane. The method of claim 1,
And a second insulating layer disposed between the lower surface of the first electrode and the lower surface of the second electrode to electrically isolate the first electrode and the second electrode. The method of claim 1,
A light emitting device comprising a first reflective layer between the first electrode and the first conductive semiconductor layer. The method of claim 1,
A light emitting device comprising a second reflective layer between the second electrode and the second conductive semiconductor layer. The method of claim 12,
The second reflective layer is formed to extend into the insulating layer to surround the side region of the first electrode. The method of claim 1,
The first electrode extends so that the top surface of the first electrode is positioned inside the first conductive semiconductor layer. Sequentially stacking a first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer on a substrate to form a light emitting structure;
Selectively removing the light emitting structure to form a first cavity to expose a portion of an upper surface of the first conductivity type semiconductor layer;
Forming a first insulating layer on an inner side surface of the first cavity;
Forming a metal layer in the first cavity and on the light emitting structure;
Selectively removing the metal layer to form electrically isolated first and second electrodes;
Removing the substrate; And
A light emitting device manufacturing method comprising the step of forming a transparent electrode layer under the first conductive semiconductor layer. 16. The method of claim 15,
Forming the light transmitting electrode layer,
Forming a second cavity penetrating the first conductive semiconductor layer and in contact with a bottom surface of the first electrode; And
And forming a translucent electrode layer under the second cavity and the light emitting structure. 17. The method of claim 16,
The second cavity is a light emitting device manufacturing method formed by an etching process or a laser drilling process. 16. The method of claim 15,
After the forming of the first insulating layer,
And forming a first reflective layer on the bottom surface of the first cavity. 16. The method of claim 15,
After the forming of the first insulating layer,
Forming a second reflective layer on an upper surface of the second conductive semiconductor layer and inside the first insulating layer; And
And forming a second insulating layer inside the second reflective layer formed in the first cavity. Package body;
A first electrode layer and a second electrode layer provided on the package body; And
The light emitting device package of claim 1, wherein the light emitting device is installed on the package body, and includes the light emitting device of claim 1 electrically connected to the first electrode layer and the second electrode layer.

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