KR102306802B1 - Light emitting device - Google Patents

Abstract

A light emitting device is disclosed. The light emitting device includes: a substrate; a light emitting unit positioned on the substrate and including a light emitting device and a wavelength conversion unit positioned on the light emitting device; a bonding layer positioned between the light emitting unit and the substrate and bonding the light emitting unit to the substrate; and a sidewall portion surrounding a side surface of the light emitting unit and in contact with the side surface of the light emitting unit, wherein the bonding layer includes a metal sintered body including metal particles.

Description

Light Emitting Device {LIGHT EMITTING DEVICE}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light emitting device, and more particularly, to a light emitting device having high heat dissipation efficiency and low defect rate and excellent reliability.

Light emitting diodes are inorganic semiconductor devices that emit light generated by recombination of electrons and holes, and are recently used in various fields such as displays, automobile lamps, and general lighting. Since the light emitting diode has a long lifespan, low power consumption, and fast response speed, a light emitting device including the light emitting diode is expected to replace the conventional light source.

The light emitting diode may be classified into a horizontal light emitting diode, a flip-chip type light emitting diode, and a vertical light emitting diode according to the position and structure of the electrode. Among them, the flip-chip type light emitting diode has an electrode positioned thereunder, and the electrode can be mounted on a separate substrate to be used. Accordingly, the flip-chip type light emitting diode is widely used in high power light emitting devices because of its excellent horizontal current distribution and excellent heat dissipation efficiency.

In order to mount the flip-chip type light emitting diode on a separate substrate, a process of bonding the light emitting diode to the substrate using an electrically conductive material is required. Conventionally, as a method of bonding the flick-type light emitting diode to the substrate, a conductive paste is used, eutectic bonding is used, or an Au bump ball bonding method is used.

When a conductive paste is used, spreading occurs in the bonding process due to the viscosity of the paste, and the n-electrode and the p-electrode are electrically connected to each other, thereby causing an electrical short of the light emitting diode. In addition, in the case of eutectic bonding, pores may be generated in the eutectic bonded structure, which may cause reliability problems. In addition, in the case of Au bump ball bonding, the contact area is relatively small, so the heat dissipation efficiency is low, and the mechanical reliability is low.

SUMMARY OF THE INVENTION An object of the present invention is to provide a light emitting device having high heat dissipation efficiency and high reliability.

A light emitting device according to an aspect of the present invention includes: a substrate; a light emitting unit positioned on the substrate and including a light emitting device and a wavelength conversion unit positioned on the light emitting device; a bonding layer positioned between the light emitting unit and the substrate and bonding the light emitting unit to the substrate; and a sidewall portion surrounding a side surface of the light emitting unit and in contact with the side surface of the light emitting unit, wherein the bonding layer includes a metal sintered body including metal particles.

The metal particles may include Ag particles.

The light emitting device may be positioned on a lower surface thereof, and may include a first pad electrode and a second pad electrode spaced apart from each other.

Furthermore, the bonding layer may include a first bonding layer and a second bonding layer, the first bonding layer may cover a lower surface and at least a portion of a side surface of the first pad electrode, and the second bonding layer may include A lower surface and at least a portion of a side surface of the second pad electrode may be covered.

In addition, each of the first pad electrode and the second pad electrode may include a side surface where the first pad electrode and the second pad electrode face each other, and one side of the first bonding layer is the first pad electrode. may be positioned in parallel with the opposite side surface of the second bonding layer, and one side of the second bonding layer may be positioned parallel to the opposite side surface of the second pad electrode.

The first bonding layer may cover side surfaces other than the opposite side surface of the first pad electrode, the other side surfaces of the first bonding layer may be parallel to the side surface of the light emitting device, and the second bonding layer may cover side surfaces other than the opposite side surface of the second pad electrode, and the other side surfaces of the second bonding layer may be positioned parallel to the side surface of the light emitting device.

In some embodiments, the bonding layer may include a first bonding layer and a second bonding layer, the first bonding layer covering the first pad electrode, and the second bonding layer covering the second pad electrode. can cover

The bonding layer may have a thickness of 10 to 30 μm.

Each of the light emitting part and the bonding layer may be formed in plurality, and the plurality of light emitting units may be bonded to the substrate by the plurality of bonding layers.

A light emitting device according to another aspect of the present invention includes: a substrate; a first light emitting unit positioned on the substrate and including a first light emitting device and a first wavelength conversion unit positioned on the light emitting device; a second light emitting unit located on the substrate, spaced apart from the first light emitting unit, and including a second light emitting device and a second wavelength converting unit disposed on the light emitting device; a first bonding layer positioned between the first light emitting part and the substrate; a second bonding layer positioned between the second light emitting part and the substrate; and a sidewall portion surrounding side surfaces of the first and second light emitting units and in contact with the side surfaces of the first and second light emitting units, wherein the first light emitting unit and the second light emitting unit emit light having different peak wavelengths. and the first and second bonding layers each include a metal sintered body including metal particles.

The metal particles may include Ag particles.

The substrate may include first to fourth electrodes, the first and second electrodes are electrically connected to the first light emitting part, and the third and fourth electrodes are electrically connected to the second light emitting part. can

The first to fourth electrodes may be insulated from each other, and each of the first to fourth electrodes may be exposed on the outer surface of the substrate.

The first light emitting unit may emit white light.

The second light emitting unit may emit amber color light.

Each of the first and second light emitting devices may include pad electrodes positioned on a lower surface thereof.

Furthermore, the first bonding layer may cover lower surfaces and at least some side surfaces of the pad electrodes positioned under the first light emitting device, and the second bonding layer may include lower surfaces of the pad electrodes positioned under the second light emitting device. and at least part of the side surfaces.

A side surface of the first bonding layer may be parallel to a side surface of the first light emitting device, and a side surface of the second bonding layer may be parallel to a side surface of the second light emitting device.

According to the present invention, by disclosing a light emitting device including a bonding layer including a metal particle sintered body, a light emitting device having excellent heat dissipation efficiency and effectively preventing an electric short can be provided, thereby providing a highly reliable light emitting device.

1 is a cross-sectional view for explaining a light emitting device according to an embodiment of the present invention.
2A and 2B are enlarged cross-sectional views for explaining a bonding layer of a light emitting device according to other embodiments of the present invention.
3 is a cross-sectional view for explaining a light emitting device according to another embodiment of the present invention.
4 to 7 are a perspective view, a plan view, a bottom plan view, and a cross-sectional view for explaining a light emitting device according to another embodiment of the present invention.
8 is a plan view for explaining a light emitting device according to another embodiment of the present invention.
9 is a front view for explaining a vehicle lamp according to another embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The embodiments introduced below are provided as examples so that the spirit of the present invention can be sufficiently conveyed to those skilled in the art to which the present invention pertains. Accordingly, the present invention is not limited to the embodiments described below and may be embodied in other forms. And in the drawings, the width, length, thickness, etc. of the components may be exaggerated for convenience. In addition, when one component is described as being “on” or “on” another component, each component is different from each component, as well as when each component is “immediately above” or “directly on” the other component. It includes cases where there is another component in between. Like reference numerals refer to like elements throughout.

1 is a cross-sectional view illustrating a light emitting device according to an embodiment of the present invention, and FIGS. 2A and 2B are enlarged cross-sectional views illustrating a bonding layer of a light emitting device according to other embodiments of the present invention.

First, referring to FIG. 1 , the light emitting device 10 includes a light emitting unit 100 including a light emitting element 110 and a wavelength conversion unit 120 , a bonding layer 130 , a sidewall unit 300 , and a substrate ( 400) is included. Furthermore, the light emitting device 10 may further include a protection element (not shown).

The substrate 400 may be positioned at the bottom of the light emitting device 10 , and may serve to support the light emitting device 110 and the sidewall portion 300 . The substrate 400 may be an insulating or conductive substrate, or a PCB including a conductive pattern. When the substrate 400 is an insulating substrate, the substrate 400 may include a polymer material or a ceramic material, for example, a ceramic material having excellent thermal conductivity, such as AlN.

In addition, the substrate 400 may include a base 410 , and further include a first electrode 421 and a second electrode 431 . In this case, the base 410 may serve to support the substrate 400 and the electrodes 421 and 431 as a whole, and may include an insulating material to insulate the electrodes 421 and 431 from each other. For example, the base 410 may include a ceramic material such as AlN having excellent thermal conductivity.

The first electrode 421 and the second electrode 431 may be insulated from each other, penetrate the base 410 up and down, and may be exposed on upper and lower portions of the base 410 . Accordingly, the electrodes 421 and 431 may be electrically connected to the light emitting device 110 positioned on the substrate 400 , and may also be electrically connected to an external power source through a portion exposed under the substrate 400 . It may be connected to supply power to the light emitting device 110 .

However, the present invention is not limited thereto, and the first and second electrodes 421 and 431 may have various shapes, and each of the first and second electrodes 421 and 431 may be formed in plurality. have. For example, at least one of the first and second electrodes 421 and 431 may be exposed through the side surface of the base 410 .

The light emitting device 110 may be positioned on the substrate 400 and may include a light emitting structure 111 . In addition, the light emitting device 110 may further include a first pad electrode and a second pad electrode. The light emitting device 110 may be mounted on the substrate 400 by the bonding layer 130 . The structural shape of the light emitting device 110 is not limited, and may be, for example, a flip-chip semiconductor light emitting device in which pad electrodes are positioned on one surface of the light emitting structure 111 .

The light emitting structure 111 may include an n-type semiconductor layer, a p-type semiconductor layer, and an active layer positioned between the n-type semiconductor layer and the p-type semiconductor layer. Accordingly, power is supplied to the first light emitting device 110 . Light can be emitted when supplied.

The bonding layer 130 may be positioned between the light emitting device 110 and the substrate 400 , and may be mounted by bonding the light emitting device 110 to the substrate 400 . Also, the bonding layer 130 may include a first bonding layer 131 and a second bonding layer 133 .

The first and second bonding layers 131 and 133 may be insulated from each other, and may be electrically connected to semiconductor layers having different polarities of the light emitting structure 111 , respectively. Also, the first and second bonding layers 131 and 133 may be disposed on the first electrode 421 and the second electrode 431 of the substrate 400 and may be electrically connected to each other.

The bonding layer 130 may include a material having electrical conductivity, in particular, a metal sintered body. For example, the bonding layer 130 may include an Ag sintered body formed by sintering Ag particles. The bonding layer 130 forms a plurality of Ag sintered body films on the substrate 400 in a portion corresponding to the region where the bonding layer 130 is formed, and the light emitting device 110 is disposed on the Ag sintered body film. Then, it may be formed by curing the Ag sintered film by applying a low temperature and/or pressure to the film. Accordingly, the light emitting device 110 may be bonded to the substrate 400 by the bonding layer 130 .

The bonding layer 130 formed from the metal sintered film has little change in volume or position even after the light emitting device 110 is disposed and then cured. Accordingly, it is possible to prevent an electric short from occurring due to the contact between the first bonding layer 131 and the second bonding layer 133 in the process of mounting the light emitting device 110 like a conventional paste. In addition, since the pre-fabricated sintered film is used, voids or pores do not occur in the bonding layer 130 during the mounting process of the light emitting device 110 , so that the heat dissipation efficiency of the bonding layer 130 can be prevented from being lowered. and it is possible to prevent a decrease in mechanical strength. Furthermore, since the thickness of the sintered film formed of the bonding layer 130 can be freely adjusted, the heat dissipation efficiency when the light emitting device 110 is driven can be improved by increasing the thickness of the sintered film. For example, the thickness of the bonding layer 130 may be about 10 to 30 μm. In addition, since curing the metal sintered film can be performed at a relatively low pressure and low temperature, the light emitting device 110 may be damaged by high temperature or high pressure in the process of contacting the light emitting device 110 to the substrate 400 . there is no

Meanwhile, the light emitting device 110 may further include a first pad electrode 113 and a second pad electrode 115 formed on a lower surface of the light emitting structure 111 , and the light emitting device 110 includes the pad electrodes 113 . , 115 , the relationship with the bonding layer 130 will be described in more detail with reference to FIGS. 2A and 2B .

The first pad electrode 113 and the second pad electrode 115 may be electrically connected to the n-type semiconductor layer and the p-type semiconductor layer (or vice versa), respectively. In particular, the first pad electrode 113 and the second pad electrode 115 may be formed to extend downwardly from the light emitting structure 111 . Accordingly, the first and second pad electrodes 113 and 115 are It may be located under the first light emitting device 110 . Alternatively, the first and second pad electrodes 113 and 115 may be positioned on the same plane as the lower surface of the light emitting structure 111 . Furthermore, the first and second pad electrodes 113 and 115 may be positioned higher than the lower surface of the light emitting structure 111 . In this case, grooves may be formed in the lower surface of the light emitting structure 111 , and the first and second pad electrodes 113 and 115 may be exposed in the grooves.

The first and second pad electrodes 113 and 115 may be electrically connected to the first electrode 421 and the second electrode 431 of the substrate 400 , respectively. In this case, the pad electrodes 113 and 115 may be electrically connected to the electrodes 421 and 431 by the bonding layer 130 .

Specifically, referring to FIG. 2A , the first and second pad electrodes 113 and 115 may contact the first bonding layer 131a and the second bonding layer 133a, respectively. The first bonding layer 131a may cover at least a portion of the first pad electrode 113 , and in particular, the first bonding layer 131a may cover a portion of a lower surface and a side surface of the first pad electrode 113 . . Similarly, the second bonding layer 133a may cover at least a portion of the second pad electrode 115 , and in particular, the second bonding layer 133a may partially cover a lower surface and a side surface of the second pad electrode 115 . can cover

More specifically, the first bonding layer 131a and the second bonding layer 133a are formed on side surfaces of the first and second pad electrodes 113 and 115 in which the first and second pad electrodes 113 and 115 face each other. All other sides can be covered except for . That is, as shown, one side of the first bonding layer 131a does not cover the side surfaces of the first pad electrode 113 that face the first and second pad electrodes 113 and 115, It may be formed parallel to the opposite side surface. The second bonding layer 133a may also be formed in parallel with the opposite side surfaces of the second pad electrode 113 without covering the side surfaces opposite to the first and second pad electrodes 113 and 115 among the side surfaces of the second pad electrode 113 . have. Furthermore, other side surfaces except for one side of the first bonding layer 131a may be formed parallel to the side surface of the light emitting device 110 , and other side surfaces except for one side of the second bonding layer 133a may be formed on the light emitting device ( 110) may be formed side by side.

Since the bonding layer 130a is not located in the spaced region between the first pad electrode 113 and the second pad electrode 115 , it is possible to prevent an electric short from occurring when the light emitting device 110 is mounted.

Also, as shown in FIG. 2B , the bonding layer 130b may be formed to cover lower surfaces and side surfaces of the first and second pad electrodes 113 and 115 . In this case, the horizontal cross-sectional area of the bonding layer 130b may be increased, so that heat dissipation efficiency when the light emitting device 10 is driven may be improved.

Referring back to FIG. 1 , the wavelength converter 120 may be positioned on the light emitting device 110 , and may cover at least a portion of an upper surface of the light emitting device 110 . Furthermore, the wavelength conversion unit 120 may be formed to have substantially the same area as the upper surface of the light emitting device 110 , and unlike the diagram, the area of the wavelength conversion unit 120 is the upper surface area of the light emitting device 110 , as shown. can be larger than

The wavelength converter 120 may have a sheet form, and the wavelength converter 120 in the sheet form may be adhered to the light emitting device 110 . The wavelength conversion unit 120 in the form of a sheet may be adhered by, for example, an adhesive.

The wavelength conversion unit 120 may include a phosphor and a supporting part for supporting the phosphor. The wavelength converter 120 may include various types of phosphors widely known to those skilled in the art, for example, garnet-type phosphors, aluminate phosphors, sulfide phosphors, oxynitride phosphors, nitride phosphors, fluoride-based phosphors, silicate phosphors, and the like. The wavelength of the light emitted from the light emitting device 110 may be converted to emit light of various colors. For example, when the light emitting device 110 emits light having a peak wavelength in the blue light band, the wavelength converter 120 may emit light having a longer peak wavelength than blue light (eg, green light, red light, or yellow light). light) emitting phosphor. Alternatively, when the light emitting device 110 emits light having a peak wavelength in the UV band, the wavelength conversion unit 120 includes light having a peak wavelength of a longer wavelength than UV light (eg, blue light, green light, red light, or a phosphor that emits yellow light). Accordingly, white light may be emitted from the light emitting device 10 . However, the present invention is not limited thereto, and in particular, in this embodiment, the wavelength converter 120 may include one type of phosphor.

The supporting part may include a polymer resin, a ceramic such as glass, and the like. The phosphors may be randomly disposed in the supporting part.

In addition, the wavelength converter 120 may include a single crystal material. The wavelength converter 120 including a single crystal material may be provided in the form of a phosphor sheet, and the wavelength converter 120 itself in the sheet form may be made of a single crystal phosphor, for example, the single crystal phosphor is a single crystal. YAG:Ce. Light passing through the wavelength conversion unit 120 including the single crystal phosphor sheet can emit light having a substantially constant color coordinate, so that the wavelength conversion unit 120 including the single crystal phosphor sheet is applied to a plurality of light emitting devices In this case, color coordinate deviation between the plurality of light emitting devices may be reduced.

The sidewall part 300 may cover the side surface of the light emitting part 100 , and specifically, the side surface of the light emitting device 110 , the side surface of the adhesive part 130 , and the side surface of the wavelength conversion part 120 . Furthermore, a portion of the sidewall portion 300 may further cover a portion of the lower surface of the light emitting device 110 . In this case, side surfaces of the pad electrodes 113 and 115 may be surrounded by the sidewall part 300 .

The sidewall part 300 may support the light emitting device 110 and may also protect the light emitting device 110 from an external environment. Furthermore, the sidewall part 300 may serve to reflect light. Since the sidewall part 300 is formed on the outer side of the light emitting device 10 , the light emitted from the light emitting part 100 may be concentrated upward. In particular, when the adhesive part 130 is formed to extend to the side surface of the light emitting device 110 and has an inclination, the sidewall part 300 of a portion in contact with the side surface of the adhesive part 130 may be inclined. Accordingly, the luminous efficiency of the light emitting device 10 may be further improved.

However, the present invention is not limited thereto, and the angle of light emitted from the light emitting unit 100 may be adjusted by adjusting the reflectivity and light transmittance of the sidewall part 300 as necessary.

The sidewall part 300 may include an insulating polymer material or ceramic, and further, may further include a filler capable of reflecting or scattering light. The sidewall part 300 may have light transmittance, light transmissivity, or light reflectivity. For example, the sidewall part 300 may include a silicone resin or a polymer resin such as an epoxy resin, a polyimide resin, or a urethane resin. In this embodiment, the sidewall part 300 may include a white silicone resin having light reflectivity.

The filler may be uniformly dispersed in the sidewall part 300 . The filler is not limited as long as it is a material capable of reflecting or scattering light, and may be, for example, titanium oxide (TiO ₂ ), silicon oxide (SiO ₂ ), or zirconium oxide (ZrO ₂ ). The sidewall part 300 may include at least one of the pillars. By adjusting the type or concentration of the filler, the reflectivity of the sidewall part 300 or the degree of light scattering may be adjusted.

Meanwhile, the upper surface of the sidewall part 300 and the upper surface of the light emitting part 100 may have the same height. That is, as shown, the upper surface of the sidewall part 300 and the upper surface of the wavelength converter 120 may be formed to be flush with each other.

3 is a cross-sectional view for explaining a light emitting device according to another embodiment of the present invention. The light emitting device 10b of FIG. 3 is different from the light emitting device of FIG. 1 in that it includes a plurality of light emitting units 100 .

The light emitting device 10b includes a plurality of light emitting units 100 positioned on a substrate 400 . In this case, the light emitting units 100 may be bonded to the substrate 400 by the bonding layer 130 .

The bonding layer 130 may include a metal sintered body. Accordingly, in the process of bonding the plurality of light emitting units 100 to the substrate 400 , the bonding layer 130 does not spread like a paste, and the shape and position can be almost maintained. Accordingly, the probability that one light emitting unit 100 is in electrical contact with another light emitting unit 100 adjacent thereto by the bonding layer 130 to cause an electrical short or a defect can be significantly reduced. Accordingly, the reliability of the manufactured light emitting device 10b can be improved. In addition, in the case of the light emitting device 10b including the plurality of light emitting units 100, high heat may be generated during driving. can be effectively released to the outside. Accordingly, it is possible to prevent the light emitting device 10b from being damaged by heat or from reducing the light emitting efficiency.

4 to 7 are a perspective view, a plan view, a bottom plan view, and a cross-sectional view for explaining a light emitting device according to another embodiment of the present invention. 8 is a plan view for explaining a light emitting device according to another embodiment of the present invention.

The light emitting device 10c described with reference to FIGS. 4 to 7 is different from the light emitting device 10 described with reference to FIG. 1 in that it includes a plurality of light emitting units 100 and 200 . Hereinafter, the light emitting device 10c will be described with a focus on differences, and a detailed description of the same configuration will be omitted.

4 to 7 , the light emitting device 10c may include at least two or more light emitting units, and specifically, the light emitting device 10c includes a first light emitting unit 100 , a second light emitting unit 200 , It includes a first bonding layer 130 , a second bonding layer 230 , a sidewall part 300 , and a substrate 400 . Furthermore, the light emitting device 10c may further include a protection element 310 .

The substrate 400 may be positioned at the bottom of the light emitting device 10c and may serve to support the first and second light emitting units 100 and 200 and the sidewall unit 300 . The substrate 400 may include a base 410 , and further, may further include first to fourth electrodes 421 , 431 , 423 , and 433 .

The first to fourth electrodes 421 , 431 , 423 , and 433 may be insulated from each other, penetrate vertically through the base 410 , and may be exposed on upper and lower portions of the base 410 . Accordingly, the electrodes 421 , 431 , 423 , and 433 may be electrically connected to the first and second light emitting units 100 and 200 positioned on the substrate 400 , and further, the lower portion of the substrate 400 . It may be electrically connected to an external power source through the exposed portion to supply power to the first and second light emitting units 100 and 200 .

However, the present invention is not limited thereto, and the first to fourth electrodes 421 , 431 , 423 , and 433 may have various shapes. For example, at least one of the first to fourth electrodes 421 , 431 , 423 , and 433 may be exposed through the side surface of the base 410 , and also, the first to fourth electrodes 421 , 431 , At least some of 423 and 433 may be electrically connected to each other. Also, depending on the number of light emitting units included in the light emitting device 10c, the light emitting device 10c may include five or more electrodes. The form of electrical connection between the light emitting units 100 and 200 and the electrodes will be described in detail later.

The first light emitting unit 100 and the second light emitting unit 200 may be positioned on the substrate 400 . The first light emitting unit 100 may include a first light emitting device 110 , a first wavelength conversion unit 120 , and a first adhesive unit 130 . The second light emitting unit 200 may include a second light emitting device 210 , a second wavelength conversion unit 220 , and a second adhesive unit 230 . The first light emitting unit 100 may emit light in a wavelength band different from that of the second light emitting unit 200 , for example, white light and amber color light, respectively.

In addition, the first light emitting unit 100 may include a light emitting structure 111 , a first pad electrode 113 , and a second pad electrode 115 , and the second light emitting unit 200 may include a light emitting structure 211 . , a third pad electrode 213 and a fourth pad electrode 215 may be included.

The first bonding layer 130 may be positioned between the first light emitting unit 100 and the substrate 400 to bond the first light emitting unit 100 to the substrate 400 . The second bonding layer 230 may be positioned between the second light emitting unit 200 and the substrate 400 to bond the second light emitting unit 200 to the substrate 400 . The first and second bonding layers 130 and 230 may include a metal sintered body in which metal particles are sintered, and in particular, an Ag sintered body in which Ag particles are sintered.

The first and second wavelength converters 120 and 220 may be positioned on the first and second light emitting devices 110 and 210, respectively, and may include a phosphor. In addition, the first and second wavelength conversion units 120 and 220 may further include a supporting unit supporting the phosphor. In particular, the first and second wavelength converters 120 and 220 may include single-crystal phosphor sheets, and the single-crystal phosphor sheets may be, for example, single-crystal YAG:Ce.

The first and second pad electrodes 113 and 115 may be electrically connected to the first electrode 421 and the second electrode 431 of the substrate 400 , respectively. Accordingly, power may be supplied to the first light emitting device 110 through the first and second electrodes 421 and 431 . Also, the third pad electrode 213 may be electrically connected to the third electrode 423 , and the fourth pad electrode 215 may be electrically connected to the fourth electrode 433 . Accordingly, power may be supplied to the second light emitting device 210 through the third and fourth electrodes 423 and 433 . In this case, the pad electrodes 113 , 115 , 213 , and 215 may be bonded and electrically connected to the electrodes 421 , 423 , 431 , and 433 by the bonding layers 130 and 230 .

Accordingly, the first light emitting device 110 and the second light emitting device 120 may be electrically connected to separate electrodes 421 , 431 , 423 , and 433 , respectively. By separately connecting power supplied to the electrodes 421 , 431 , 423 , and 433 , the first light emitting unit 100 and the second light emitting unit 200 may be independently driven. However, the present invention is not limited thereto, and the electrodes 421 , 431 , 423 , and 433 may be electrically interconnected with each other. Furthermore, the light emitting device 10c may further include a separate control unit (not shown), and the driving of the first light emitting unit 100 and the second light emitting unit 200 may be controlled by the control unit.

In some embodiments, the second wavelength converter 220 may not include a phosphor. For example, when the wavelength band of the light to be emitted from the second light emitting unit 200 substantially coincides with the wavelength band of the light emitted from the second light emitting device 210 , the second wavelength conversion unit 220 includes a phosphor You may not. In this case, the second wavelength converter 220 may include a light scattering agent such as _{TiO 2 .}

The sidewall part 300 may cover the side surfaces of the first and second light emitting devices 110 and 210 , and further cover the side surfaces of the first and second wavelength converters 120 and 220 . The sidewall part 300 may be in contact with the first and second light emitting parts 100 and 200 . In addition, a portion of the sidewall portion 300 may further cover a portion of lower surfaces of the first and second light emitting devices 110 and 210 , and in this case, the sidewalls of the pad electrodes 113 , 115 , 213 and 215 are sidewalls. It may be surrounded by the part 300 .

In addition, the thickness of the sidewall part 300 formed between the first light emitting part 100 and the second light emitting part 200 may be smaller than the thickness of the outer side edge of the sidewall part 300 . That is, as shown in FIG. 2 , the thickness x of the sidewall part 300 filling the spaced region between the first light emitting part 100 and the second light emitting part 200 is the second from the outer side of the sidewall part 300 . The thickness y corresponding to the shortest distance to one side of the first and second light emitting units 100 and 200 may be smaller than y. Accordingly, the distance between the first and second light emitting units 100 and 200 can be minimized to further miniaturize the light emitting device 10c, and further, the first and second light emitting units 100 and 200 can be removed from the outside. more effective protection.

In addition, the light emitting device 10c according to the present embodiments may further include a protection element 310 . The protection element 310 may be disposed in the sidewall part 300 , and may include, for example, a Zener diode. The protection element 310 is electrically connected to at least one of the first and second light emitting elements 110 and 120 to prevent the first and second light emitting elements 110 and 120 from being damaged due to electrostatic discharge. can The protection element 310 may be separately connected to each of the first and second light emitting elements 110 and 120 , or may be simultaneously connected to the first and second light emitting elements 110 and 120 .

According to the above-described embodiments, the light emitting devices 10 , 10a , and 10b include a first light emitting unit 100 and a second light emitting unit 200 spaced apart from each other on a substrate 400 , and the The first and second light emitting units 100 and 200 are electrically connected to different electrodes, respectively. Accordingly, the first light emitting unit 100 and the second light emitting unit 200 may be driven independently of each other, and a light emitting device 10a that selectively emits light of different colors may be provided as needed. Accordingly, it is possible to omit separately manufacturing at least two or more light emitting devices emitting light of different colors, thereby simplifying the manufacturing process. Furthermore, since only one light emitting device can emit light of a plurality of colors, it is possible to reduce the spatial ratio of the light emitting device in a specific application device.

Meanwhile, the light emitting device according to the present invention is not limited to the above-described embodiment, and may include three or more light emitting units. For example, as shown in FIG. 8 , the light emitting device 10d may include a plurality of first light emitting units 100 and a plurality of second light emitting units 200 . The plurality of first light emitting units 100 may be connected to each other in series or parallel, and the plurality of second light emitting units 200 may also be connected to each other in series or parallel. As described above, since the light emitting device 10d includes three or more light emitting units, the light emitting intensity of the light emitting device 10d may be improved.

In addition, the light emitting device of the present invention may include light emitting units that emit light of three or more colors.

The light emitting device described in the above embodiments may emit light of two or more colors from one light emitting device. Such a light emitting device may be applied to an application device requiring a plurality of light emitting colors, for example, a lamp for a vehicle. Hereinafter, a vehicle lamp including a light emitting device according to embodiments of the present invention will be described with reference to FIG. 9 .

9 is a front view for explaining a vehicle lamp according to another embodiment of the present invention.

Referring to FIG. 9 , the vehicle lamp 20 according to the present embodiment may include a combination lamp 23 , and further, may further include a main lamp 21 . The vehicle lamp 20 may be applied to various parts of a vehicle, such as a headlight, a backlight, or a side mirror light.

The main lamp 21 may be a main light emitting lamp in the vehicle lamp 20 , and for example, when the vehicle lamp 20 is used as a headlight, it may serve as a headlight illuminating the front of the vehicle.

The combination lamp 23 may include the light emitting device 10c according to embodiments of the present invention. The combination lamp 23 may function at least two or more. For example, when the vehicle lamp 20 is used as a headlight, the combination lamp 23 may function as a daytime running light (DRL) and a turn indicator lamp.

Specifically, in the vehicle including the vehicle lamp 20 of this embodiment, the light emitting device 10c of the combination lamp 23 emits white light from the first light emitting unit 100 during normal driving of the vehicle. emits Accordingly, the combination lamp 23 may function as a daytime running lamp by emitting white light. In addition, when turning on the turn signal lamp of the vehicle, the light emitting device 10c of the combination lamp 23 turns off the power of the first light emitting unit 100 and the second light emitting unit 200 ) emits amber-colored light. Accordingly, the combination lamp 23 may function as a direction indicator by emitting light of amber color. The operation of the combination lamp 23 and the light emitting device 10c may be controlled by a separate controller (not shown).

As such, the light emitting device 10c according to embodiments of the present invention may be used as a light source of the combination lamp 23 capable of performing at least two or more functions by emitting light of two or more colors. Since the light emitting device 10c according to embodiments of the present invention includes light emitting units emitting at least two or more different wavelengths of light, when manufacturing the vehicle lamp 20 including the combination lamp 23 , separate two The above-described process of mounting the light emitting device may be omitted. Accordingly, the defect rate of the vehicle lamp 20 can be reduced, and the manufacturing process can be simplified to improve the process yield. In addition, since the volume of the light emitting device 10c is relatively small, the space constraint during manufacture of the combination lamp 23 may be reduced, and various modifications and changes of the combination lamp 23 may be facilitated.

However, the present invention is not limited thereto, and the light emitting device may be applied to various other applications other than vehicle lamps. In addition, the present invention is not limited to the above-described various embodiments and features, and various modifications and changes are possible within the scope without departing from the spirit of the claims of the present invention.

Claims (18)

Board;
a light emitting unit positioned on the substrate and including a light emitting device and a wavelength conversion unit positioned on the light emitting device;
a bonding layer positioned between the light emitting unit and the substrate and bonding the light emitting unit to the substrate; and
Surrounding the side surface of the light emitting unit, comprising a side wall portion in contact with the side surface of the light emitting unit,
The bonding layer includes a metal sintered body including metal particles,
The light emitting device is positioned on its lower surface and includes a first pad electrode and a second pad electrode spaced apart from each other,
The first pad electrode and the second pad electrode each include side surfaces facing the first pad electrode and the second pad electrode,
The bonding layer includes a first bonding layer and a second bonding layer,
the first bonding layer covers side surfaces other than the lower surface of the first pad electrode and the opposite side surface of the first pad electrode;
the second bonding layer covers side surfaces other than the lower surface of the second pad electrode and the opposite side surface of the second pad electrode;
One side of the first bonding layer is positioned in parallel with the opposite side of the first pad electrode,
One side of the second bonding layer is positioned in parallel with the opposite side of the second pad electrode. The method according to claim 1,
The metal particles include Ag particles. delete delete delete The method according to claim 1,
The other side surfaces of the first bonding layer are parallel to the side surface of the light emitting device,
The other side surfaces of the second bonding layer are positioned in parallel with the side surface of the light emitting device. delete The method according to claim 1,
The bonding layer is a light emitting device having a thickness of 10 to 30㎛. The method according to claim 1,
The light emitting part and the bonding layer are each formed in plurality,
The plurality of light emitting units are bonded to the substrate by the plurality of bonding layers. Board;
a first light emitting unit positioned on the substrate and including a first light emitting device and a first wavelength conversion unit positioned on the light emitting device;
a second light emitting unit located on the substrate, spaced apart from the first light emitting unit, and including a second light emitting device and a second wavelength converting unit disposed on the light emitting device;
a bonding layer positioned between the first light emitting unit and the substrate and between the second light emitting unit and the substrate; and
Surrounding the side surfaces of the first and second light emitting units, including a side wall portion in contact with the side surfaces of the first and second light emitting units,
The first light emitting unit and the second light emitting unit emit light having different peak wavelengths,
The first and second bonding layers each include a metal sintered body including metal particles,
Each of the first light emitting device and the second light emitting device includes a first pad electrode and a second pad electrode that are positioned on a lower surface thereof and are spaced apart from each other,
The first pad electrode and the second pad electrode each include side surfaces facing the first pad electrode and the second pad electrode,
The bonding layer includes a first bonding layer and a second bonding layer,
the first bonding layer covers side surfaces other than the lower surface of the first pad electrode and the opposite side surface of the first pad electrode;
the second bonding layer covers side surfaces other than the lower surface of the second pad electrode and the opposite side surface of the second pad electrode;
One side of the first bonding layer is positioned parallel to the opposite side of the first pad electrode,
One side of the second bonding layer is positioned in parallel with the opposite side of the second pad electrode. 11. The method of claim 10,
The metal particles include Ag particles. 12. The method of claim 11,
The substrate includes first to fourth electrodes,
The first and second electrodes are electrically connected to the first light emitting unit, and the third and fourth electrodes are electrically connected to the second light emitting unit. 13. The method of claim 12,
The first to fourth electrodes are insulated from each other, and each of the first to fourth electrodes is exposed on an outer surface of the substrate. 11. The method of claim 10,
The first light emitting unit emits white light. 15. The method of claim 14,
The second light emitting unit is a light emitting device for emitting amber color light. delete delete 11. The method of claim 10,
The other side of the first bonding layer is parallel to the side of the first light emitting device,
The other side of the second bonding layer is parallel to the side of the second light emitting device.

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