KR101610378B1

KR101610378B1 - Light emitting apparatus

Info

Publication number: KR101610378B1
Application number: KR1020090092802A
Authority: KR
Inventors: 백지흠
Original assignee: 엘지이노텍 주식회사
Priority date: 2009-09-30
Filing date: 2009-09-30
Publication date: 2016-04-08
Also published as: KR20110035189A

Abstract

A light emitting device is disclosed. The light emitting device includes an insulating substrate; A conductive pattern disposed on the insulating substrate; A light emitting element connected to the conductive pattern; And a heat dissipating unit disposed corresponding to the light emitting device and disposed under the insulating substrate and connected to the conductive pattern.

LED, package, flip, chip, via hole

Description

[0001] LIGHT EMITTING APPARATUS [0002]

Embodiments relate to light emitting devices, and more particularly, light emitting diode packages and light emitting diode arrays.

In general, a semiconductor light emitting device is an LED (Light Emitting Diode), which is an element used to transmit and receive signals by converting an electric signal into an infrared ray, a visible ray, or an ultraviolet ray using the characteristics of a compound semiconductor.

The LEDs can be packaged and applied to home electric appliances, remote controllers, electric sign boards, displays, various automation devices, electric lamps, and the like.

The embodiment is intended to provide a light emitting device having high productivity and being easily manufactured, having high reliability, having improved electrical characteristics, and high integration.

A light emitting device according to an embodiment includes an insulating substrate; A conductive pattern disposed on the insulating substrate; A light emitting element connected to the conductive pattern; And a heat dissipating unit disposed corresponding to the light emitting device and disposed under the insulating substrate and connected to the conductive pattern.

A light emitting device according to an embodiment includes an insulating substrate; A conductive pattern disposed on the insulating substrate; A plurality of light emitting elements connected to the conductive pattern; And a plurality of heat dissipating units connected to the conductive patterns, corresponding to the light emitting devices, and disposed under the insulating substrate.

The light emitting device according to the embodiment includes a heat dissipating portion connected to the conductive pattern. Particularly, the heat dissipating portion can be connected to the conductive pattern by the solder ball disposed in the through hole formed in the insulating substrate.

At this time, the solder ball may be disposed corresponding to the region where the conductive pattern and the light emitting element are bonded. Therefore, the light emitting device according to the embodiment can efficiently emit heat generated in the light emitting element by the heat dissipating portion, and can prevent performance deterioration due to heat generation.

In the light emitting device according to the embodiment, the light emitting element and the conductive pattern can be connected through a bump or the like without using wires or the like, and the conductive pattern can be connected to an external substrate or the like without using wires or the like.

Therefore, the light emitting device according to the embodiment has a higher contact characteristic, that is, a lower contact resistance than when using a wire, and can easily prevent a short circuit.

Therefore, the light emitting device according to the embodiment has improved electrical characteristics and high reliability.

Further, the heat dissipation part is made of a conductor, and a driving signal can be applied to the light emitting element through the heat dissipation part, the solder ball, and the conductive pattern. Therefore, the light emitting device according to the embodiment can integrate the heat dissipation structure and the wiring structure, and can be manufactured in a very small size.

In the description of the embodiments, each substrate, layer, region, wiring, hole, chip or electrode is referred to as being "on" or "under" each substrate, layer, Quot; on "and" under "include both being formed" directly "or" indirectly " . In addition, the upper or lower reference of each component is described with reference to the drawings. The size of each component in the drawings may be exaggerated for the sake of explanation and does not mean the size actually applied.

1 is an exploded perspective view illustrating a light emitting diode package according to an embodiment. 2 is a cross-sectional view illustrating one end surface of the light emitting diode package according to the embodiment. 3 is a cross-sectional view showing one end surface of the light emitting diode chip.

1 to 3, a light emitting diode package according to an embodiment includes an insulating substrate 100, a conductive pattern 200, a light emitting diode chip 300, a bump 400, a heat dissipating unit 500, 600).

The insulating substrate 100 has a plate shape. The insulating substrate 100 is an insulator. Examples of the material used for the insulating substrate 100 include a polyimide resin or a ceramic epoxy. At this time, when the insulating substrate 100 is made of a polyimide resin, the insulating substrate 100 has high heat resistance.

The insulating substrate 100 supports the conductive pattern 200, the light emitting diode chip 300, and the heat dissipating unit 500. The insulating substrate 100 is flexible. Alternatively, the insulating substrate 100 may be rigid.

The first through hole 110 and the second through hole 120 are formed in the insulating substrate 100. That is, the insulating substrate 100 includes a first through hole 110 and a second through hole 120.

The thickness of the insulating substrate 100 may be about 0.01 mm to about 5 mm. The insulating substrate 100 may have, for example, a rectangular plate shape and may have a cut side.

The conductive pattern 200 is disposed on the insulating substrate 100. The conductive pattern 200 covers the first through hole 110 and the second through hole 120.

The conductive pattern 200 is connected to the light emitting diode chip 300. More specifically, the conductive pattern 200 is connected to the light emitting diode chip 300 through the bump 400. That is, the conductive pattern 200 directly contacts the bump 400, and the bump 400 can directly contact the LED chip 300. Here, the meaning of contact may be interpreted to include both bonding, bonding and bonding.

The surface of the conductive pattern 200 may be surface-treated so as to easily bond to the bump 400. More specifically, a metal such as tin, gold, or the like may be plated on the surface of the conductive pattern 200.

The conductive pattern 200 includes a first conductive pattern 210 and a second conductive pattern 220.

The first conductive pattern 210 and the second conductive pattern 220 are disposed on the insulating substrate 100. The first conductive pattern 210 is spaced apart from the second conductive pattern 220. The first conductive pattern 210 is disposed next to the second conductive pattern 220.

The first conductive pattern 210 covers the first through hole 110. The first conductive pattern 210 includes the first connection part 211, the first wiring 212, and the first pad 213. The first connection part 211, the first wiring 212, and the first pad 213 may be integrally formed.

The first connection part 211 corresponds to the first through hole 110. The first connection part 211 is connected to the bump 400. More specifically, the first connection portion 211 is in contact with the bump 400. The first connection part 211 is overlapped with the light emitting diode chip 300.

The first wiring 212 connects the first connection part 211 and the first pad 213.

The first pad 213 is connected to the first connection part 211 by the first wiring 212. The first pad 213 is connected to an external device such as a printed circuit board or the like. The first pad 213 may be exposed to the outside.

The second conductive pattern 220 covers the second through hole 120. The second conductive pattern 220 includes the second connection part 221, the second wiring 222, and the second pad 223. The second connection part 221, the second wiring 222, and the second pad 223 may be integrally formed.

And the second connecting portion 221 corresponds to the second through hole 120. [ The second connection part 221 is connected to the bump 400. More specifically, the second connection portion 221 is in contact with the bump 400. The second connection part 221 overlaps the light emitting diode chip 300.

The second wiring 222 connects the second connection part 221 and the second pad 223.

The second pad 223 is connected to the second connection part 221 by the first wiring 212. The second pad 223 is connected to an external device such as a printed circuit board or the like. The second pad 223 may be exposed to the outside.

The conductive pattern 200 is formed of a conductive material. Examples of the material used for the conductive pattern 200 include copper, aluminum, tungsten, and alloys thereof.

In particular, the conductive pattern 200 may be made of copper, and the insulating substrate 100 may be made of a polyimide resin. In such a case, since copper and polyimide resin have similar thermal expansion coefficients, cracks due to temperature changes do not occur between the conductive pattern 200 and the insulating substrate 100.

The light emitting diode chip 300 is disposed on the conductive pattern 200. The light emitting diode chip 300 is disposed on the insulating substrate 100.

In addition, the LED chip 300 is disposed to overlap with the conductive pattern 200. The light emitting diode chip 300 is connected to the first connection part 211 and the second connection part 221. More specifically, the light emitting diode chip 300 is connected to the first connection part 211 and the second connection part 221 through the bump 400.

That is, the LED chip 300 is in direct contact with the bump 400, and as described above, the bump 400 contacts the first connection part 211 and the second connection part 221 directly The light emitting diode chip 300 is connected to the conductive pattern 200.

The light emitting diode chip 300 may be a compound semiconductor such as GaAs, AlGaAs, GaN, InGaN, and InGaAlP, and may be mounted in a chip form. The light emitting diode chip 300 may be a flip chip. In addition, the light emitting diode chip 300 may be a horizontal type LED chip or a vertical type LED chip.

3, the light emitting diode chip 300 includes a transparent substrate 310, an n-type cladding layer 320, a p-type cladding layer 330, an active layer 340, an n-type Ohmic electrode 350, a p-type ohmic electrode 360, and a p-type reflective electrode 370. The p-

The transparent substrate 310 is an insulator and is transparent. The transparent substrate 310 may be a sapphire substrate.

The n-type cladding layer 320 is disposed under the transparent substrate 310. The n-type cladding layer 320 has an n-type conductivity. For example, the n-type clad layer 320 may be an n-type GaN layer.

The p-type cladding layer 330 is disposed under the n-type cladding layer 320. The p-type cladding layer 330 is opposed to the n-type cladding layer 320. The p-type cladding layer 330 may be, for example, a p-type GaN layer.

The active layer 340 is interposed between the n-type cladding layer 320 and the p-type cladding layer 330. The active layer 340 has a single quantum well structure or a multiple quantum well structure. The active layer 340 may be formed of a period of an InGaN well layer and an AlGaN barrier layer, or a period of an InGaN well layer and a GaN barrier layer. The light emitting material of the active layer 340 may have a luminescent wavelength, Wavelength, and the like.

The n-type Ohmic electrode 350 is disposed under the n-type cladding layer 320. The n-type Ohmic electrode 350 is connected to the n-type cladding layer 320. The n-type Ohmic electrode 350 may be disposed on the same plane as the active layer 340.

The p-type ohmic electrode 360 is disposed under the p-type cladding layer 330. The p-type ohmic electrode 360 is connected to the p-type cladding layer 330.

The p-type reflective electrode 370 is disposed between the p-type ohmic electrode 360 and the p-type cladding layer 330. The p-type reflective electrode 370 reflects light generated from the active layer 340.

The bumps 400 are disposed between the light emitting diode chip 300 and the conductive pattern 200. More specifically, the bump 400 is disposed corresponding to the first connection part 211 and the second connection part 221. [ In more detail, the bumps 400 may be disposed corresponding to the first through holes 110 and the second through holes 120.

The bump 400 directly contacts the light emitting diode chip 300 and the conductive pattern 200. More specifically, the bump 400 is bonded to the light emitting diode chip 300 and the conductive pattern 200. More specifically, the bump 400 is bonded to the first connection part 211 and the second connection part 221 and is bonded to the n-type ohmic electrode 350 and the p-type ohmic electrode 360.

At this time, the conductive pattern 200 and the LED chip 300 may be bonded together by the pressure applied in the vertical direction with the bump 400 interposed therebetween. The first interface at which the conductive pattern 200 and the bump 400 are in contact with each other faces the second interface at which the LED chip 300 and the bump 400 are in contact with each other, And may be parallel to the interface.

The bumps 400 have a ball shape or a lump shape. More specifically, the bump 400 has a compressed ball shape. That is, the bump 400 may include a flat top surface and a flat bottom surface. That is, the bump 400 may have a plate shape having an upper surface and a lower surface. The upper surface of the bump 400 may be in contact with the conductive pattern 200 and the lower surface of the bump 400 may be in contact with the LED chip 300. The thickness of the bump 400 is substantially equal to the distance between the conductive pattern 200 and the LED chip 300.

The bump 400 includes a first bump 410 and a second bump 420.

The first bump 410 is bonded to the first conductive pattern 210 and is bonded to the LED chip 300 at the same time. Particularly, the first bump 410 is bonded to the first connection part 211 and is bonded to the n-type Ohmic electrode 350 at the same time.

The first connection part 211 and the n-type Ohmic electrode 350 are physically and electrically connected to each other by the first bump 400.

The second bump 420 is bonded to the second conductive pattern 220 and bonded to the LED chip 300. Particularly, the second bump 420 is bonded to the second connection part 221 and is simultaneously bonded to the p-type Ohmic electrode 360.

The second connection part 221 and the p-type Ohmic electrode 360 are physically and electrically connected to each other by the second bump 420.

The bottom surface of the first bump 410 is bonded to the top surface of the n-type ohmic electrode 350 and the bottom surface of the second bump 420 is bonded to the top surface of the p-

The bump 400 is a low-resistance conductor. Examples of the material used for the bump 400 include gold, silver, lead, copper, aluminum, and their alloys.

The heat dissipating unit 500 is disposed below the insulating substrate 100. And is connected to the conductive pattern 200.

The heat dissipation unit 500 dissipates heat generated from the light emitting diode chip 300 to the outside. The heat dissipation unit 500 includes a metal or the like having a high thermal conductivity. Examples of materials used for the heat dissipation unit 500 include aluminum and the like.

The heat dissipation unit 500 may be bonded to the insulating substrate 100.

The heat dissipation unit 500 includes a conductor. More specifically, the heat dissipation unit 500 may be formed of a conductive material. The heat dissipation unit 500 may be a conductive member.

The heat dissipation unit 500 may be electrically and physically connected to the conductive pattern 200. More specifically, the heat dissipation unit 500 may be electrically and physically connected to the conductive pattern 200 by the solder ball 600.

The heat dissipation unit 500 includes a first heat dissipation unit 510 and a second heat dissipation unit 520.

The first heat dissipation unit 510 and the second heat dissipation unit 520 are spaced apart from each other. In addition, the first heat dissipation unit 510 and the second heat dissipation unit 520 are arranged side by side.

The first heat radiation part 510 is disposed corresponding to the first conductive pattern 210. The first heat dissipation unit 510 faces the first conductive pattern 210 with the insulating substrate 100 interposed therebetween. The first heat radiation part 510 is connected to the first conductive pattern 210.

The second heat radiation part 520 is disposed corresponding to the second conductive pattern 220. The second heat radiation part 520 faces the second conductive pattern 220 with the insulating substrate 100 interposed therebetween. The second radiation part 520 is connected to the second conductive pattern 220.

The solder ball 600 is disposed between the conductive pattern 200 and the heat dissipation unit 500. The solder ball 600 connects the conductive pattern 200 and the heat dissipation unit 500. More specifically, the solder ball 600 electrically and physically connects the conductive pattern 200 and the heat dissipation unit 500. The solder ball 600 includes a conductor and has a high thermal conductivity.

The solder ball 600 is disposed inside the first through hole 110 and the second through hole 120. The solder ball contacts the lower surface of the conductive pattern 200 and contacts the upper surface of the heat dissipation unit 500.

For example, the solder ball 600 includes a first solder ball 610 and a second solder ball 620.

The first solder ball 610 is disposed inside the first through hole 110. The first solder ball 610 connects the first conductive pattern 210 and the first heat dissipation unit 510. More specifically, the first solder ball 610 connects the first connection part 211 and the first heat dissipation part 510. The first solder ball 610 may be filled in the first through hole 110. The first solder ball 610 may be directly bonded to the lower surface of the first conductive pattern 210 and the upper surface of the first heat dissipation unit 510.

The second solder ball 620 is disposed inside the second through hole 120. The second solder ball 620 connects the second conductive pattern 220 and the second heat dissipation unit 520. More specifically, the second solder ball 620 connects the second connection unit 221 and the second heat dissipation unit 520. The second solder ball 620 may be filled in the second through hole 120. The second solder ball 620 may be directly bonded to the lower surface of the second conductive pattern 220 and the upper surface of the second heat dissipation unit 520.

The light emitting diode package according to the embodiment may include a solder resist and a lens portion.

The solder resist covers the conductive pattern 200. The solder resist is disposed on the insulating substrate 100. The solder resist is an insulating layer, and the conductive pattern 200 is insulated. Further, the solder resist protects the conductive pattern 200 from foreign substances, moisture, or the like.

The lens unit is disposed on the insulating substrate 100. The lens unit is disposed on the light emitting diode chip 300. The lens unit improves the characteristics of light emitted from the LED chip 300.

In addition, the light emitting diode package according to the embodiment may further include a light conversion layer. The light conversion layer may include a phosphor. The light conversion layer converts the color of light emitted from the light emitting diode chip 300.

For example, the light emitting diode chip 300 may be a blue light emitting diode chip 300 for generating blue light, and the light converting layer may include a yellow phosphor. Accordingly, the light emitting diode package according to the embodiment can emit white light.

In the light emitting diode package according to the embodiment, the conductive pattern 200 and the light emitting diode chip 300 are connected by the bump 400. The bump 400 has a higher contact characteristic, i.e., a lower resistance, than a conventional wire. In addition, the bumps 400 can more easily prevent shorting than conventional wires.

Particularly, since the bump 400 has a pressed ball shape, it has a much lower resistance than a conventional wire. That is, an electric signal for driving the light emitting diode chip 300 is transmitted from the conductive pattern 200 to the LED chip 300 through a path corresponding to the thickness of the bump 400. At this time, since the thickness of the bump 400 is much smaller than that of the conventional wire, the resistance between the LED chip 300 and the conductive pattern 200 is very low.

Accordingly, the light emitting diode package according to the embodiment has improved electrical characteristics and high reliability.

Since the insulating substrate 100 is flexible, the light emitting diode package according to the embodiment can be flexible. Accordingly, the light emitting diode package according to the embodiment can be modified into various forms. In addition, since the light emitting diode package according to the embodiment is flexible, it can be easily installed in an external device such as a printed circuit board.

The heat dissipation unit 500 may be connected to an external device such as a printed circuit board. An electrical signal for driving the light emitting diode chip 300 is transmitted through the heat dissipation unit 500, the solder ball 600, the conductive pattern 200, and the bump 400, May be applied to the chip 300.

The heat generated from the light emitting diode chip 300 is discharged through the bump 400, the conductive pattern 200, the solder ball 600, and the heat dissipation unit 500. At this time, the solder ball 600 may be disposed corresponding to a region where the light emitting diode chip 300 and the conductive pattern 200 are bonded. That is, the solder ball 600 may be disposed corresponding to the bumps 400.

Accordingly, the heat generated from the LED chip 300 can be efficiently discharged through the bumps 400, the conductive pattern 200, the solder ball 600, and the heat dissipation unit 500.

The light emitting diode package according to the embodiment disposes the bump 400, the conductive pattern 200, the solder ball 600, and the heat dissipation unit 500 to correspond to each other. Therefore, the light emitting diode package according to the embodiment has a high degree of integration.

The light emitting diode chip 300 may be connected to an external printed circuit board through the first pad 213 and the second pad 223 or may be connected to an external printed circuit board Can be connected.

At this time, the light emitting diode package according to the embodiment does not need to be connected to an external device or the like by a wire or the like.

Therefore, the light emitting diode package according to the embodiment has a higher contact characteristic, that is, a lower contact resistance than when using a wire, and can easily prevent a short circuit.

Therefore, the light emitting diode package according to the embodiment has improved electrical characteristics and high reliability.

4 is a cross-sectional view illustrating one end surface of a light emitting diode array according to an embodiment. The description of the light emitting diode package described above can be essentially combined with the description of the light emitting diode array of this embodiment except for the changed portions.

Referring to FIG. 4, the light emitting diode array according to the embodiment may have a structure in which a plurality of light emitting diode packages as described above are coupled.

The light emitting diode array according to the embodiment includes one insulating substrate 101 and a plurality of light emitting diode chips 300.

The insulating substrate 101 has a large planar surface. In addition, the insulating substrate 101 includes a plurality of first through holes and a plurality of second through holes.

A conductive pattern 200 is disposed on the insulating substrate 100. The conductive pattern 200 may be disposed on the entire upper surface of the insulating substrate 100. In addition, the conductive pattern 200 may have a complicated structure.

The conductive pattern 200 may connect the light emitting diode chips 300 to each other. In addition, driving elements for driving the light emitting diode chips 300 may be connected to the conductive pattern 200.

The light emitting diode chips 300 are disposed on the insulating substrate 101. More specifically, the light emitting diode chips 300 are disposed on the conductive pattern 200. The light emitting diode chips 300 are connected to the conductive pattern 200.

Solder balls 600 are disposed in the first through holes and the second through holes, respectively. The solder balls 600 connect the conductive pattern 200 and the heat dissipation units 500.

The heat sinks 500 are disposed under the insulating substrate 101. The heat dissipation units 101 are connected to the light emitting diode chips 300 by the solder ball 600 and the conductive pattern 200. The heat dissipation units 500 efficiently dissipate the heat generated from the light emitting diode chips 300.

The light emitting diode chips 300 may be connected to each other by the conductive pattern 200. More specifically, the light emitting diode chips 300 may be connected in series and / or in parallel with each other by the conductive pattern 200.

In addition, the light emitting diode chips 300 may be connected to the driving elements by the conductive pattern 200.

In addition, the light emitting diode array according to the embodiment disposes a plurality of light emitting diode chips 300 on one insulating substrate 101. Further, on the insulating substrate 101, driving elements for driving the light emitting diode chips 300 may be further disposed.

The heat dissipation units 500 are disposed below the insulation substrate 101 and are connected to the light emitting diode chips 300 disposed on the insulation substrate 101 by the solder balls 600.

Therefore, the light emitting diode array according to the embodiment has a high degree of integration and can realize a surface light source of high brightness.

The light emitting diode array according to the embodiment may have a form of a light emitting diode package. In addition, the light emitting diode array and the light emitting diode package according to the embodiment are light emitting devices.

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

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.

1 is an exploded perspective view illustrating a light emitting diode package according to an embodiment.

2 is a cross-sectional view illustrating one end surface of the light emitting diode package according to the embodiment.

3 is a cross-sectional view showing one end surface of the light emitting diode chip.

4 is a cross-sectional view illustrating one end surface of a light emitting diode array according to an embodiment.

Claims

An insulating substrate;

A conductive pattern disposed on the insulating substrate;

A light emitting element connected to the conductive pattern;

A heat dissipating unit disposed over the light emitting device and disposed under the insulating substrate, the heat dissipating unit being connected to the conductive pattern;

A solder ball connecting the conductive pattern and the heat dissipation unit and disposed to overlap the heat dissipation unit; And

And a bump interposed between the light emitting element and the conductive pattern, the bump being in direct contact with the light emitting element and the conductive pattern, and being disposed over the solder ball.

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The semiconductor device according to claim 1, wherein the insulating substrate includes a through hole,

The solder ball is disposed inside the through hole,

Wherein the solder ball contacts the lower surface of the conductive pattern and the upper surface of the heat dissipation unit.

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The light emitting device according to claim 1,

An n-type cladding layer and a p-type cladding layer opposed to each other;

An active layer interposed between the n-type cladding layer and the p-type cladding layer;

An n-type Ohmic electrode connected to the n-type cladding layer; And

And a p-type Ohmic electrode connected to the p-type cladding layer,

The bump

A first bump contacting the n-type Ohmic electrode; And

And a second bump contacting the p-type Ohmic electrode,

The conductive pattern

A first conductive pattern contacting the first bump; And

And a second conductive pattern spaced apart from the first conductive pattern and contacting the second bump.

The light emitting device according to claim 1, wherein the insulating substrate comprises a polyimide resin, and the conductive pattern comprises copper.

The light emitting device of claim 1, wherein the heat dissipation unit is a conductor, and the light emitting device receives a driving signal through the heat dissipation unit.

The method of claim 1, wherein the conductive pattern includes a first conductive pattern and a second conductive pattern spaced apart from each other,

The heat-

A first radiator connected to the first conductive pattern; And

And a second radiation part connected to the second conductive pattern.

An insulating substrate;

A conductive pattern disposed on the insulating substrate;

A plurality of light emitting elements connected to the conductive pattern; And

And a plurality of heat dissipation parts connected to the conductive pattern and disposed over the light emitting devices and disposed under the insulating substrate,

Wherein the insulating substrate includes a plurality of through holes arranged in an overlapping region of the conductive pattern and the light emitting devices,

And a plurality of solder balls connecting the heat dissipation unit and the conductive pattern and disposed over the heat dissipation unit,

And a plurality of bumps interposed between the light emitting element and the conductive pattern, the plurality of bumps being in direct contact with the light emitting element and the conductive pattern, and disposed over the solder balls.

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