KR102534589B1 - A light emitting device package - Google Patents

Abstract

The embodiment connects the package body, the first conductive layer and the second conductive layer disposed on the package body, the first conductive layer and the second conductive layer to each other, and the resin and the first conductive particles dispersed in the resin. It includes a protective layer comprising a, wherein the protective layer has insulating properties below a predetermined reference voltage, the protective layer has conductivity above the predetermined reference voltage.

Description

Light emitting device package {A LIGHT EMITTING DEVICE PACKAGE}

The embodiment relates to a light emitting device package.

Light emitting devices such as light emitting diodes or laser diodes (LD) using group 3-5 or group 2-6 compound semiconductor materials of semiconductors are developed in thin film growth technology and device materials to produce red, green, Various colors such as blue and ultraviolet can be realized, and white light with high efficiency can be realized by using fluorescent materials or combining colors. , safety, and environmental friendliness.

Transmission module of optical communication means, light emitting diode backlight replacing Cold Cathode Fluorescent Lamp (CCFL) constituting backlight of LCD (Liquid Crystal Display) display device, white light emitting diode lighting replacing fluorescent or incandescent bulb Applications are expanding to devices, automobile headlights and traffic lights.

Light emitting device packages are widely used in lighting devices and display devices. A light emitting device package may generally include a body, conductive layers positioned within the body, and a light emitting device (eg, LED) positioned on any one of the conductive layers.

The embodiment provides a light emitting device package capable of preventing damage caused by static electricity.

A light emitting device package according to an embodiment includes a package body; a first conductive layer and a second conductive layer disposed on the package body; and a protective layer connecting the first conductive layer and the second conductive layer to each other and including resin and first conductive particles dispersed in the resin, wherein the protective layer has insulating properties when the voltage is lower than a predetermined reference voltage. , the passivation layer has conductivity above the predetermined reference voltage.

The protective layer may further include second particles dispersed in the resin.

The first particles may include at least one of Al, Cu, Au, Zn, Ti, or Ag, or may be SiC.

Each of the first particles includes a metal particle and a coating layer covering a surface of the metal particle, and the coating layer may be formed of a metal having a lower oxidation property than the metal particle.

The protective layer may be disposed on one region of an upper surface of the package body positioned between the first conductive layer and the second conductive layer positioned under the light emitting device.

A width of the passivation layer connecting the first conductive layer and the second conductive layer may be 100 μm to 200 μm.

The protective layer may include: a first protective layer disposed on one region of an upper surface of the package body located between the first conductive layer and the second conductive layer located under the light emitting device; and a second protective layer disposed on one region of the first conductive layer, one region of the second conductive layer, and one region of the first protective layer positioned around the light emitting element.

A reflective layer disposed on the second passivation layer may be further included.

The protective layer may include one region of the first conductive layer, one region of the second conductive layer, and one region of the top surface of the package body between the first conductive layer and the second conductive layer located around the light emitting element. can be placed in an area.

The light emitting device package includes another area of the first conductive layer located around the light emitting device, another area of the second conductive layer, and an upper surface of the package body between the first conductive layer and the second conductive layer. A reflective layer disposed in another area of the may be further included.

A diameter of each of the second particles may be smaller than a diameter of each of the first particles. The second particles are SiC, SiO ₂ , Al ₂ O ₃ , or TiO ₂ may include at least one of them.

The package body includes a cavity including a side surface and a bottom, at least a portion of an upper surface of each of the first and second conductive layers is exposed by the cavity, and the protective layer is exposed by the cavity. It may be disposed at the bottom of the cavity positioned between the first and second conductive layers.

The content of the second particles is lower than the content of the first particles, and may be 10 [wt%] or more of the total weight of the protective layer.

The embodiment can prevent damage due to static electricity.

1 shows a plan view of a light emitting device package according to an embodiment.
FIG. 2 shows a cross-sectional view of the light emitting device package shown in FIG. 1 in an AB direction.
Figure 3a shows an embodiment of the protective layer shown in Figure 2.
Figure 3b shows another embodiment of the first particles shown in Figure 3a.
4 shows another embodiment of the protective layer shown in FIG. 2 .
5 shows a schematic diagram of conduction of the protective layer when a voltage higher than the reference voltage is applied.
6 is a plan view of a light emitting device package according to another embodiment.
FIG. 7 is a cross-sectional view of the light emitting device package shown in FIG. 6 in an AB direction.
8A is a plan view of a light emitting device package according to another embodiment.
FIG. 8B is a cross-sectional view of the light emitting device package shown in FIG. 8A in an AB direction.
9 is a cross-sectional view of a light emitting device package according to another embodiment.
10 shows an embodiment of the light emitting device shown in FIG. 1 .
11 illustrates a lighting device including a light emitting device package according to an embodiment.
12 illustrates a display device including a light emitting device package according to an embodiment.

Hereinafter, embodiments will be clearly revealed through the accompanying drawings and description of the embodiments. In the description of the embodiment, each layer (film), region, pattern or structure is “on” or “under” the substrate, each layer (film), region, pad or pattern. In the case where it is described as being formed in, "up / on" and "under / under" include both "directly" or "indirectly" formed through another layer. do. In addition, the criterion for the upper/upper or lower/lower of each layer will be described based on the drawings.

In the drawings, sizes are exaggerated, omitted, or schematically illustrated for convenience and clarity of explanation. Also, the size of each component does not fully reflect the actual size. Also, like reference numerals denote like elements throughout the description of the drawings.

1 shows a plan view of a light emitting device package 100 according to an embodiment, and FIG. 2 shows a cross-sectional view of the light emitting device package 100 shown in FIG. 1 in an AB direction.

1 and 2, the light emitting device package 100 includes a package body 110, a first conductive layer 122, a second conductive layer 124, a light emitting device 130, an adhesive member 135, and a protective layer 140 .

The package body 110 is insulating or thermally conductive, such as a silicon-based wafer level package, a silicon substrate, Al ₂ O ₃ , silicon carbide (SiC), Si ₃ N ₄ , aluminum nitride (AlN), and the like. It may be formed of a substrate having good conductivity, and may have a structure in which a plurality of substrates are stacked.

Alternatively, the package body 110 may be formed of a resin material such as polyphthalamide (PPA), EMC resin, or PCT resin, but is not limited thereto. In addition, the embodiment is not limited to the material, structure, and shape of the body described above.

In addition, for example, when the light emitting device 130 emits ultraviolet rays, the package body 110 is a material that is not discolored or damaged by ultraviolet rays, for example, high temperature co-fired ceramic (HTCC) or low temperature It may be made of co-fired ceramics (Low Temperature Cofired Ceramics: LTCC).

The first conductive layer 122 and the second conductive layer 124 may be spaced apart from each other on the surface of the package body 110 to be electrically separated from each other in consideration of heat dissipation or the arrangement of the light emitting device 130 .

The first conductive layer 122 and the second conductive layer 124 may be made of a conductive material such as titanium (Ti), copper (Cu), nickel (Ni), aluminum (Al), gold (Au), or chromium (Cr). , formed of at least one of tantalum (Ta), platinum (Pt), tin (Sn), silver (Ag), and phosphorus (P), or formed of an alloy (eg, Ti / Al) containing at least one of these It can be a single-layer or multi-layer structure. In another embodiment, the terms first conductive layer 122 and second conductive layer 124 may be used interchangeably with first lead frame and second lead frame.

A reflective member capable of reflecting light emitted from the light emitting device 130 may be coated on surfaces of the first and second conductive layers 122 and 124 . For example, the reflective member may be Ag, but is not limited thereto.

The light emitting element 130 is disposed on the first and second conductive layers 122 and 124 and is electrically connected to the first and second conductive layers.

FIG. 10 shows an embodiment of the light emitting device 130 shown in FIG. 1 .

Referring to FIG. 10 , the light emitting device 130 includes a substrate 310, a light emitting structure 320, a conductive layer 330, a first electrode 342, a second electrode 344, and a passivation layer, 350). For example, the light emitting device 130 may be a flip chip type light emitting diode.

The substrate 310 is a light-transmitting substrate, for example, any one of a sapphire substrate, a silicon (Si) substrate, a zinc oxide (ZnO) substrate, and a nitride semiconductor substrate, or GaN, InGaN, AlGaN, AlInGaN, SiC, GaP, InP, It may be a substrate in which at least one of Ga ₂ O ₃ and GaAs is laminated.

The light emitting structure 320 may include a plurality of compound semiconductor layers of Group 3 to 5 elements. For example, the light emitting structure 320 includes a first conductivity type semiconductor layer 322, a second conductivity type semiconductor layer 326, and between the first conductivity type semiconductor layer 322 and the second conductivity type semiconductor layer 326. It may include an active layer 324 located thereon.

A side surface of the light emitting structure 320 may be an inclined surface in an isolation etching process for dividing into unit chips. For example, the side of the light emitting structure 320 may be an inclined surface relative to the upper surface of the substrate 310 .

The first conductivity type semiconductor layer 322 is a compound semiconductor of a Group 3-5 element doped with a first conductivity type dopant, for example, In _x Al _y Ga _{1 -x- y} N (0≤x≤1, 0≤ y≤1, 0≤x+y≤1), and an n-type dopant such as Si, Ge, Sn, Se, or Te may be doped.

The active layer 324 emits light by energy generated during recombination of electrons and holes provided from the second conductivity type semiconductor layer 326 and the first conductivity type semiconductor layer 322. can create

The active layer 324 may have a composition formula of In _x Al _y Ga _{1 -x- y} N (0≤x≤1, 0≤y≤1, 0≤x+y≤1). The active layer 324 may include any one of a single quantum well structure, a multi quantum well (MQW) structure, a quantum dot structure, or a quantum wire structure.

When the active layer 324 has a multi-quantum well structure, the active layer 324 may be formed by stacking a plurality of well layers and a plurality of barrier layers. The energy band gap of the well layer is lower than that of the barrier layer.

The second conductivity type semiconductor layer 326 is a compound semiconductor of a Group 3-5 element doped with a second conductivity type dopant, for example, In _x Al _y Ga _{1 -x- y} N (0≤x≤1, 0≤ y≤1, 0≤x+y≤1), and a p-type dopant such as Mg, Zn, Ca, Sr, or Ba may be doped.

Between the active layer 324 and the first conductivity-type semiconductor layer 322 or between the active layer 324 and the second conductivity-type semiconductor layer 326 is a clad layer doped with an n-type or p-type dopant (not shown). ) may be formed, and the cladding layer may be a semiconductor layer including AlGaN or InAlGaN. The light emitting structure 320 may emit light of various wavelengths. For example, the light emitting structure 320 may generate ultraviolet rays (eg, UV-C), but is not limited thereto.

The conductive layer 330 may be disposed on the second conductive semiconductor layer 326 .

For example, the conductive layer 330 may be disposed between the second conductivity type semiconductor layer 326 and the second electrode 344 and may make ohmic contact with the second conductivity type semiconductor layer 330 . Since the conductive layer 330 reduces total reflection and has good light transmittance, it can increase the extraction efficiency of light emitted from the active layer 324 to the second conductivity type semiconductor layer 326. Although not shown in FIG. 10, light In order to improve extraction efficiency, irregularities may be formed on the surface of the second conductivity type semiconductor layer 326 or the conductive layer 330 .

The conductive layer 330 is a metal material that is in ohmic contact with the second conductive semiconductor layer 326, for example, Au, Pd, Pt, Ru, Re, Mg, Zn, Hf, Ta, Rh, Ir, W, Ti, It may include at least one of Ag, Cr, Mo, Nb, Al, Ni, Cu, W, Ti, V, or an alloy thereof.

Alternatively, the conductive layer 330 may be a transparent oxide-based material having high transmittance with respect to the emission wavelength, for example, indium tin oxide (ITO), tin oxide (TO), indium zinc oxide (IZO), indium zinc tin oxide (IZTO), or IAZO. (Indium Aluminum Zinc Oxide), IGZO (Indium Gallium Zinc Oxide), IGTO (Indium Gallium Tin Oxide), AZO (Aluminium Zinc Oxide), ATO (Aluminium Tin Oxide), GZO (Gallium Zinc Oxide), IrOx, RuOx, RuOx/ It may be implemented as a single layer or multilayer using one or more of ITO, Ni, Ag, Ni/IrOx/Au, or Ni/IrOx/Au/ITO. In other embodiments, the conductive layer 330 may be omitted.

The light emitting structure 320 may be etched to expose a region of the first conductive semiconductor layer 322 to dispose the first electrode 342 . For example, in the light emitting structure 320, a portion of the second conductivity type semiconductor layer 326, the active layer 324, and the first conductivity type semiconductor layer 322 is etched to form one region of the first conductivity type semiconductor layer 322. this can be exposed.

The first electrode 342 may be disposed on the exposed first conductivity type semiconductor layer 322 and may contact the exposed first conductivity type semiconductor layer 322 . In addition, the second electrode 344 may pass through a portion of the conductive layer 330 and contact the second conductive semiconductor layer 326, but is not limited thereto.

The second electrode 344 may be disposed on the upper surface of the conductive layer 330 and may contact the conductive layer 330 . The first electrode 342 and the second electrode 344 are conductive metals such as Au, Pd, Pt, Ru, Re, Mg, Zn, Hf, Ta, Rh, Ir, W, Ti, Ag, Cr, Mo , Nb, Al, Ni, Cu, WTi, V or at least one of alloys thereof.

The passivation layer 350 may be disposed on a side surface of the light emitting structure 320 .

For example, the passivation layer 350 may cover side surfaces of the light emitting structure 320 . In addition, the passivation layer 350 may be disposed on the remaining exposed area of the first conductivity type semiconductor layer 322 except for the area where the first electrode 342 is disposed. Also, the passivation layer 350 may be disposed on the remaining area of the upper surface of the conductive layer 330 except for the area where the second electrode 344 is disposed. In an embodiment in which the conductive layer 330 is omitted, the passivation layer 350 may be disposed on the second conductive semiconductor layer 326 .

The passivation layer 350 may expose at least a portion of the top surface of the first electrode 342 and at least a portion of the top surface of the second electrode 344 .

The passivation layer 350 may be formed of an insulating material such as SiO ₂ , SiO _x , SiO _x N _y , Si ₃ N ₄ , or Al ₂ O ₃ .

In addition, the passivation layer 350 may be a distributed Bragg reflective layer having a multilayer structure in which at least two layers having different refractive indices are alternately stacked at least once or more.

The adhesive member 135 is disposed between the upper surfaces of the first and second conductive layers 122 and 124 and the light emitting element 130, and the light emitting element 130 is attached to the first and second conductive layers 122 and 124. ) to bond. Also, the adhesive member 135 may electrically connect the first and second conductive layers 122 and 124 and the light emitting device 130 .

The adhesive member 135 may include a first adhesive member 135a and a second adhesive member 135b.

The first adhesive member 135a may be disposed between the first electrode 342 of the light emitting element 130 and the upper surface of the first conductive layer 122, and the first electrode 342 of the light emitting element 130 It may be bonded to the upper surface of the first conductive layer 122 . Also, the first adhesive member 135a may electrically connect the first electrode 342 of the light emitting device 130 and the first conductive layer 122 .

The second adhesive member 135b may be disposed between the second electrode 344 of the light emitting element 130 and the upper surface of the second conductive layer 124, and the second electrode 344 of the light emitting element 130 It may be bonded to the upper surface of the second conductive layer 124 . Also, the second adhesive member 135b may electrically connect the second electrode 344 of the light emitting element 130 and the second conductive layer 124 .

The first and second adhesive members 135a and 135b may be of a bump type and may be spaced apart from each other, and the light emitting device 130 may include the first and second conductive layers 122 and 124 can be flip chip bonded to

The light emitting device 130 of FIG. 2 is a flip chip type, but the embodiment is not limited thereto, and in other embodiments, the light emitting device 130 may be a horizontal type or a vertical type, die bonding or wire bonding ( It may be electrically connected to the first and second conductive layers 122 and 124 by wire bonding.

The protective layer 140 is disposed on the package body 110 and connects the first conductive layer 122 and the second conductive layer 124 to each other. For example, the protective layer 140 may be disposed on one region of the upper surface of the package body 110 positioned between the first conductive layer 122 and the second conductive layer 124 .

For example, the protective layer 140 may be disposed on one region of the upper surface of the package body 110 between the first conductive layer 122 and the second conductive layer 124 located under the light emitting element 130. .

The protective layer 140 may be black or white depending on the second particles 143 .

When the protective layer 140 is black, the protective layer 140 may absorb light emitted from the light emitting device 130, and thus light output or light extraction efficiency may decrease. By placing the protective layer 140 between the first conductive layer 122 and the second conductive layer 124 located below the light emitting device, light absorbed by the protective layer 140 can be reduced, thereby reducing light output. Alternatively, reduction in light extraction efficiency may be mitigated.

One end of the protective layer 140 may contact the first conductive layer 122 and the other end of the protective layer 140 may contact the second conductive layer 124 .

The protective layer 140 may be spaced apart from the light emitting element 130, but is not limited thereto, and in other embodiments, the protective layer 140 may contact the light emitting element 130.

The protective layer 140 serves to protect the light emitting device 130 from surge or static electricity. The term protective layer may be used interchangeably with an electrostatic protection layer or an electrostatic discharge suppression pattern layer.

FIG. 3A shows an embodiment 140a of the protective layer 140 shown in FIG. 2 .

Referring to FIG. 3A , the protective layer 140a may include a resin 141 and first particles 142 dispersed in the resin 141 .

The protective layer 140a contains the resin 141 in which the first particles 142 are dispersed on one region of the package body 110 positioned between the first conductive layer 122 and the second conductive layer 124. It may be formed by applying and curing the applied resin.

The protective layer 140a becomes an insulator having insulation properties below a predetermined reference voltage (eg, a threshold voltage or a potential barrier). The first particles 142 are spaced apart and evenly dispersed in the resin 141. Since the dispersed first particles 141 are electrically insulated below the reference voltage, the protective layer 140a may be an electrical insulator. .

On the other hand, above the reference voltage of the protective layer 140a, the first particles 141 dispersed by the tunneling effect conduct electricity to each other, so that the protective layer 140a becomes a conductor having conductivity.

For example, the operating voltage of the light emitting element 130 may be 3 [V] to 20 [V], and the reference voltage of the protective layer 140a may be 70 [V] to 200 [V], but is not limited thereto. no.

5 shows a schematic diagram of conduction of the passivation layer 140a when a voltage higher than the reference voltage is applied.

Referring to FIG. 5, when a voltage higher than the reference voltage is applied to the light emitting element 130 and the protective layer 140a due to surge or static electricity, a physically separated device is caused by a tunneling effect of a carrier. 1 The particles 141 may conduct electricity to each other, and conduction between the first conductive layer 122 and the first particles 142 and between the first particles 142 and the second conductive layer are also conducted to each other by the tunneling effect. A current path may be formed between the first conductive layer 122 and the second conductive layer 124 through the protective layer 140a.

The first particles 140a need to be spaced apart at predetermined intervals so that the protective layer 140a becomes an insulator when the voltage is less than the reference voltage and the protective layer 140a becomes a conductor when the voltage exceeds the reference voltage. The separation distance between the first particles 142 may be 3 μm to 6 μm. When the distance between the first particles 142 is less than 3 μm, the insulating property of the protective layer 140a is lowered below the reference voltage, and when the distance between the first particles 142 exceeds 6 μm, the reference voltage is reduced. Conductivity of the passivation layer 140a may decrease when the voltage is higher than the voltage.

For example, in order to simultaneously and stably secure the insulation of the protective layer 140a below the reference voltage and the conductivity of the protective layer 140a above the reference voltage, the spacing between the first particles 142 is 4 μm to 5 μm. can be

The resin 141 may be an acrylic resin, an epoxy resin, a urethane resin, a silicon resin, or the like, but is not limited thereto.

The first particles 142 may be conductive metal particles. For example, the first particles 142 may include at least one of Al, Cu, Au, Zn, Ti, or Ag. Alternatively, the first particles 142 may be metal carbide, for example SiC.

Figure 3b shows another embodiment 142 'of the first particles 142 shown in Figure 3a.

Referring to FIG. 3B , the first particles 142 ′ include metal particles (eg, the first particles 142 of FIG. 3A ) and a coating film 142a formed on a surface of the metal particles.

The coating layer 142a is to prevent oxidation of the first particles 142 and may be coated on the surfaces of the first particles 142 . When the first particles 142 are oxidized, the reference voltage of the protective layer 140a may change. Accordingly, the coating layer 142a may prevent the reference voltage of the protective layer 140a from changing due to oxidation of the first particles 142 .

The coating layer 142a may be a metal having a lower oxidation rate than the first particles 142 or a material having an insulating property. For example, the coating layer 142a may be Ag or Au.

For example, when the first particles 142 of FIG. 3A are Cu having a high oxidative property, the coating layer 142a may be made of Ag having a lower oxidative property than Cu.

When the first particles 142 are Al having low oxidation properties, the coating layer may be omitted.

The coating layer 142a may have a thickness of 0.1 μm to 3 μm. If the thickness of the coating film 142a is less than 0.1 μm, when the resin 141 is cured, the coating film 142a is oxidized and the first particles 142 cannot be prevented from being oxidized, and the thickness of the coating film 142a is 3 If it exceeds ㎛, a problem of cost increase may occur.

For example, the coating layer 142a may have a thickness of 0.5 μm to 1.5 μm in order to stably prevent oxidation of the first particles 142 during resin curing and to stably secure a tunneling effect.

For example, the weight ratio of the first particles 142 and the coating layer 142a may be 62:38, but is not limited thereto.

The protective layer 140 insulates the first conductive layer 122 and the second conductive layer 124 when the voltage is lower than the reference voltage to prevent a short circuit between them, thereby improving reliability. In addition, since the protective layer 140 functions as a conductor when static electricity equal to or higher than a reference voltage is applied, a current path is formed between the first conductive layer 122 and the second conductive layer 124 to pass through the light emitting element 130. The light emitting element 130 may be protected from static electricity by preventing the light emitting element 130 from being damaged by static electricity by bypassing the applied static electricity through the current path.

As the dispersibility of the first particles 142 and 142' increases, the function of the protective layer 140a as a conductor may be improved. In another embodiment, a dispersant or solvent may be further added to the resin 141 to improve the dispersibility of the first particles 142 .

FIG. 4 shows another embodiment 140b of the protective layer 140 shown in FIG. 2 . The same reference numerals as those in FIG. 3 denote the same configurations, and descriptions of the same configurations are simplified or omitted.

Referring to FIG. 4 , the protective layer 140b may include a resin 141 and first and second particles 142 and 143 dispersed in the resin 141 . The description of the first particles 142 shown in FIGS. 3A and 3B may be equally applied to the first particles 142 of FIG. 4 .

The second particles 143 may be dispersed in the resin 141 together with the first particles 142 to improve dispersibility of the first particles 142 .

The second particles 143 may be particles different from those of the first particles 142 and may have insulation or conductivity.

For example, the second particles 143 include at least one of SiC, SiO ₂ , Al ₂ O ₃ , or TiO ₂ , but are not limited thereto.

The second particles 143 may be positioned between the first particles 142 and may serve to inhibit contact of the first particles 142 with each other.

The separation distance between the first particles 142 and the second particles 143 may vary depending on the characteristics of the second particles.

For example, when the second particles 143 have insulating properties, the first particles 142 and the second particles 143 may contact each other.

On the other hand, when the second particles 143 have conductivity, the first particles 142 and the second particles 143 may be spaced apart from each other. For example, in this case, the description of the separation distance between the first particles 142 and the second particles 143 may be equally applied.

Electrical characteristics of the protective layer 140b may be adjusted according to the content of the first and second particles 142 and 143 . The content of the second particles 143 is lower than that of the first particles 142 and may be 10 [wt%] or more of the total weight of the protective layer 140b, but is not limited thereto.

When the second particles 143 are insulators, when the content of the second particles 143 increases, the content of the first particles 142 may be relatively low, so that the protective layer 140b has sufficient conductivity. It can be difficult. That is, the reference voltage of the protective layer 140b is higher than a desired range.

On the other hand, when the second particles 143 are conductors, when the content of the second particles 143 increases, the potential barrier for the tunneling effect is lowered, so that the reference voltage of the protective layer 140b is lower than a desired range.

In order to set the reference voltage of the protective layer 140b within a desired range, the mixing ratio of the first particles 142 and the second particles 143 may be 60:40 to 70:30.

In addition, the weight percentage of the first and second particles 142 and 143 may be 85 wt% to 90 wt% of the total weight of the protective layer 140b. For example, when the weight percentage of the first and second particles 142 and 143 is less than 85%, the reference voltage of the protective layer 140b is higher than a desired range, and the first and second particles 142 and 143 When the weight percentage exceeds 90%, the reference voltage of the protective layer 140b may be lower than a desired range.

In another embodiment, for example, the weight percentage of the first and second particles 142 and 143 may be 85 wt% to 87.5 wt% of the total weight of the protective layer 140b.

As the diameter of the first particles 142 decreases, the reference voltage of the protective layer 140b may decrease. This is because the distance between adjacent first particles decreases as the diameter of the first particles 142 decreases, so that a tunneling effect may occur between the first particles even at a low voltage.

On the other hand, as the diameter of the first particles 142 increases, the reference voltage of the protective layer 140b increases. This is because the distance between adjacent first particles increases as the diameter between the first particles 142 increases.

The diameter of each of the second particles 143 may be smaller than that of each of the first particles 142 .

The diameter of the first particles 142 may be 20 μm to 60 μm, and the diameter of the second particles 143 may be 1 μm to 4 μm.

When the diameter of the first particles 142 is less than 20 μm, the reference voltage of the protective layer 140b may be lower than the lower limit of the desired range, and when the diameter of the first particles 142 exceeds 60 μm, protection The reference voltage of the layer 140b may be higher than the upper limit of the desired range, which may cause damage to the light emitting device due to static electricity.

In another embodiment, in order to stably secure the range of the desired reference voltage (eg, 70 [V] to 200 [V] of the protective layer 140b, the diameter of the first particles 142 may be 35 μm to 45 μm. And, the diameter of the second particles 143 may be 2㎛ ~ 3㎛.

The width W1 of the protective layer 140b connecting the first conductive layer 122 and the second conductive layer 124 may be 100 μm to 200 μm. W1 may be equal to the separation distance between the first conductive layer 122 and the second conductive layer 124 .

When the width W1 of the protective layer 140b is less than 100 μm, the reference voltage of the protective layer 140b may be lower than the lower limit of the desired range. On the other hand, when the width W1 of the protective layer 140b exceeds 200 μm, the reference voltage of the protective layer 140b may be higher than the upper limit of the desired range, and as a result, damage to the light emitting device due to static electricity may occur. .

In order to stably secure the range of the desired reference voltage of the protective layer 140b (eg, 70 [V] to 200 [V], in another embodiment, the width W1 of the protective layer 140b is 140 μm to 160 μm. can

In addition, in order to stably protect the light emitting device 130, the width W1 of the protective layer 140b may be 100 μm to 150 μm.

In the embodiment, the protective layer 140b is formed by adjusting the content of the first particles, the content of the second particles, the diameter of the first particles, the diameter of the second particles, the distance between the first particles, and the distance between the second particles. By adjusting the reference voltage within a desired range, the first conductive layer 122 and the second conductive layer 124 may be insulated from each other below the reference voltage, and the light emitting element 130 may be protected from static electricity above the reference voltage. can do.

6 is a plan view of a light emitting device package 200 according to another embodiment, and FIG. 7 is a cross-sectional view of the light emitting device package 200 shown in FIG. 6 in an AB direction. The same reference numerals as those in FIGS. 1 and 2 denote the same configurations, and descriptions of the same configurations are simplified.

6 and 7, the light emitting device package 200 includes a package body 110, a first conductive layer 122, a second conductive layer 124, a light emitting device 130, an adhesive member 135, and a protective layer 240 and a reflective layer 250 .

The protective layer 240 is formed between one region of the upper surface of the package body 110 and one region of the upper surface of the first conductive layer 122 positioned between the first conductive layer 122 and the second conductive layer 124 . , and disposed on one region of the upper surface of the second conductive layer 14.

The protective layer 240 may contact the first conductive layer 122 and the second conductive layer 124 and connect the first conductive layer 122 and the second conductive layer 124 to each other.

The composition, content, reference voltage, and function of the protective layer 140 described in FIGS. 1 to 5 and the size and content of the first and second particles 142 and 143 may be equally applied to the protective layer 240 .

For example, the protective layer 240 includes a first protective layer 242 positioned between the first conductive layer 122 and the second conductive layer 124, and a first conductive layer positioned around the light emitting element 130 ( 122 , one region of the second conductive layer 124 , and one region of the first protective layer 240 .

For example, the second passivation layer 140 may include the remaining area of the first conductive layer 122 excluding the area where the light emitting element 130 is disposed, the remaining area of the second conductive layer 124, and the first passivation layer 240. ) can be placed on the remaining area of .

The reflective layer 250 is disposed on the protective layer 240 . For example, the reflective layer 250 may be disposed on the upper surface of the second protective layer 244 .

The reflective layer 250 may be formed of a reflective material capable of reflecting light emitted from the light emitting device 130, for example, a reflective metal such as Al or Ag or a resin having high reflectivity.

Since the protective layer 240 is an insulator below the reference voltage, the light emitting element 130 can be prevented from being shorted by the protective layer 240 even if the reflective layer is made of a conductive metal. In addition, since the reflective layer 250 blocks light irradiated from the light emitting device 130 from being absorbed by the protective layer 240, the light output or light extraction efficiency of the embodiment can be prevented from being reduced.

8A is a plan view of a light emitting device package 300 according to another embodiment, and FIG. 8B is a cross-sectional view of the light emitting device package 300 shown in FIG. 8A in an AB direction. The same reference numerals as those in FIGS. 1 and 2 denote the same configurations, and descriptions of the same configurations are simplified or omitted.

8A and 8B, the light emitting device package 300 includes a package body 110, a first conductive layer 122, a second conductive layer 124, a light emitting device 130, an adhesive member 135, and a protective layer 340, and a reflective layer 350.

The protective layer 340 includes one region of the first conductive layer 122 located around the light emitting element 130, one region of the second conductive layer 124 located around the light emitting element 130, and the light emitting element ( 130 may be disposed on one region of the upper surface of the package body 110 between the first conductive layer 122 and the second conductive layer 124 located around the periphery. The protective layer 240 may contact one region of the first conductive layer 122 and one region of the second conductive layer 124 located around the light emitting element 130, and One region and one region of the second conductive layer 124 may be connected to each other.

The composition, content, reference voltage and function of the protective layer 140 described in FIGS. 1 to 5 and the size and content of the first and second particles 142 and 143 may be equally applied to the protective layer 340 .

The reflective layer 350 includes another region of the first conductive layer 122 located around the light emitting element 130, another region of the second conductive layer 124 located around the light emitting element 130, and the other region of the light emitting element 130. ) may be disposed in another area of the upper surface of the package body 110 between the first conductive layer 122 and the second conductive layer 124 positioned around the .

The protective layer 340 may be disposed closer to the light emitting device 130 than the reflective layer 350 and may contact the reflective layer 350 . For example, the protective layer 340 may be positioned adjacent to the light emitting device 130 , and the reflective layer 350 may be positioned outside or around the protective layer 340 . In another embodiment, the reflective layer may be disposed closer to the light emitting device than the protective layer. For example, a protective layer may be located outside or around the reflective layer.

The reflective layer 350 blocks light irradiated from the light emitting device 130 from being absorbed by the protective layer 340, thereby preventing light output or light extraction efficiency from being reduced.

9 shows a cross-sectional view of a light emitting device package 400 according to another embodiment.

Referring to FIG. 9 , the light emitting device package 400 includes a package body 410, a first conductive layer 412, a second conductive layer 414, a light emitting device 420, a wire 430, and a protective layer 440. ), and a resin layer 470.

The package body 410 may have a cavity 403 composed of a side surface 401 and a bottom 402, and the side surface 401 of the cavity 403 is based on the bottom 402 of the cavity 403. can be inclined Description of the material of the package body 110 of FIGS. 1 and 2 may be equally applied to the package body 410 .

The first conductive layer 412 and the second conductive layer 414 may be spaced apart from each other and disposed on the package body 410 . At least a portion of an upper surface of each of the first and second conductive layers 412 and 414 may be exposed through the cavity 403 of the package body 410 .

Also, each of the first and second conductive layers 412 and 414 may pass through the package body 110 and be exposed to the outside of the package body 410 . For example, one end of each of the first and second conductive layers 412 and 414 may be exposed to the side of the package body 410 .

The light emitting element 420 may be disposed on the upper surface of the first conductive layer 412 exposed by the cavity 403, and the first conductive layer 412 and the second conductive layer ( 414) can be electrically connected. For example, the light emitting device 420 may be a vertical type, a horizontal type, or a flip chip type.

The protective layer 440 may be disposed on the bottom of the cavity 403 positioned between the first conductive layer 412 and the second conductive layer 414 exposed by the cavity 403 . The protective layer 440 may contact the first conductive layer 412 and the second conductive layer 414 and connect the first conductive layer 412 and the second conductive layer 414 to each other.

The protective layer 440 functions as an insulator that insulates between the first conductive layer 412 and the second conductive layer 414 when the voltage is lower than the reference voltage, and protects the light emitting element 420 from static electricity when the voltage is higher than the reference voltage. .

The composition, content, reference voltage, and function of the protective layer 140 described in FIGS. 1 to 5, and the size and content of the first and second particles 142 and 143 are the same as those of the protective layer 440 shown in FIG. can be applied

Although not shown in FIG. 9 , in another embodiment, a reflective layer (not shown) disposed on the protective layer 440 may be further included. By blocking what is absorbed by the light, it can be prevented from reducing light output or light extraction efficiency.

The light emitting device package 400 may further include a reflective layer 450 and an insulating layer 460 .

The reflective layer 450 may be disposed on the side surface 401 of the cavity 403 of the package body 410 and reflect light emitted from the light emitting device 420 to improve light extraction efficiency. The reflective layer 450 may be a reflective metal such as Al or Ag.

The insulating layer 460 may be disposed between the reflective layer 450 and the first conductive layer 412 and between the reflective layer 450 and the second conductive layer 414, and may be disposed between the reflective layer 450 and the first and second conductive layers. It electrically insulates between the conductive layers.

The resin layer 470 is filled in the cavity 403 of the package body 410 to surround the light emitting element 420 and protects the light emitting element 420 and the wire 430 from the external environment. The resin layer 470 may be made of a colorless and transparent polymer resin material such as epoxy or silicone. The resin layer 470 may contain a phosphor to change the wavelength of light emitted from the light emitting element 420 .

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

Another embodiment may be implemented as a display device, an indicating device, and a lighting system including the light emitting device or light emitting device package described in the above-described embodiments. For example, the lighting system may include a lamp, a vehicle lamp, and a street light. can

11 illustrates a lighting device including a light emitting device package according to an embodiment.

Referring to FIG. 11 , the lighting device may include a cover 1100, a light source module 1200, a radiator 1400, a power supply 1600, an inner case 1700, and a socket 1800. Also, the lighting device according to the embodiment may further include any one or more of the member 1300 and the holder 1500 .

The cover 1100 may have a bulb or hemisphere shape, may be hollow, and may have a shape in which one portion is open. The cover 1100 may be optically coupled to the light source module 1200 . For example, the cover 1100 may diffuse, scatter, or excite light provided from the light source module 1200 . The cover 1100 may be a kind of optical member.

The cover 1100 may be combined with the heat dissipation body 1400 . The cover 1100 may have a coupling part coupled to the heat dissipation body 1400 .

The inner surface of the cover 1100 may be coated with milky white paint. The milky white paint may include a diffusion material that diffuses light. The surface roughness of the inner surface of the cover 1100 may be greater than that of the outer surface of the cover 1100 . This is to sufficiently scatter and diffuse the light from the light source module 1200 and emit it to the outside.

The material of the cover 1100 may be glass, plastic, polypropylene (PP), polyethylene (PE), or polycarbonate (PC). Here, polycarbonate is excellent in light resistance, heat resistance, and strength. The cover 1100 may be transparent so that the light source module 1200 can be seen from the outside, but is not limited thereto and may be opaque. The cover 1100 may be formed through blow molding.

The light source module 1200 may be disposed on one surface of the heat sink 1400, and heat generated from the light source module 1200 may be conducted to the heat sink 1400. The light source module 1200 may include a light source unit 1210 , a connection plate 1230 , and a connector 1250 . The light source unit 1210 may include any one of the light emitting device packages according to the embodiment.

The member 1300 may be disposed on an upper surface of the heat dissipating body 1400 and has a plurality of light source units 1210 and a guide groove 1310 into which the connector 1250 is inserted. The guide groove 1310 may correspond to or be aligned with the board of the light source unit 1210 and the connector 1250 .

The surface of the member 1300 may be applied or coated with a light reflecting material.

For example, the surface of the member 1300 may be coated or coated with a white paint. The member 1300 may reflect light reflected on the inner surface of the cover 1100 and returned toward the light source module 1200 toward the cover 1100 again. Accordingly, light efficiency of the lighting device according to the embodiment may be improved.

The member 1300 may be made of an insulating material, for example. The connection plate 1230 of the light source module 1200 may include an electrically conductive material. Thus, electrical contact may be made between the radiator 1400 and the connection plate 1230 . The member 1300 may be made of an insulating material to block an electrical short between the connection plate 1230 and the radiator 1400 . The radiator 1400 may receive heat from the light source module 1200 and heat from the power supply 1600 and dissipate heat.

The holder 1500 blocks the receiving groove 1719 of the insulating part 1710 of the inner case 1700 . Accordingly, the power supply unit 1600 accommodated in the insulation unit 1710 of the inner case 1700 may be sealed. The holder 1500 may have a guide protrusion 1510 , and the guide protrusion 1510 may have a hole through which the protrusion 1610 of the power supply unit 1600 passes.

The power supply unit 1600 processes or converts an electrical signal received from the outside and provides it to the light source module 1200 . The power supply unit 1600 may be accommodated in the receiving groove 1719 of the inner case 1700, and may be sealed inside the inner case 1700 by the holder 1500. The power supply unit 1600 may include a protrusion 1610, a guide unit 1630, a base 1650, and an extension unit 1670.

The guide part 1630 may have a shape protruding outward from one side of the base 1650 . The guide part 1630 may be inserted into the holder 1500 . A plurality of components may be disposed on one surface of the base 1650 . A number of parts include, for example, a DC converter for converting AC power provided from an external power source into DC power, a driving chip for controlling driving of the light source module 1200, and an ESD (ElectroStatic ESD) for protecting the light source module 1200. discharge) protection device and the like, but is not limited thereto.

The extension 1670 may have a shape protruding outward from the other side of the base 1650 . The extension part 1670 may be inserted into the connection part 1750 of the inner case 1700 and receive an electrical signal from the outside. For example, the width of the extension part 1670 may be equal to or smaller than that of the connection part 1750 of the inner case 1700 . Each end of the "+ wire" and the "- wire" may be electrically connected to the extension 1670, and the other ends of the "+ wire" and the "- wire" may be electrically connected to the socket 1800. .

The inner case 1700 may include a molding part together with the power supply part 1600 therein. The molding part is a part where the molding liquid is hardened, and allows the power supply part 1600 to be fixed inside the inner case 1700.

12 illustrates a display device including a light emitting device package according to an embodiment.

Referring to FIG. 12 , the display device 800 includes a bottom cover 810, a reflector 820 disposed on the bottom cover 810, light emitting modules 830 and 835 emitting light, and a reflector 820. An optical sheet including a light guide plate 840 disposed in front of the light emitting modules 830 and 835 and guiding light emitted from the light emitting modules 830 and 835 toward the front of the display device, and prism sheets 850 and 860 disposed in front of the light guide plate 840, A display panel 870 disposed in front of the optical sheet, an image signal output circuit 872 connected to the display panel 870 and supplying image signals to the display panel 870, and disposed in front of the display panel 870 A color filter 880 may be included. Here, the bottom cover 810, the reflector 820, the light emitting modules 830 and 835, the light guide plate 840, and the optical sheet may form a backlight unit.

The light emitting module may include light emitting device packages 835 mounted on a substrate 830 . Here, a PCB or the like may be used as the substrate 830 . The light emitting device package 835 may be any one of the above-described embodiments.

The bottom cover 810 may accommodate components within the display device 800 . In addition, the reflector 820 may be provided as a separate component as shown in this drawing, or may be provided in a form coated with a highly reflective material on the rear surface of the light guide plate 840 or the front surface of the bottom cover 810. .

Here, the reflector 820 may use a material that has a high reflectance and can be used as an ultra-thin type, and may use polyethylene terephthalate (PET).

In addition, the light guide plate 830 may be formed of polymethylmethacrylate (PMMA), polycarbonate (PC), or polyethylene (PE).

The first prism sheet 850 may be formed of a light-transmitting and elastic polymer material on one surface of the support film, and the polymer may have a prism layer in which a plurality of three-dimensional structures are repeatedly formed. Here, the plurality of patterns may be provided in a stripe type with repeated crests and valleys as shown.

In the second prism sheet 860 , directions of peaks and valleys of one surface of the support film may be perpendicular to directions of peaks and valleys of one surface of the support film in the first prism sheet 850 . This is to evenly distribute the light transmitted from the light emitting module and the reflective sheet to the entire surface of the display panel 1870 .

Also, although not shown, a diffusion sheet may be disposed between the light guide plate 840 and the first prism sheet 850 . The diffusion sheet may be made of polyester and polycarbonate-based materials, and may maximize a light projection angle through refraction and scattering of light incident from the backlight unit. Further, the diffusion sheet includes a support layer including a light diffusing agent, and a first layer and a second layer formed on the light exit surface (direction of the first prism sheet) and the light incident surface (direction of the reflective sheet) and not containing the light diffuser. can include

In an embodiment, the diffusion sheet, the first prism sheet 850, and the second prism sheet 860 form an optical sheet, and the optical sheet is made of another combination, for example, a micro lens array or a diffusion sheet and a micro lens array. It may be made of a combination of or a combination of one prism sheet and a micro lens array.

A liquid crystal display may be disposed on the display panel 870, and other types of display devices requiring a light source may be provided in addition to the liquid crystal display panel 860.

Features, structures, effects, etc. described in the embodiments above are included in at least one embodiment of the present invention, and are not necessarily limited to only one embodiment. Furthermore, the features, structures, effects, etc. illustrated in each embodiment can be combined or modified with respect to other embodiments by a person having ordinary knowledge in the field to which the embodiments belong. Therefore, contents related to these combinations and variations should be construed as being included in the scope of the present invention.

110: package body 122: first conductive layer
124: second conductive layer 130: light emitting element
135: adhesive member 140: protective layer
141: resin 142: first particle
143: second particle.

Claims (14)

package body;
a first conductive layer and a second conductive layer disposed on the package body; and
A protective layer connecting the first conductive layer and the second conductive layer to each other;
The protective layer includes a resin and conductive first particles dispersed in the resin,
Each of the first particles includes a metal particle and a coating film covering a surface of the metal particle, wherein the coating film is made of a metal having a lower oxidation property than the metal particle. According to claim 1,
The protective layer,
A light emitting device package further comprising second particles dispersed in the resin together with the first particles. According to claim 2,
The metal particles of the first particles include at least one of Al, Cu, Au, Zn, Ti or Ag,
The second particles are SiC, SiO ₂ , Al ₂ O ₃ , or TiO ₂ Light emitting device package containing at least one of. According to claim 1,
Below a predetermined reference voltage, the protective layer has insulation, and above the predetermined reference voltage, the protective layer has conductivity. According to claim 2,
The diameter of each of the second particles is smaller than the diameter of each of the first particles,
The content of the second particles is lower than the content of the first particles, 10 [wt%] or more of the total weight of the protective layer light emitting device package.
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