KR102639844B1 - Light emitting device - Google Patents

Abstract

The embodiment includes a plurality of light emitting units spaced apart from each other on a first conductivity type semiconductor layer; a first electrode electrically connected to the first conductive semiconductor layer; a plurality of second electrodes electrically connected to the plurality of light emitting units; an insulating layer disposed on the first electrode and the plurality of second electrodes; It includes a first pad and a second pad disposed on the insulating layer, the plurality of light emitting units each include an active layer and a second conductivity type semiconductor layer, and the first electrode is at least one of the plurality of light emitting units. is disposed surrounding the light-emitting portion, the second pad penetrates the insulating layer and is electrically connected to the plurality of second electrodes, and the first pad initiates a light-emitting device that is electrically connected to the first electrode.

Description

Light emitting device {LIGHT EMITTING DEVICE}

The embodiment relates to a light emitting device.

Semiconductor devices containing compounds such as GaN and AlGaN have many advantages, such as having a wide and easily adjustable band gap energy, and can be used in a variety of ways, such as light emitting devices, light receiving devices, and various diodes.

In particular, light-emitting devices such as light emitting diodes and laser diodes using group 3-5 or group 2-6 compound semiconductor materials have been developed into red, green, and green colors through the development of thin film growth technology and device materials. Various colors such as blue and ultraviolet rays can be realized, and efficient white light can also be realized by using fluorescent materials or combining colors. Compared to existing light sources such as fluorescent lights and incandescent lights, it has low power consumption, semi-permanent lifespan, and fast response speed. , has the advantages of safety and environmental friendliness.

In addition, when light-receiving devices such as photodetectors or solar cells are manufactured using group 3-5 or group 2-6 compound semiconductor materials, the development of device materials absorbs light in various wavelength ranges to generate photocurrent. By doing so, light of various wavelengths, from gamma rays to radio wavelengths, can be used. In addition, it has the advantages of fast response speed, safety, environmental friendliness, and easy control of device materials, so it can be easily used in power control, ultra-high frequency circuits, or communication modules.

Therefore, semiconductor devices can replace the transmission module of optical communication means, the light emitting diode backlight that replaces the cold cathode fluorescence lamp (CCFL) that constitutes the backlight of LCD (Liquid Crystal Display) display devices, and fluorescent or incandescent light bulbs. Applications are expanding to include white light-emitting diode lighting devices, automobile headlights and traffic lights, and sensors that detect gas or fire. Additionally, the applications of semiconductor devices can be expanded to high-frequency application circuits, other power control devices, and communication modules.

In particular, light-emitting devices that emit light in the ultraviolet wavelength range have a curing or sterilizing effect and can be used for curing, medical purposes, and sterilization.

Recently, research on ultraviolet light-emitting devices has been active, but it is still difficult to implement ultraviolet light-emitting devices with flip chips.

The embodiment provides a flip chip type ultraviolet light emitting device.

Additionally, a light emitting device with improved luminous efficiency is provided.

The problem to be solved in the embodiment is not limited to this, and it will also include means of solving the problem described below and purposes and effects that can be understood from the embodiment.

A light emitting device according to an aspect of the present invention includes a plurality of light emitting units spaced apart from each other on a first conductivity type semiconductor layer; a first electrode electrically connected to the first conductive semiconductor layer; a plurality of second electrodes electrically connected to the plurality of light emitting units; an insulating layer disposed on the first electrode and the plurality of second electrodes; It includes a first pad and a second pad disposed on the insulating layer, the plurality of light emitting units each include an active layer and a second conductivity type semiconductor layer, and the first electrode is at least one of the plurality of light emitting units. is disposed surrounding the light emitting portion, the second pad penetrates the insulating layer and is electrically connected to the plurality of second electrodes, and the first pad is electrically connected to the first electrode.

The plurality of light emitting units include at least one first light emitting unit vertically overlapping with the first pad and a plurality of second light emitting units vertically overlapping with the second pad, and the first electrode includes the at least one light emitting unit. and an extension part extending onto the first light emitting part, and the first pad may penetrate the insulating layer and be electrically connected to the extension part.

The area of the first light emitting unit may be larger than the area of the plurality of second light emitting units.

The area of the first pad may be 10% to 30% of the area of the second pad.

The plurality of light emitting units may have a circular shape or a polygonal shape.

The plurality of light emitting units may have a circular shape, and the diameter of the plurality of light emitting units may be 30 μm to 70 μm.

The aluminum composition of the first conductive semiconductor layer, the active layer, and the second conductive semiconductor layer may be 40% or more.

The sizes of the plurality of light emitting units may be different from each other.

The total area of the active layer disposed in the plurality of light emitting units may be 50% to 90% of the maximum area of the light emitting device.

The aluminum composition of the first conductive semiconductor layer, the active layer, and the second conductive semiconductor layer may be 40% or more, and the diameter of the plurality of light emitting parts may be 30 μm to 70 μm.

The active layer may emit light having a main peak between 100 nm and 310 nm.

It may include a barrier rib disposed between the first pad and the second pad, and the insulating layer may be disposed on the barrier rib.

The height ratio of the upper surface of the first pad and the insulating layer disposed on the partition may be 1:0.8 to 1:1.

The partition wall can prevent short circuit between the first pad and the second pad.

A light emitting device according to another feature of the present invention includes a plurality of light emitting units spaced apart on a first conductivity type semiconductor layer, and the plurality of light emitting units each include an active layer and a second conductivity type semiconductor layer disposed on the active layer. A light emitting structure comprising; a first electrode disposed on the first conductive semiconductor layer; a plurality of second electrodes disposed on the plurality of light emitting units; a first insulating layer disposed on the first electrode and the plurality of second electrodes; a second insulating layer disposed on the first insulating layer; a channel electrode disposed between the first insulating layer and the second insulating layer; a first pad electrically connected to the first electrode; and a second pad electrically connected to the second electrode, wherein the plurality of light emitting units include a first light emitting unit that overlaps the first pad in a vertical direction and a second light emitting unit that overlaps the second pad in the vertical direction. The channel electrode may electrically connect the first light emitting unit and the second light emitting unit, and the second insulating layer may be disposed between the channel electrode and the first pad.

The area of the first pad may be 10% to 30% of the area of the second pad.

The area of the second pad may be the same as the first pad.

According to the embodiment, a flip chip type ultraviolet light emitting device can be manufactured.

Additionally, luminous efficiency can be improved.

The various and beneficial advantages and effects of the present invention are not limited to the above-described content, and may be more easily understood through description of specific embodiments of the present invention.

1 is a plan view of a light emitting device according to a first embodiment of the present invention;
Figure 2 is a cross-sectional view taken along the AA direction of Figure 1;
3A is a plan view showing the first electrode and the second electrode;
Figure 3b is a modified example of Figure 2,
Figure 4a is a first modified example of Figure 1;
Figure 4b is a second modification of Figure 2,
Figure 5 is a cross-sectional view of a light emitting device according to a second embodiment of the present invention;
Figure 6 is a cross-sectional view in the BB direction of Figure 5,
Figure 7 is a plan view of a light emitting device according to a third embodiment of the present invention;
Figure 8 is a cross-sectional view in the CC direction of Figure 7,
Figure 9 is a plan view of a light emitting device according to a fourth embodiment of the present invention;
Figure 10 is a cross-sectional view in the DD direction of Figure 9;
Figure 11 is a cross-sectional view in the EE direction of Figure 9;
12 is a top view of the first electrode and the active layer;
Figure 13 is a plan view of a light emitting device according to a fifth embodiment of the present invention;
Figure 14 is a cross-sectional view in the FF direction of Figure 13,
15 is a top view of the first electrode and the active layer;
Figure 16 is a cross-sectional view of Figure 13 seen from another direction;
Figure 17 is a plan view of a light emitting device according to a sixth embodiment of the present invention;
Figure 18 is a plan view of a light emitting device according to a seventh embodiment of the present invention;
Figure 19 is a cross-sectional view of a light emitting device package according to an embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings.

However, the technical idea of the present invention is not limited to some of the described embodiments, but may be implemented in various different forms, and as long as it is within the scope of the technical idea of the present invention, one or more of the components may be optionally used between the embodiments. It can be used by combining and replacing.

In addition, terms (including technical and scientific terms) used in the embodiments of the present invention, unless specifically defined and described, are generally understood by those skilled in the art to which the present invention pertains. It can be interpreted as meaning, and the meaning of commonly used terms, such as terms defined in a dictionary, can be interpreted by considering the contextual meaning of the related technology.

Additionally, the terms used in the embodiments of the present invention are for describing the embodiments and are not intended to limit the present invention.

In this specification, the singular may also include the plural unless specifically stated in the phrase, and when described as "at least one (or more than one) of A and B and C", it is combined with A, B, and C. It can contain one or more of all possible combinations.

Additionally, when describing the components of an embodiment of the present invention, terms such as first, second, A, B, (a), and (b) may be used.

These terms are only used to distinguish the component from other components, and are not limited to the essence, sequence, or order of the component.

And, when a component is described as being 'connected', 'coupled' or 'connected' to another component, the component is not only directly connected, coupled or connected to that other component, but also is connected to that component. It can also include cases where other components are 'connected', 'combined', or 'connected' due to another component between them.

Additionally, when described as being formed or disposed "above" or "below" each component, "above" or "below" refers not only to cases in which two components are in direct contact with each other; It also includes cases where one or more other components are formed or disposed between two components. In addition, when expressed as "top (above) or bottom (bottom)", it may include not only the upward direction but also the downward direction based on one component.

FIG. 1 is a plan view of a light emitting device according to a first embodiment of the present invention, FIG. 2 is a cross-sectional view in the direction A-A of FIG. 1, FIG. 3A is a plan view showing a first electrode and a second electrode, and FIG. 3B is a plan view of a light emitting device according to a first embodiment of the present invention. This is a modified example.

Referring to Figures 1 and 2, the light emitting device according to the embodiment includes a plurality of light emitting parts 120a and 120b spaced apart on the first conductive semiconductor layer 124, and a plurality of light emitting parts 120a , 120b) is a light emitting structure 120 including an active layer 126 and a second conductive semiconductor layer 127, a first electrode 142 disposed on the first conductive semiconductor layer 124, and a plurality of A plurality of second electrodes 146 disposed on the light emitting units 120a and 120b, an insulating layer 160 disposed on the first electrode 142 and the plurality of second electrodes 146, and a first pad ( 171) and a second pad 172.

The light emitting structure 120 according to an embodiment of the present invention can output light in the ultraviolet wavelength range. For example, the light emitting structure 120 may output light in the near-ultraviolet wavelength range (UV-A), light in the far-ultraviolet wavelength range (UV-B), or light in the deep ultraviolet wavelength range (UV- C) can be output.

For example, light in the near-ultraviolet wavelength range (UV-A) may have a main peak in the range of 320 nm to 390 nm, and light in the far-ultraviolet wavelength range (UV-B) may have a main peak in the range of 280 nm to 320 nm, Light in the deep ultraviolet wavelength range (UV-C) may have a main peak in the range of 100 nm to 280 nm. The main peak may be the point with the highest intensity in the entire luminescent area.

When the light emitting structure 120 emits light in the ultraviolet wavelength range, each semiconductor layer of the light emitting structure 120 may include Al _x1 Ga _{1 - x1} N (0<x1≤1) material containing aluminum. Here, the composition of Al can be expressed as the ratio of the total atomic weight including Ga atomic weight and Al atomic weight and Al atomic weight. For example, if the Al composition is 40%, the Ga composition may be 60% Al ₄₀ Ga ₆₀ N.

The substrate 110 may be formed of a material selected from sapphire (Al ₂ O ₃ ), SiC, GaAs, GaN, ZnO, Si, GaP, InP, and Ge, but is not limited thereto. The substrate 110 may be a light transmitting substrate capable of transmitting light in the ultraviolet wavelength range. At this time, the top edge 110a of the substrate 110 may be exposed to the outside of the light emitting structure 120 through an etching process. Accordingly, the substrate 110 may be wider than the light emitting structure 120 to improve optical characteristics and/or reliability.

A buffer layer (not shown) may alleviate lattice mismatch between the substrate 110 and the semiconductor layers. The buffer layer may be a combination of group III and group V elements or may include any one of AlN, AlGaN, InAlGaN, and AlInN. In this embodiment, the buffer layer may be AlN, but is not limited thereto. The buffer layer may include, but is not limited to, a dopant.

The first conductive semiconductor layer 124 may be implemented as a compound semiconductor such as group III-V or group II-VI, and may be doped with a first dopant. _{The first} conductive semiconductor _layer 124 is a semiconductor material with a composition formula of _In For example, it may be selected from AlGaN, AlN, InAlGaN, etc. And, the first dopant may be an n-type dopant such as Si, Ge, Sn, Se, or Te. When the first dopant is an n-type dopant, the first conductive semiconductor layer 124 doped with the first dopant may be an n-type semiconductor layer.

The active layer 126 may be disposed between the first conductive semiconductor layer 124 and the second conductive semiconductor layer 127. The active layer 126 is a layer where electrons (or holes) injected through the first conductive semiconductor layer 124 and holes (or electrons) injected through the second conductive semiconductor layer 127 meet. The active layer 126 transitions to a low energy level as electrons and holes recombine, and can generate light having an ultraviolet wavelength.

The active layer 126 may have any one of a single well structure, a multi-well structure, a single quantum well structure, a multi quantum well (MQW) structure, a quantum dot structure, or a quantum wire structure, and the active layer 126 The structure is not limited to this.

The active layer 126 may include a plurality of well layers (not shown) and a barrier layer (not shown). The well layer and the barrier layer may have a composition formula of In _x2 Al _y2 Ga _{1 -x2- y2} N (0≤x2≤1, 0<y2≤1, 0≤x2+y2≤1). The aluminum composition of the well layer may vary depending on the wavelength of light emission. As the aluminum composition increases, the wavelength emitted from the well layer can become shorter.

The second conductive semiconductor layer 127 is formed on the active layer 126 and may be implemented with a compound semiconductor such as group III-V or group II-VI, and the second conductive semiconductor layer 127 has a second Dopants may be doped.

The second conductive semiconductor layer 127 is a semiconductor material with a composition formula of In _x5 Al _y2 Ga _{1 -x5- y2} N (0≤x5<1, 0<y2≤1, 0≤x5+y2≤1) or AlGaN. , AlN, and InAlGaN. When the second dopant is a p-type dopant such as Mg, Zn, Ca, Sr, Ba, etc., the second conductive semiconductor layer 127 doped with the second dopant may be a p-type semiconductor layer.

The light emitting structure 120 may include a plurality of light emitting units 120a and 120b disposed on the first conductive semiconductor layer 124. The plurality of light emitting units 120a and 120b spaced apart from each other may include an active layer 126 and a second conductive semiconductor layer 127. That is, the active layers 126 divided into multiple pieces may be spaced apart, and the second conductive semiconductor layer 127 may be disposed on the multiple active layers 126, respectively.

When the light emitting structure 120 generates ultraviolet light, since it has a high band gap energy, the current dispersion characteristics of the light emitting structure 120 may be poor and the effective light emitting area may be small. In addition, since most of the ultraviolet light generated in the active layer 126 is TM mode emission, which emits light from the side, it may be desirable to expose the side of the active layer 126 as much as possible. Accordingly, when the plurality of light emitting units 120a and 120b are spaced apart, the side perimeter of the active layer 126 can be increased.

The area of the light emitting portion may be 50% to 90% of the maximum area of the chip. If the area is less than 50%, the light emitting area may become smaller and the light emitting efficiency may decrease. Additionally, when the area becomes larger than 90%, the area of the first electrode 142 becomes smaller and the luminous efficiency may decrease. Accordingly, the diameter of each active layer 126 can be appropriately adjusted according to the number of light emitting units within a range that satisfies the above area range of the light emitting units.

The first electrode 142 may be disposed on the first conductive semiconductor layer 124, and the second electrode 146 may be disposed on the second conductive semiconductor layer 127.

The first electrode 142 and the second electrode 146 may be ohmic electrodes. The first electrode 142 and the second electrode 146 are made of indium tin oxide (ITO), indium zinc oxide (IZO), indium zinc tin oxide (IZTO), indium aluminum zinc oxide (IAZO), and indium gallium zinc oxide (IGZO). ), IGTO (indium gallium tin oxide), AZO (aluminum zinc oxide), ATO (antimony tin oxide), GZO (gallium zinc oxide), IZON (IZO Nitride), AGZO (Al-Ga ZnO), IGZO (In-Ga ZnO), ZnO, IrOx, RuOx, NiO, RuOx/ITO, Ni/IrOx/Au, or Ni/IrOx/Au/ITO, Ag, Ni, Cr, Ti, Al, Rh, Pd, Ir, Sn, In, It may be formed including at least one of Ru, Mg, Zn, Pt, Au, and Hf, but is not limited to these materials. By way of example, the first electrode 142 may have a plurality of metal layers (eg, Cr/Al/Ni), and the second electrode 146 may be ITO.

The plurality of light emitting units 120a and 120b include a first light emitting unit 120a vertically overlapping with the first pad 171 and a second light emitting unit 120b vertically overlapping with the second pad 172. It can be included. When the area of the second pad 172 is larger than the area of the first pad 171, the number of second light emitting units 120b may be greater than that of the first light emitting units 120a. Generally, a relatively large amount of heat is generated in the P semiconductor layer, so the heat dissipation effect can be improved by increasing the area of the second pad 172.

The area of the first pad 171 may be 10% to 30% of the area of the second pad 172. If the area of the first pad 171 is smaller than 10% of the area of the second pad 172, the area of the first pad 171 becomes small, making it difficult to inject sufficient current. Additionally, if the area of the first pad 171 is larger than 30% of the area of the second pad 172, the area of the second pad 172 may become small and heat dissipation performance may deteriorate.

The first light emitting unit 120a may not emit light because it is not electrically connected to the second pad 172. Therefore, it may be advantageous to have a relatively small number of first light emitting units 120a. Hereinafter, the number of first light emitting units 120a will be described as one, but the number is not limited thereto.

The plurality of light emitting units 120a and 120b may have a circular shape. However, the shape of the plurality of light emitting units 120a and 120b may be modified in various ways. For example, the shape of the light emitting unit may be a polygonal shape. That is, various shapes can be applied to increase the side perimeter of the active layer 126.

The first electrode 142 may include an extension portion 142a disposed on the first light emitting portion 120a. The extension portion 142a may be electrically connected to the first electrode 142 disposed on the first conductive semiconductor layer 124. The extension portion 142a may be defined as an area of the first electrode 142 that overlaps the first light emitting portion 120a in the vertical direction. The extension portion 142a may be disposed on the upper surface of , but is not necessarily limited thereto.

Referring to FIG. 3A, holes may be formed in the first electrode 142 surrounding the plurality of second light emitting units 120b. Additionally, the extension portion 142a may be formed entirely on the first light emitting portion 120a.

Referring again to FIG. 2 , the insulating layer 160 may be disposed on the first electrode 142 and the second electrode 146 . The insulating layer 160 may be formed by selecting at least one from the group consisting of SiO ₂ , SixOy, Si ₃ N ₄ , SixNy, SiOxNy, Al ₂ O ₃ , TiO ₂ , AlN, etc. When the insulating layer 160 includes a reflective material, light emitted from the insulating layer 160 may be reflected toward the substrate 110.

The first pad 171 may penetrate the insulating layer 160 and contact the extension portion 142a. Accordingly, the current injected into the first pad 171 may be injected into the first conductive semiconductor layer 124 through the extension portion 142a.

The second pad 172 may penetrate the insulating layer 160 and contact the plurality of second electrodes 146. Accordingly, the current injected into the second pad 172 may be injected into the second conductive semiconductor layer 127 through the plurality of second electrodes 146.

If the first pad 171 is formed without the first light emitting part 120a, the first pad 171 needs to be formed relatively thicker in order to match the height with the second pad 172. Therefore, there is a problem that the process becomes complicated. However, according to the embodiment, the first pad 171 is disposed on the first light emitting unit 120a having the same height as the second light emitting unit 120b, so the first pad 171 does not have to be made thick on purpose. The first pad 171 and the second pad 172 may have the same height.

Referring to FIG. 3B, there may be a plurality of first light emitting units 120a perpendicular to the first pad 171. As described above, the area of the first pad 171 may be 10% to 30% of the area of the second pad 172. That is, considering heat dissipation and current injection efficiency through the first pad 171, the first pad 171 and the second pad 172 need to have an appropriate area ratio. Accordingly, since the first pad 171 must secure more than a certain area, a plurality of first light emitting units 120a may overlap with the first pad 171. Accordingly, the extension portion 142a of the first electrode 142 may be arranged to cover the plurality of first light emitting portions 120a.

FIG. 4A is a first modified example of FIG. 1, and FIG. 4B is a second modified example of FIG. 2.

Referring to FIG. 4A, the plurality of light emitting units 120a and 120b may have a polygonal shape. For example, the plurality of light emitting units 120a and 120b may have a square shape. When the plurality of light emitting units 120a and 120b are square in shape, the area of the light emitting units can be maximized. Accordingly, since the light emitting area increases, the light emitting efficiency can be improved. However, it is not necessarily limited to this, and the shape of the light emitting unit may be modified in various ways. For example, the plurality of light emitting units 120a and 120b may have a pentagonal or hexagonal shape.

Referring to FIG. 4B, the plurality of light emitting units 120a and 120b have small diameters and can be arranged in large numbers. The number of light emitting units disposed closest to any one light emitting unit may be six. By connecting the centers of adjacent light emitting units, a hexagonal shape (E1) can be formed. In this case, the spacing of the light emitting parts can be arranged closely, so the light emitting efficiency can be improved. However, it is not necessarily limited to this, and the number of light emitting units arranged closest to each other may be appropriately modified. Illustratively, the number of light emitting units disposed closest to any one light emitting unit may be 4, 8, or 10.

Additionally, in consideration of the diffusion distance of the current injected from the first electrode 142, the plurality of light emitting units 120a and 120b may include at least one light emitting unit with a different upper surface area to have a uniform current density.

The diameter of the plurality of light emitting units 120a and 120b may be 30 μm to 70 μm. In the case of ultraviolet light-emitting devices, the aluminum composition of each semiconductor layer may be more than 40%, so current dispersion efficiency may be relatively poor. Therefore, when the diameter of the plurality of pieces is larger than 70㎛, the current may not be distributed to the edge portion and may not emit light or may emit light only weakly. In addition, when the diameter of the light emitting part is smaller than 30㎛, as the number of light emitting parts increases, the area from which the light emitting part is removed also increases, which may reduce luminous efficiency.

While all of the second light emitting units 120b participate in light emission, the first light emitting unit 120a may not participate in light emission. Accordingly, the first light emitting portion 120a may be manufactured to be larger than 30㎛ to 70㎛.

However, it is not necessarily limited to this, and as will be described later, the first light emitting unit 120a overlapping the first pad 171 may also emit light using a channel electrode or the like. In this case, the diameter of the first light emitting unit 120a and the diameter of the second light emitting unit 120b may be the same.

Figure 5 is a cross-sectional view of a light emitting device according to a second embodiment of the present invention, and Figure 6 is a cross-sectional view taken along the line B-B of Figure 5.

Referring to FIGS. 5 and 6 , the light emitting structure 120 may include a plurality of light emitting units 120a and 120b disposed on the first conductivity type semiconductor layer 124. Each of the plurality of light emitting units 120a and 120b may include an active layer 126 and a second conductive semiconductor layer 127. That is, the active layers 126 divided into multiple pieces may be spaced apart from each other, and the divided second conductive semiconductor layers 127 may be disposed on the multiple active layers 126 .

The plurality of light emitting units 120a and 120b include a first light emitting unit 120a vertically overlapping with the first pad 171 and a plurality of second light emitting units 120b vertically overlapping with the second pad 172. ) may include. When the area of the second pad 172 is larger than the area of the first pad 171, the number of second light emitting units 120b may be greater than that of the first light emitting units 120a.

The first electrode 142 may be disposed on the first conductive semiconductor layer 124, and the second electrode 146 may be disposed on the second conductive semiconductor layer 127. At this time, the first electrode 142 may include an extension portion 142a disposed on the first light emitting portion 120a. By way of example, the first electrode 142 may have a plurality of metal layers (eg, Cr/Al/Ni), and the second electrode 146 may be ITO, but is not necessarily limited thereto.

The first pad 171 may penetrate the insulating layer 160 and be electrically connected to the extension portion 142a, and the second pad 172 may penetrate the insulating layer 160 to form a plurality of second electrodes 146. can be electrically connected to.

To prevent short circuit, the first pad 171 and the second pad 172 may be spaced apart at a predetermined interval. However, if the gap between the first pad 171 and the second pad 172 increases, the short circuit prevention effect may be improved, but the light emitting area may be relatively reduced. Therefore, it is necessary to prevent short circuit while arranging the first pad 171 and the second pad 172 as close as possible.

According to an embodiment, a partition 173 may be disposed between the first light emitting unit 120a and the second light emitting unit 120b. That is, the partition 173 may be disposed between the first pad 171 and the second pad 172.

According to this structure, when attaching a light emitting device to a circuit board (not shown), a short circuit can be prevented by the partition wall 173. To this end, the ratio between the height of the top surface of the first pad 171 and the height of the insulating layer 160 disposed on the partition wall 173 may be 1:0.8 to 1:1. If the height ratio is less than 1:0.8, the partition wall 173 may not effectively block the solder applied to the circuit board, which may cause a short circuit. If the height ratio is greater than 1:1 (e.g., 1:1.2), the partition wall 173 This protrusion may cause adhesion failure when soldering to the circuit board.

At this time, the distance W13 between the partition wall 173 and the first pad 171 may be about 5㎛ to 15㎛, and the distance W12 between the partition wall 173 and the second pad 172 may be about 5㎛. It may be ㎛ to 15㎛. Additionally, the width W11 of the partition wall 173 may be 3 μm to 10 μm. Accordingly, the distance W14 between the first pad 171 and the second pad 172 can be placed as close as 20 μm to 30 μm, thereby increasing the light emitting area.

The partition wall 173 may include the same material as the first electrode 142 and/or the second electrode 146. For example, the first layer 173a of the partition 173 may be formed when forming the first electrode 142, and the second layer 173b of the partition 173 may be formed when forming the second electrode 146. . Accordingly, the first layer 173a may be the same as the thickness of the first electrode 142 layer, and the second layer may be the same as the thickness of the second electrode 146 layer.

However, it is not necessarily limited to this, and the first layer 173a of the partition 173 forms a part of the second electrode 146, and the second layer 173b of the partition 173 forms a part of the first electrode 142. ) can form part of it when formed.

The third layer 173c of the partition wall 173 can be formed through an additional process. The third layer 173c of the partition wall 173 may include a metal material or a polymer resin.

Alternatively, the partition wall 173 may be disposed on the dummy light emitting unit. That is, it is possible to form a light emitting part that acts as a dummy, such as the first light emitting part 120a, and then form a partition thereon.

Figure 7 is a plan view of a light emitting device according to a third embodiment of the present invention, and Figure 8 is a cross-sectional view taken along the line C-C of Figure 7.

Referring to FIG. 7 , the light emitting structure 120 may include a plurality of light emitting units 120b disposed on the first conductive semiconductor layer 124. Each of the plurality of light emitting units 120b may include an active layer 126 and a second conductive semiconductor layer 127. That is, the active layers 126 divided into multiple pieces may be spaced apart from each other, and the divided second conductive semiconductor layers 127 may be disposed on the multiple active layers 126 .

The plurality of light emitting units 120b may overlap in the vertical direction with the second pad 172 but may not overlap in the vertical direction with the first pad 171. That is, the light emitting part may be removed in the area where the first pad 171 is disposed, and the first conductivity type semiconductor layer 124 may be exposed.

The first electrode 142 may be disposed on the first conductive semiconductor layer 124, and the second electrode 146 may be disposed on the second conductive semiconductor layer 127.

The first pad 171 may penetrate the insulating layer 160 and be electrically connected to the first electrode 142, and the second pad 172 may penetrate the insulating layer 160 to form a plurality of second electrodes 146. ) can be electrically connected to. At this time, the configuration of the partition described in FIGS. 5 and 6 may be included.

FIG. 9 is a plan view of a light emitting device according to a fourth embodiment of the present invention, FIG. 10 is a cross-sectional view in the D-D direction of FIG. 9, FIG. 11 is a cross-sectional view in the E-E direction of FIG. 9, and FIG. 12 is a plan view of the first electrode and the active layer. am.

Referring to FIGS. 9 and 10 , the light emitting structure 120 may include a plurality of light emitting units 120a and 120b disposed on the first conductive semiconductor layer 124. Each of the plurality of light emitting units 120a and 120b may include an active layer 126 and a second conductive semiconductor layer 127. That is, the active layers 126 divided into multiple pieces may be spaced apart from each other, and the divided second conductive semiconductor layers 127 may be disposed on the multiple active layers 126 .

The plurality of light emitting units 120a and 120b include a first light emitting unit 120a vertically overlapping with the first pad 171 and a second light emitting unit 120b vertically overlapping with the second pad 172. It can be included. When the area of the second pad 172 is the same as that of the first pad 171, the number of first light emitting units 120a and the second light emitting units 120b may be the same.

The first electrode 142 may be disposed on the first conductive semiconductor layer 124, and the second electrode 146 may be disposed on the second conductive semiconductor layer 127. By way of example, the first electrode 142 may have a plurality of metal layers (eg, Cr/Al/Ni), and the second electrode 146 may be ITO, but is not necessarily limited thereto.

The first insulating layer 161 may be disposed on the first electrode 142 and the second electrode 146. The insulating layer 160 may be disposed on the first electrode 142 and the second electrode 146. The insulating layer 160 may be formed by selecting at least one from the group consisting of SiO ₂ , SixOy, Si ₃ N ₄ , SixNy, SiOxNy, Al ₂ O ₃ , TiO ₂ , AlN, etc. When the insulating layer 160 includes a reflective material, light emitted from the insulating layer 160 may be reflected toward the substrate 110.

The channel electrode 147 may penetrate the first insulating layer 161 to electrically connect the first light emitting unit 120a and the second light emitting unit 120b. Accordingly, the current injected through the second pad 172 may be injected into the first light emitting unit 120a and the second light emitting unit 120b.

A second insulating layer 162 may be disposed on the channel electrode 147. The second insulating layer 162 may be made of the same material as the first insulating layer 161, but is not necessarily limited thereto. The second insulating layer 162 may be disposed only on the channel electrode, but is not necessarily limited thereto, and may be formed entirely on the first insulating layer 161 and the channel electrode.

The second insulating layer 162 may be made of Si _x N _y to improve the reliability of the light emitting device. In this case, the second insulating layer 162 may be made of a different material from the first insulating layer 161. For example, the first insulating layer 161 may be made of a Si _x O _y material, and the second insulating layer 162 may be made of a Si _x N _y material. In this case, when a reflective layer (not shown) is disposed between the first insulating layer 161 and the second insulating layer 162, light extraction efficiency is achieved by the light-transmitting first insulating layer 161 and the reflective layer (not shown). While improving, the reliability of the light emitting device by the second insulating layer 162 can be improved. Additionally, when considering the refractive index for reflection, SiO _x N _y , TiO _{2 ,} materials, etc. may be applied to function as a Distribute Bragg Reflector (DBR).

Referring to FIG. 11, the first pad 171 may penetrate the first insulating layer 161 and the second insulating layer 162 and be electrically connected to the first electrode 142. Additionally, the second pad 172 may be electrically connected to a plurality of second electrodes 146 and the channel electrode 147.

Referring to FIG. 12, the active layers 126 may be spaced apart from each other, and the first electrode 142 may be disposed entirely in the remaining area excluding the area where the active layer 126 is disposed. The current injected through the first pad 171 may uniformly distribute the current to the first conductivity type semiconductor layer 124.

FIG. 13 is a top view of a light emitting device according to a fifth embodiment of the present invention, FIG. 14 is a cross-sectional view in the direction F-F of FIG. 13, FIG. 15 is a top view of the first electrode and the active layer, and FIG. 16 is a view of FIG. 13 from another direction. This is a cross-sectional view.

13 and 14, the plurality of light emitting units 120a and 120b overlap in the vertical direction with the first light emitting unit 120a and the second pad 172, which overlap in the vertical direction with the first pad 171. It may include a second light emitting unit 120b. When the area of the second pad 172 is larger than the area of the first pad 171, the number of second light emitting units 120b may be greater than the number of first light emitting units 120a. Generally, a relatively large amount of heat is generated in the P semiconductor layer, so the heat dissipation effect can be improved by increasing the area of the second pad 172.

The first electrode 142 may be disposed on the first conductive semiconductor layer 124, and the second electrode 146 may be disposed on the second conductive semiconductor layer 127. By way of example, the first electrode 142 may have a plurality of metal layers (eg, Cr/Al/Ni), and the second electrode 146 may be ITO, but is not necessarily limited thereto.

The first insulating layer 161 may be disposed on the first electrode 142 and the second electrode 146. The insulating layer 160 may be disposed on the first electrode 142 and the second electrode 146. The insulating layer 160 may be formed by selecting at least one from the group consisting of SiO ₂ , SixOy, Si ₃ N ₄ , SixNy, SiOxNy, Al ₂ O ₃ , TiO ₂ , AlN, etc. When the insulating layer 160 includes a reflective material, light emitted from the insulating layer 160 may be reflected toward the substrate 110.

A channel electrode (not shown) may penetrate the first insulating layer 161 to electrically connect the first light emitting unit 120a and the second light emitting unit 120b (same structure as in FIG. 10). Accordingly, the current injected through the second pad 172 may be injected into the first light emitting unit 120a and the second light emitting unit 120b.

A second insulating layer 162 may be disposed on the first insulating layer 161. The second insulating layer 162 may be made of the same material as the first insulating layer 161, but is not necessarily limited thereto. The second insulating layer 162 may be disposed only on the channel electrode, but is not necessarily limited thereto, and may be formed entirely on the first insulating layer 161 and the channel electrode.

The first pad 171 may penetrate the first insulating layer 161 and the second insulating layer 162 and be electrically connected to the first electrode 142. Referring to FIG. 15, the active layers 126 may be spaced apart from each other, and the first electrode 142 may be disposed entirely in the remaining area excluding the area where the active layer 126 is disposed. The current injected through the first pad 171 may uniformly distribute the current to the first conductivity type semiconductor layer 124.

Referring to FIG. 16, the channel electrode 147 may penetrate the first insulating layer 161 and electrically connect the first light emitting unit 120a and the second light emitting unit 120b. Accordingly, the current injected through the second pad 172 may be injected into the first light emitting unit 120a and the second light emitting unit 120b.

A second insulating layer 162 may be disposed on the channel electrode 147. The second insulating layer 162 may be made of the same material as the first insulating layer 161, but is not necessarily limited thereto. The second insulating layer 162 may be disposed only on the channel electrode, but is not necessarily limited thereto, and may be formed entirely on the first insulating layer 161 and the channel electrode.

According to the embodiment, the first insulating layer 161 and the second insulating layer 162 are stacked, so there is an advantage in efficiently blocking external contaminants. In addition, the first insulating layer 161 and the second insulating layer 162 can be made of different materials to perform a reflection function using a difference in refractive index. In this case, ultraviolet light generated in the active layer 126 is reflected and light extraction efficiency may be improved.

The second insulating layer 162 may be made of Si _x N _y to improve the reliability of the light emitting device. In this case, the second insulating layer 162 may be made of a different material from the first insulating layer 161. For example, the first insulating layer 161 may be made of a Si _x O _y material, and the second insulating layer 162 may be made of a Si _x N _y material. In this case, when a reflective layer (not shown) is disposed between the first insulating layer 161 and the second insulating layer 162, light extraction efficiency is achieved by the light-transmitting first insulating layer 161 and the reflective layer (not shown). While improving, the reliability of the light emitting device by the second insulating layer 162 can be improved. Additionally, when considering the refractive index for reflection, SiO _x N _y , TiO _{2 ,} materials, etc. may be applied to function as a Distribute Bragg Reflector (DBR).

Figure 17 is a plan view of a light emitting device according to a sixth embodiment of the present invention, and Figure 18 is a plan view of a light emitting device according to a seventh embodiment of the present invention.

Referring to FIG. 17, the light emitting structure 120 may include a plurality of light emitting units 120a and 120b. The plurality of light emitting units 120a and 120b include a first light emitting unit 120a vertically overlapping with the first pad 171 and a second light emitting unit 120b vertically overlapping with the second pad 172. It can be included.

At this time, the first pad 171 may be disposed between two second pads 172 facing each other. For example, the second pads 172 may have a triangular shape and be arranged to face each other, and the line-shaped first pad 171 may be arranged between the second pads 172 .

At this time, the first light emitting unit 120a and the second light emitting unit 120b may be connected to each other by a channel electrode. According to this structure, both the first light emitting unit 120a and the second light emitting unit 120b can emit light, so light emission efficiency can be improved.

Referring to FIG. 18 , the light emitting structure 120 may include a plurality of light emitting units 120a and 120b disposed on the first conductivity type semiconductor layer 124. The plurality of light emitting units 120a and 120b include a first light emitting unit 120a vertically overlapping with the first pad 171 and a second light emitting unit 120b vertically overlapping with the second pad 172. It can be included.

At this time, the plurality of first light emitting units 120a overlapping with the second pad 172 may have different diameters. Exemplarily, the plurality of first light emitting units 120a may include a 1-1 light emitting unit 120b-1 with a relatively large diameter and a 1-2 light emitting unit 120b-2 with a relatively small diameter. there is. According to this configuration, the gap between light emitting units can be narrowed, and thus the light emitting area can be increased.

The shapes of the 1-1 light emitting unit 120b-1 and the 1-2 light emitting unit 120b-2 may be different. For example, the 1-1 light emitting unit 120b-1 may have a circular shape, and the 1-2 light emitting unit 120b-2 may have a cross shape. That is, the shape of the light emitting unit can be modified in various ways to expand the light emitting area.

Figure 19 is a cross-sectional view of a light emitting device package according to an embodiment of the present invention.

Referring to FIG. 19, a light emitting device package according to an embodiment may include a body 1 and a light emitting device disposed inside the body 1. The light emitting device may include all of the above-described configurations.

The body 1 may include a cavity 2 in which a light emitting device is disposed, but is not necessarily limited thereto. For example, the body 1 may have a substrate shape.

A circuit pattern electrically connected to the light emitting device 100 may be disposed inside the body 1. However, it is not necessarily limited to this, and the body 1 itself may be made of a conductive material. For example, the body 1 may be made of aluminum. A light transmitting substrate 3 may be disposed on the body 1. The light transmitting substrate 3 may include various materials capable of transmitting ultraviolet light. For example, the light transmitting substrate may be made of SUS, but is not necessarily limited thereto.

Light emitting devices can be applied to various types of light source devices. For example, the light source device may include a sterilizing device, a curing device, a lighting device, a display device, and a vehicle lamp. In other words, the light emitting device can be applied to various electronic devices that are placed in a case and provide light.

The sterilizing device is equipped with a light emitting device according to the embodiment and can sterilize a desired area. The sterilizing device may be applied to household appliances such as water purifiers, air conditioners, and refrigerators, but is not necessarily limited thereto. In other words, the sterilization device can be applied to a variety of products that require sterilization (e.g., medical devices).

Exemplarily, a water purifier may be equipped with a sterilizing device according to an embodiment to sterilize circulating water. The sterilizing device may be placed at a nozzle or outlet through which water circulates and irradiate ultraviolet rays. At this time, the sterilizing device may include a waterproof structure.

The curing device is equipped with a light emitting device according to the embodiment and can cure various types of liquids. Liquid may be the broadest concept that includes all various substances that harden when irradiated with ultraviolet rays. For example, the curing device can cure various types of resin. Alternatively, the curing device may be applied to harden beauty products such as nail polish.

The lighting device may include a light source module including a substrate and the light emitting device of the embodiment, a heat dissipation unit that dissipates heat from the light source module, and a power supply unit that processes or converts an electrical signal provided from the outside and provides the light source module to the light source module. Additionally, the lighting device may include a lamp, head lamp, or street lamp.

The display device may include a bottom cover, a reflector, a light emitting module, a light guide plate, an optical sheet, a display panel, an image signal output circuit, and a color filter. The bottom cover, reflector, light emitting module, light guide plate, and optical sheet may constitute a backlight unit.

The reflector is disposed on the bottom cover, and the light emitting module can emit light. The light guide plate is disposed in front of the reflector and guides the light emitted from the light emitting module to the front, and the optical sheet includes a prism sheet, etc. and may be disposed in front of the light guide plate. A display panel may be disposed in front of the optical sheet, an image signal output circuit may supply an image signal to the display panel, and a color filter may be disposed in front of the display panel.

When used as a backlight unit of a display device, the light emitting element can be used as an edge-type backlight unit or a direct-type backlight unit.

Although the above description focuses on the examples, this is only an example and does not limit the present invention, and those skilled in the art will be able to You will see that various variations and applications are possible. For example, each component specifically shown in the examples can be modified and implemented. And these variations and differences in application should be construed as being included in the scope of the present invention as defined in the appended claims.

Claims (20)

a plurality of light emitting units spaced apart from each other on the first conductive semiconductor layer;
a first electrode electrically connected to the first conductive semiconductor layer;
a plurality of second electrodes electrically connected to the plurality of light emitting units;
an insulating layer disposed on the first electrode and the plurality of second electrodes;
a first pad and a second pad disposed on the insulating layer; and
It includes a partition wall disposed between the first pad and the second pad,
The plurality of light emitting units each include an active layer and a second conductivity type semiconductor layer,
The first electrode is disposed surrounding at least one light emitting unit among the plurality of light emitting units,
The second pad penetrates the insulating layer and is electrically connected to the plurality of second electrodes,
The first pad is electrically connected to the first electrode,
The insulating layer is disposed on the partition wall,
A light emitting device wherein the height of the top surface of the insulating layer is less than or equal to the height of the top surface of the first pad and the height of the top surface of the second pad.

According to paragraph 1,
The plurality of light emitting units include at least one first light emitting unit vertically overlapping with the first pad and a plurality of second light emitting units vertically overlapping with the second pad,
The first electrode includes an extension portion extending onto the at least one first light emitting portion,
The first pad is a light emitting device that penetrates the insulating layer and is electrically connected to the extension portion.
According to paragraph 2,
A light emitting device in which an area of the first light emitting unit is larger than an area of the plurality of second light emitting units.
According to paragraph 1,
A light emitting device wherein the area of the first pad is 10% to 30% of the area of the second pad.
According to paragraph 1,
A light emitting device wherein the plurality of light emitting units have a circular or polygonal shape.
According to clause 5,
The plurality of light emitting units have a circular shape,
A light emitting device wherein the plurality of light emitting parts have a diameter of 30㎛ to 70㎛.
According to clause 6,
A light emitting device wherein the aluminum composition of the first conductive semiconductor layer, the active layer, and the second conductive semiconductor layer is 40% or more.
According to clause 5,
A light emitting device in which the sizes of the plurality of light emitting parts are different from each other.
According to paragraph 1,
A light emitting device wherein the total area of the active layer disposed in the plurality of light emitting units is 50% to 90% of the total area of the light emitting device.
According to clause 9,
The aluminum composition of the first conductive semiconductor layer, the active layer, and the second conductive semiconductor layer is 40% or more,
A light emitting device wherein the plurality of light emitting parts have a diameter of 30㎛ to 70㎛.
According to clause 9,
The active layer is a light emitting device that emits light with a main peak at 100 nm to 310 nm.
delete According to paragraph 1,
A light emitting device wherein a height ratio between the upper surface of the first pad and the upper surface of the insulating layer disposed on the partition is 1:0.8 to 1:1.
delete A light emitting structure comprising a plurality of light emitting units spaced apart from each other on a first conductive semiconductor layer, wherein the plurality of light emitting units each include an active layer and a second conductive semiconductor layer disposed on the active layer;
a first electrode disposed on the first conductive semiconductor layer;
a plurality of second electrodes disposed on the plurality of light emitting units;
a first insulating layer disposed on the first electrode and the plurality of second electrodes;
a second insulating layer disposed on the first insulating layer;
a channel electrode disposed between the first insulating layer and the second insulating layer;
a first pad electrically connected to the first electrode; and
It includes a second pad electrically connected to the second electrode,
The plurality of light emitting units include a first light emitting unit that overlaps the first pad in a vertical direction and a second light emitting unit that overlaps the second pad in a vertical direction,
The channel electrode electrically connects the first light emitting unit and the second light emitting unit,
The second insulating layer is a light emitting device disposed between the channel electrode and the first pad.
According to clause 15,
A light emitting device wherein the area of the first pad is 10% to 30% of the area of the second pad.
According to clause 15,
A light emitting device wherein the second pad has the same area as the first pad.
According to clause 15,
The active layer is a light emitting device that emits light with a main peak at 100 nm to 310 nm.
According to clause 15,
The first pad is a light emitting device that penetrates the first insulating layer and the second insulating layer and is electrically connected to the first electrode.
body;
Includes a light emitting element disposed on the body,
The light emitting device is,
a plurality of light emitting units spaced apart from each other on the first conductive semiconductor layer;
a first electrode electrically connected to the first conductive semiconductor layer;
a plurality of second electrodes electrically connected to the plurality of light emitting units;
an insulating layer disposed on the first electrode and the plurality of second electrodes;
a first pad and a second pad disposed on the insulating layer; and
It includes a partition wall disposed between the first pad and the second pad,
The plurality of light emitting units each include an active layer and a second conductivity type semiconductor layer,
The first electrode is disposed surrounding at least one light emitting unit among the plurality of light emitting units,
The second pad penetrates the insulating layer and is electrically connected to the plurality of second electrodes,
The first pad is electrically connected to the first electrode,
The insulating layer is disposed on the partition wall,
A light emitting device package wherein the height of the top surface of the insulating layer is less than or equal to the height of the top surface of the first pad and the height of the top surface of the second pad.

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