KR20150099070A - Lighting device packge - Google Patents

Abstract

An embodiment of the present invention relates to a lighting device package. The lighting device package includes: a substrate; first and second electrodes arranged on the substrate; a light emitting device which is arranged on one part of the first electrode; a ceramic layer which is arranged on one part of the second electrode; a wire which has one end connected to the light emitting device and the other end connected to the other part of the second electrode, on which the ceramic layer is not arranged; and a reflection member which is arranged on the other part of the second electrode. The reflection member covers one end of the wire. The upper surface of the reflection member is arranged on the same plane as the upper surface of the ceramic layer.

Description

[0001] LIGHTING DEVICE PACKAGE [0002]

An embodiment relates to a light emitting device package.

The light emitting device package generally includes a substrate and a light emitting element mounted on the substrate.

As a light emitting device used in a light emitting device package, a light emitting diode (LED) is a kind of semiconductor device that converts electrical energy into light.

The light emitting diode has advantages of low power consumption, semi-permanent lifetime, fast response speed, safety, and environmental friendliness compared with conventional light sources such as fluorescent lamps and incandescent lamps. Therefore, much research has been conducted to replace conventional light sources with light emitting diodes. Light emitting diodes are increasingly used as light sources for various lamps used in indoor / outdoor, liquid crystal display devices, electric sign boards, streetlights, and the like .

In a conventional ceramic substrate used in a light emitting device package, copper, silver, and tungsten or a conductive material equivalent thereto is used on one surface of the light emitting device to effectively dissipate heat generated from the light emitting device have. In order to prevent the change of the conductive material due to oxidation and sulfuration, the conductive material is plated with gold or silver to perform surface protection. However, the surface protection of the conductive material by the gold plating has a problem that the reflectance of light from the light emitting element is low and the light absorption efficiency is high, so that the light emitting efficiency is lowered and the cost of the entire light emitting device package is increased due to the gold.

Embodiments provide a light emitting device package capable of improving light emitting efficiency.

Further, the embodiment provides a light emitting device package capable of reducing manufacturing cost.

A light emitting device package according to an embodiment includes: a substrate; First and second electrodes disposed on the substrate; A light emitting element disposed on a portion of the first electrode; A ceramic layer disposed on a portion of the second electrode; One end connected to the light emitting element and the other end connected to another portion of the second electrode on which the ceramic layer is not disposed; And a reflective member disposed on another portion of the second electrode, wherein the reflective member embeds one end of the wire, and the upper surface of the reflective member is disposed coplanar with the upper surface of the ceramic layer do.

Use of the light emitting device package according to the embodiment has an advantage that the light emitting efficiency can be improved.

Further, there is an advantage that the manufacturing cost can be reduced.

1 is a sectional view of a light emitting device package according to an embodiment;
Fig. 2 is an exploded cross-sectional view of a part of the light emitting device package shown in Fig. 1; Fig.
3 is a sectional view of a modified example of the light emitting device package shown in FIG.
FIGS. 4 to 7 are views for explaining a first method of manufacturing the light emitting device package shown in FIG. 1. FIG.
8 is a view for explaining a method of manufacturing the light emitting device package shown in FIG.
FIGS. 9 to 13 are views for explaining a second method of manufacturing the light emitting device package shown in FIG. 1. FIG.
FIG. 14 is a view for explaining a method of manufacturing the light emitting device package shown in FIG. 3; FIG.

The thickness and size of each layer in the drawings are exaggerated, omitted, or schematically shown for convenience and clarity of explanation. Also, the size of each component does not entirely reflect the actual size.

In the description of the embodiments according to the present invention, in the case where an element is described as being formed on "on or under" another element, the upper (upper) or lower (lower) (On or under) all include that the two elements are in direct contact with each other or that one or more other elements are indirectly formed between the two elements. Also, when expressed as "on or under", it may include not only an upward direction but also a downward direction with respect to one element.

Hereinafter, a light emitting device package according to an embodiment of the present invention will be described with reference to the accompanying drawings.

FIG. 1 is a cross-sectional view of a light emitting device package according to an embodiment, and FIG. 2 is an exploded cross-sectional view explaining parts of the light emitting device package shown in FIG.

1 and 2, a light emitting device package according to an embodiment may include a substrate 100, first and second electrodes 300a and 300b, a light emitting device 500, and a ceramic layer 700 have.

The substrate 100 may be a printed circuit pattern on an insulator. For example, the substrate 100 may be a printed circuit board (PCB), a metal core PCB, a flexible PCB, a ceramic PCB . ≪ / RTI > The substrate 100 may also be a substrate comprising epoxy and glass fibers. Here, the epoxy may include FR-4 or CEM-3.

The first and second electrodes 300a and 300b may be disposed on the substrate 100.

Each of the first electrode 300a and the second electrode 300b may be electrically connected to the light emitting device 500. For example, the first electrode 300a may be electrically connected to the (+) electrode of the light emitting device 500, and the second electrode 300b may be electrically connected to the (-) electrode of the light emitting device 500.

The first electrode 300a and the second electrode 300b may be disposed on the substrate 100. The first electrode 300a and the second electrode 300b disposed on the substrate 100 may be spaced apart from each other by a predetermined distance.

The light emitting device 500 may be disposed on the first electrode 300a. Specifically, the light emitting device 500 may be disposed on a portion of the upper surface of the first electrode 300a.

When the light emitting device 500 is disposed on the first electrode 300a, the first electrode 300a and the light emitting device 500 can be electrically connected without a separate wire w. When the light emitting device 500 is disposed on the first electrode 300a, the light emitting device 500 may be electrically connected to the second electrode 300b through the wire w.

The ceramic layer 700 may be disposed on the first electrode 300a. Specifically, a ceramic layer 700 having a predetermined thickness may be disposed on a portion of the first electrode 300a on which the light emitting device 500 is not disposed.

A ceramic layer 700 may be disposed on the second electrode 300b. Specifically, the ceramic layer 700 may be disposed on a portion of the upper surface of the second electrode 300b. Here, the portion where the ceramic layer 700 is not disposed on the upper surface of the second electrode 300b may be a portion to which the wire w is connected.

The light emitting element 500 is disposed on the first electrode 300a. Specifically, the light emitting device 500 may be disposed on the upper surface of the first electrode 300a.

The light emitting devices 500 may be disposed on the first electrode 300a or one or more.

The light emitting device 500 may be a light emitting diode chip that emits red, green, or blue light, or a light emitting diode chip that emits ultraviolet light. Here, the light emitting diode may be a lateral type, a vertical type, or a flip chip type, and may be a blue, a red, a yellow, or a green. It can diverge.

The light emitting device 500 may include a light emitting structure including a first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer. For example, the light emitting structure may include an active layer disposed between the first conductive semiconductor layer and the second conductive semiconductor layer.

The first conductive semiconductor layer may include an n-type semiconductor layer and may be selected from among GaN, AlN, AlGaN, InGaN, InN, InAlGaN, AlInN, AlGaAs, GaP, GaAs, GaAsP, AlGaInP, An n-type dopant such as Se or Te can be doped.

In the active layer, electrons (or holes) injected through the first conductive type semiconductor layer and holes (or electrons) injected through the second conductive type semiconductor layer meet with each other to form an energy band corresponding to the formation material of the active layer, Is a layer which emits light due to a difference in band gap of the light emitting layer. The active layer may be formed of any one of a single well structure, a multi-well structure, a quantum dot structure, or a quantum wire structure, but is not limited thereto.

The second conductivity type semiconductor layer may be a p-type semiconductor layer and may be selected from GaN, AlN, AlGaN, InGaN, InN, InAlGaN, AlInN, AlGaAs, GaP, GaAs, GaAsP, AlGaInP, A p-type dopant such as Sr, Ba or the like may be doped.

Meanwhile, the first conductivity type semiconductor layer may include a p-type semiconductor layer and the second conductivity type semiconductor layer may include an n-type semiconductor layer. Further, a semiconductor layer including an n-type or p-type semiconductor layer may be further formed under the second conductive type semiconductor layer. Accordingly, the light emitting structure may include at least one of an n-p junction structure, a p-n junction structure, an n-p-n junction structure, and a p-n-p junction structure.

The light emitting device 500 can selectively emit light in the range of the visible light band to the ultraviolet light band, and emit light having a color inherent to the semiconductor material.

The ceramic layer 700 may be disposed on the first and second electrodes 300a and 300b. Specifically, the ceramic layer 700 may be disposed on a portion of the upper surface of the first electrode 300a on which the light emitting device 500 is not disposed, and may be disposed on a portion of the upper surface of the second electrode 300b. have.

In addition, the ceramic layer 700 may be disposed on the substrate 100. Specifically, a portion where the first electrode 300a and the second electrode 300b are not disposed on the substrate 100, in particular, between the first electrode 300a and the second electrode 300b on the substrate 100 .

The ceramic layer 700 may be disposed on the surfaces of the first and second electrodes 300a and 300b to protect the surfaces of the first and second electrodes 300a and 300b from external factors such as moisture and air.

In the embodiment of the present invention, instead of the gold plating layer, a ceramic layer 700 is formed on the surfaces of the first and second electrodes 300a and 300b, . Therefore, since a ceramics which is cheaper than gold is used, the manufacturing cost of the entire light emitting device package can be reduced.

In addition, since the ceramic layer 700 has a lower light absorptivity than the conventional gold plating layer, the luminous efficiency of the entire light emitting device package can be improved.

In addition, the ceramic layer 700 has a migration problem (a phenomenon in which silver (Ag) precipitates when a voltage is applied in the presence of moisture) and a yellowing problem (silver (Ag) (Silver sulfide silver (AgS)) due to the reaction with silver (silver).

The thickness of the ceramic layer 700 is thinner than the thickness of the light emitting device 500. Specifically, the thickness of the ceramic layer 700 may be greater than 0 and less than or equal to 0.1 mm. Since the ceramic layer 700 having such a thickness can be disposed at a position lower than the uppermost surface of the light emitting device 500, the light emitted from the light emitting device 500 is diffused in the molding member 900, 700 can be reduced and the light emitted from the light emitting device 500 and the light reflected inside the molding member 900 can be reflected to the outside to improve the overall luminous efficiency of the light emitting device package, The amount of plating that protects the surfaces of the second electrodes 300a and 300b can be reduced, thereby reducing manufacturing costs. When the thickness of the ceramic layer 700 is more than 0.1 mm, the light path from the light emitting device 500 can be blocked and the light efficiency may be lowered.

The ceramic layer 700 may be a layer formed by processing and molding a base metal or an inorganic material at a predetermined temperature, and may be Alumian and Low Temperature co-fired ceramic (LTCC). Since the alumina and LTCC have a light reflectance of 90% or more, light from the light emitting element 500 can be easily reflected to the outside.

The light emitting device package according to the embodiment shown in FIGS. 1 and 2 may further include an adhesive layer 600.

The adhesive layer 600 is disposed on the bottom surface of the ceramic layer 700. Specifically, the adhesive layer 600 is disposed between the ceramic layer 700 and the second electrode 300b, between the ceramic layer 700 and the substrate 100, and between the ceramic layer 700 and the first electrode 300a . The adhesive layer 600 serves to fix the ceramic layer 700 to the substrate 100 and the first and second electrodes 300a and 300b.

In addition, the light emitting device package according to the embodiment shown in FIGS. 1 and 2 may further include a reflective member 800.

The reflective member 800 may be disposed on the second electrode 300b. Specifically, the reflective member 800 is disposed on a portion of the upper surface of the second electrode 300b where the ceramic layer 700 is not disposed, particularly at a portion where the wire w is connected to the upper surface of the second electrode 300b .

The reflective member 800 may fill a portion of the wire w.

The reflection member 800 may fill one end of the wire w connected to the upper surface of the second electrode 300b by the thickness of the ceramic layer 700. [ Here, the reflecting member 800 is buried as much as the thickness of the ceramic layer 700, and the upper surface of the reflecting member 800 may be disposed on the same plane as the upper surface of the ceramic layer 700. In this case, since the upper surface of the reflective member 800 reflects light with the same tendency as the upper surface of the ceramic layer 700, the light emitting device package according to the embodiment can obtain uniform light distribution. The upper surface of the reflective member 800 is not limited to the upper surface of the ceramic layer 700, and the upper surface of the reflective member 800 may be curved upward or downward. For example, a part of the cross section of the reflection member 700 may be polygonal, circular or elliptical, but is not limited thereto.

As another example, although not shown in the drawings, the thickness of the reflective member 800 may be thicker or thinner than the ceramic layer 700. [

The reflective member 800 may be a soft material and a white material. Specifically, the reflective material 800 may be a mixture of a thermosetting resin such as silicone or epoxy and a metallic material having high reflectance.

The reflective member 800 prevents light from the light emitting device 500 from being lost at a portion where the wire w and the second electrode 300b are connected.

The reflective member 800 may be disposed on the upper surface of the first electrode 300a between the light emitting device 500 and the ceramic layer 700 as shown in FIG. When the reflective member 800 is disposed on the upper surface of the first electrode 300a between the light emitting device 500 and the ceramic layer 700, the reflective member 800 is emitted from the light emitting device 500 to form the molding member 900 shown in FIG. The light reflected from the inside of the light emitting device 500 and reflected back toward the light emitting device 500 can be reflected again, thereby improving the luminous efficiency of the light emitting device package.

In addition, the light emitting device package according to the embodiment shown in FIGS. 1 and 2 may further include a molding member 900.

The molding member 900 may be disposed on the light emitting element 500.

The molding member 900 may be disposed on a part of the light emitting device 500, the wire w, and the first and second electrodes 300a and 300b. The molding member 900 may protect the light emitting device 500 from the external environment and stably connect the first and second electrodes 300a and 300b with the light emitting device 500. [ In addition, the molding member 900 may function as a lens for adjusting the directivity angle of the light emitted from the light emitting element 500.

The molding member 900 may have a hemispherical cross section and may be a light transmitting resin such as a silicone resin or an epoxy resin. The light transmitting resin may include a phosphor dispersed wholly or partially. The shape of the cross section of the molding member 900 is not limited thereto, and a polygon or a part of the cross section may have a concave or convex shape.

When the light emitting element 500 is a blue light emitting diode, the phosphor included in the light transmitting resin may be a garnet (YAG, TAG), a silicate, a nitride, an oxynitride, Or a combination thereof.

Natural light (white light) can be realized by including only a yellow phosphor in the translucent resin. However, a green phosphor or a red phosphor may be further included to improve the color rendering index and reduce the color temperature.

When various kinds of phosphors are mixed in the light transmitting resin, the addition ratio of the phosphors may be more green series phosphors than red series phosphors, and yellow series phosphors may be used more than green series phosphors. YAG, silicate, and oxynitride systems of the garnet system may be used as the yellow phosphor, silicate system and oxynitride system may be used as the green system phosphor, and nitrides may be used as the red system phosphor. have. A layer having a red-based phosphor, a layer having a green-based phosphor, and a layer having a yellow-based phosphor may be separately formed in addition to a mixture of various kinds of phosphors in the translucent resin.

4 to 7 are views for explaining a first method of manufacturing the light emitting device package shown in FIG. 4 (A) and 5 (B) are a sectional view and a front view, respectively.

First, as shown in FIGS. 4A and 4B, a ceramic layer 700 is formed on a substrate 100 on which a first electrode 300a and a second electrode 300b are disposed.

As a method of forming the ceramic layer 700 on the substrate 100 and the first and second electrodes 300a and 300b, a method of manufacturing the substrate 100 including the first and second electrodes 300a and 300b A ceramic layer 700 may be formed on the substrate 100 and the first and second electrodes 300a and 300b using a sintering process.

As shown in FIGS. 5A and 5B, the first and second electrodes 300a and 300b are plated with gold or silver. Specifically, the first and second electrodes 300a and 300b are plated with gold or silver to form the first and second electrodes 300a 'and 300b' where the ceramic layer 700 is not disposed. do. Not only the first and second electrodes 300a and 300b disposed on the upper surface of the substrate 100 but also the first and second electrodes 300a and 300b disposed on the lower surface of the substrate 100 are plated together However, only the first and second electrodes 300a and 300b disposed on the upper surface of the substrate 100 may be plated.

6A to 6B, the light emitting device 500 is disposed on the plated first electrode 300a ', and one end of the wire w is connected to the light emitting device 500 And the other end is connected to the plated second electrode 300b '. Here, two wires (w) are shown in the drawing, which means that the size of the light emitting device 500 is 1 mm or more in both width and height. When the number of the wires w is two, the current supply point supplied to the light emitting device 500 having a large size such as the size can be extended, and the current density in the light emitting device 500 can be made uniform. However, this is only one example, and the number of the wires w of the light emitting element 500 is not limited.

As shown in Figs. 7 (a) to 7 (b), a reflecting member 800 is formed. Specifically, a reflective member 800 for embedding the other end of the wire w connected to the plated second electrode 300b 'is formed. The reflective member 800 may be formed from the upper surface of the plated second electrode 300b 'by the thickness of the ceramic layer 700. [

The reflective member 800 may be formed by coating a plated second electrode 300b 'with a thermally curable resin such as silicone or epoxy mixed with a metallic material having high reflectance.

Here, as shown in FIGS. 8A and 8B, the reflective member 800 may also be formed on the plated first electrode 300a 'to form the light emitting device package shown in FIG. 3 . Specifically, the reflective member 800 can be formed on the upper surface of the plated first electrode 300a 'between the light emitting device 500 and the ceramic layer 700.

9 to 13 are views for explaining a second manufacturing method of the light emitting device package shown in FIG. 9 to 13, (a) is a sectional view and (b) is a front view.

First, as shown in FIGS. 9A and 9B, a substrate 100 including first and second electrodes 300a and 300b is formed.

10A and 10B, the first and second electrodes 300a and 300b disposed on the substrate 100 are coated with gold or silver plated first and second electrodes 300a and 300b, respectively, ', 300b'. Not only the first and second electrodes 300a 'and 300b' disposed on the upper surface of the substrate 100 but also the first and second electrodes 300a 'and 300b' disposed on the lower surface of the substrate 100 However, the first and second electrodes 300a 'and 300b' disposed on the upper surface of the substrate 100 may be plated.

A ceramic layer 700 is formed on the first and second electrodes 300a 'and 300b' plated with the substrate 100 as shown in FIGS. 11 (a) to 11 (b). Specifically, a ceramic layer 700 is formed on the upper surface of the substrate 100, and a ceramic layer 700 is formed on a portion of the plated first electrode 300a 'and a portion of the second electrode 300b' .

Here, the method of forming the ceramic layer 700 is a method in which a ceramic layer 700 composed of, for example, alumina or LTCC, which is the same as or different from the substrate 100, 1 and the second electrodes 300a 'and 300b'. Here, the adhesive may be applied to the bottom surface of the ceramic layer 700, and then the adhesive may be applied to the first and second electrodes 300a 'and 300b' plated with the substrate 100. [

12A to 12B, the light emitting device 500 is disposed on the plated first electrode 300a ', and one end of the wire w is connected to the light emitting device 500 And the other end is connected to the second electrode 300b 'plated with gold or silver.

As shown in Figs. 13 (a) to 13 (b), a reflecting member 800 is formed. Specifically, a reflective member 800 for embedding the other end of the wire w connected to the plated second electrode 300b 'is formed. The reflective member 800 may be formed from the upper surface of the plated second electrode 300b 'by the thickness of the ceramic layer 700. [

The reflective member 800 may be formed by coating a plated second electrode 300b 'with a thermally curable resin such as silicone or epoxy mixed with a metallic material having high reflectance.

Here, as shown in FIGS. 14A and 14B, the reflective member 800 may be formed on the plated first electrode 300a 'to form the light emitting device package shown in FIG. 3 . Specifically, the reflective member 800 can be formed on the upper surface of the plated first electrode 300a 'between the light emitting device 500 and the ceramic layer 700.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, It will be understood that various modifications and applications are possible. For example, each component specifically shown in the embodiments can be modified and implemented. It is to be understood that all changes and modifications that come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

100: substrate
300a, 300b: first and second electrodes
500: light emitting element
700: ceramic layer
800: reflective member

Claims (6)

Board;
First and second electrodes disposed on the substrate;
A light emitting element disposed on a portion of the first electrode;
A ceramic layer disposed on a portion of the second electrode;
One end connected to the light emitting element and the other end connected to another portion of the second electrode on which the ceramic layer is not disposed; And
A reflective member disposed on another portion of the second electrode;
Lt; / RTI >
Wherein the reflective member embeds one end of the wire,
And the upper surface of the reflective member is disposed on the same plane as the upper surface of the ceramic layer. The method according to claim 1,
And an upper surface of the reflective member is convex upward or downward. The method according to claim 1,
Wherein the thickness of the ceramic layer is greater than 0 and less than or equal to 0.1 mm. The method according to claim 1,
And an adhesive layer disposed between the second electrode and the ceramic layer. The method according to claim 1,
Wherein the ceramic layer is disposed on an upper surface of the substrate between the first electrode and the second electrode and on another portion of the first electrode,
Wherein the reflective member is disposed between the ceramic layer and the light emitting element. The method according to claim 1,
Wherein the light emitting element has a width and a length of 0.1 mm or more, respectively.

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