KR20140053513A

KR20140053513A - Light emitting device module and head lamp including the same

Info

Publication number: KR20140053513A
Application number: KR1020120119534A
Authority: KR
Inventors: 조윤민
Original assignee: 엘지이노텍 주식회사
Priority date: 2012-10-26
Filing date: 2012-10-26
Publication date: 2014-05-08
Also published as: KR101972047B1

Abstract

An embodiment includes a support substrate; A first insulating layer and a second insulating layer, and a conductive layer disposed between the first insulating layer and the second insulating layer, wherein a part of the contact region is in contact with the first open region A flexible substrate disposed thereon; A light emitting element disposed on the support substrate in a first open region of the flexible substrate; And a connector connecting portion disposed in a region of the flexible substrate that is not in contact with the supporting substrate.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a light emitting diode (LED)

Embodiments relate to a light emitting device module and a headlamp including the same.

BACKGROUND ART Light emitting devices such as light emitting diodes and laser diodes using semiconductor materials of Group 3-5 or 2-6 group semiconductors have been widely used for various colors such as red, green, blue, and ultraviolet And it is possible to realize white light rays with high efficiency by using fluorescent materials or colors, and it is possible to realize low power consumption, semi-permanent life time, quick response speed, safety, and environment friendliness compared to conventional light sources such as fluorescent lamps and incandescent lamps It has the advantage of gender.

Therefore, a transmission module of the optical communication means, a light emitting diode backlight replacing a cold cathode fluorescent lamp (CCFL) constituting a backlight of an LCD (Liquid Crystal Display) display device, a white light emitting element capable of replacing a fluorescent lamp or an incandescent lamp Diode lighting, automotive headlights, and traffic lights.

1 is a view schematically showing a structure of a conventional light emitting device module.

The light emitting device module 100 may be used as a light source in a head lamp or the like. The conductive layer 120 may be disposed on the substrate 110 and the light emitting device 10 may be disposed on the conductive layer 120. The conductive layer 120 is connected to the connector 170 through the flexible circuit board 150 and can receive current.

However, the conventional light emitting device module has the following problems.

The flexible circuit board 150 must be in electrical contact with the conductive layer 120 in order to receive a current or a drive signal from the connector and transmit the current or drive signal to the light emitting element 10 and the solder 160 is electrically connected to the conductive layer 120 And the flexible circuit board 150 can be brought into electrical contact with each other.

At this time, when the light emitting element module is used, heat is emitted from the light emitting element 10 or the like, and the solder can be melted by heat. Such melting of the solder may lead to the problem of durability of the light emitting device module. Particularly, in the case of a headlamp for a vehicle which can be used for a long time, stable connection between the conductive layer and the circuit board due to the high temperature environment and heat generation of the light emitting element is particularly important.

An embodiment provides a light emitting device module in which a circuit board is stably connected to a head lamp or the like.

Another embodiment includes a first insulating layer and a second insulating layer, and a conductive layer disposed between the first insulating layer and the second insulating layer, wherein the first region includes a first open region, A flexible substrate including a second region spaced apart by a predetermined distance; A support substrate in contact with the flexible substrate in the first region; A light emitting element in contact with the supporting substrate in the first open region; And a connector connection portion that contacts the flexible substrate in the second region.

Another embodiment includes a heat dissipation unit; A light source including the light emitting device module described above, wherein the supporting substrate of the light emitting module is in thermal contact with the heat dissipating unit; Reflective portion; And a headlamp including a lens.

The support substrate may be made of ceramic or metal.

At least one of the first insulating layer and the second insulating layer may include a polyimide.

The conductive layer may comprise copper.

The flexible substrate can be in surface contact with the support substrate.

A region where the support substrate and the flexible substrate are in contact with each other and a non-contact region where the connector connection portion is disposed may be spaced apart from each other.

The flexible substrate may be fixed to the support substrate with an epoxy-based or silicone-based adhesive.

The light emitting device module may further include a barrier disposed around the first open area.

The barrier includes a first barrier and a second barrier separated from each other, and the light emitting element may be electrically connected to the first barrier and the second barrier, respectively.

The light emitting device is bonded to the first barrier and the second barrier respectively with wires, and the height of the first barrier and the second barrier in the bonding area may be lower than the height in the non-bonding area.

And a region in which a part of the supporting substrate is exposed in an edge region of the barrier, and a temperature measuring sensor may be disposed in the exposed region.

In the non-contact area where the connector connection part is disposed, the conductive layer can be exposed in at least two areas.

The flexible substrate may be straight or curved.

A plurality of light emitting elements may be disposed in a first open region of the flexible substrate, and the plurality of light emitting elements may be connected in parallel to each other.

The support substrate may have a thickness of 0.6 millimeters to 5 millimeters.

The first insulating layer and the second insulating layer may each have a thickness of 35 micrometers to 3 millimeters.

The conductive layer may have a thickness of 35 micrometers to 350 micrometers.

The supporting substrate may be disposed in the direction of the first insulating layer of the flexible circuit board and the connector connecting portion may be disposed in the direction of the second insulating layer of the flexible circuit board.

In the light emitting device module according to the embodiment, since the flexible circuit board is in surface contact with the supporting substrate on which the light emitting device is disposed, durability of the adhesive can be maintained even when heat is generated during driving of the light emitting device.

1 is a schematic view showing a structure of a conventional light emitting device module,
2 is a view schematically showing a structure of an embodiment of a light emitting device module,
FIG. 3 is a view showing a structure of a support substrate and a flexible substrate of the light emitting device module of FIG. 2,
4A to 4C are a plan view, a sectional view and a bottom view of the light emitting device module of FIG. 2,
5A is a plan view of the 'A' region of FIG. 4A,
5B is a cross-sectional view taken along line I-I 'of FIG. 5A,
FIG. 6 is a view showing an embodiment of the light emitting device of FIG. 2,
7 is a view showing an embodiment of a headlamp.

BRIEF DESCRIPTION OF THE DRAWINGS The above and other objects, features and advantages of the present invention will be more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which: FIG.

In the description of the embodiment according to the present invention, in the case of being described as being formed "on or under" of each element, the upper (upper) or lower (lower) or under are all such that two elements are in direct contact with each other or 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.

2 is a view schematically showing a structure of an embodiment of a light emitting device module.

The light emitting device module 200 according to the embodiment includes a support substrate 210, a flexible circuit board 250 that is in surface contact with the support substrate 210, And a connector connection part 270 disposed in the second area.

(A region in contact with the light emitting element) of the flexible circuit board 250 to which the light emitting element 10 is to be contacted and a connector connecting portion 270 to be brought into contact with the connector, The support substrate 210 is in contact with the flexible circuit board 250 in the first area due to the surface contact, not the contact by the ball-shaped solder. The connector connection portion 270 may be a connector terminal or the like.

The support substrate 210 and the connector connection portion 270 are arranged in opposite directions with respect to the flexible circuit substrate 250. Referring to the following description of the flexible circuit substrate 250, The supporting substrate 210 may be disposed in the direction of the first insulating layer 252 of the flexible circuit board 250 and the connector connecting portion 270 may be disposed in the direction of the second insulating layer 256 of the flexible circuit board 250. Further, the light emitting element 10 is disposed in the same direction as the connector connecting portion 270 with respect to the flexible circuit board 250.

FIG. 3 is a view showing a structure of a support substrate and a flexible substrate of the light emitting device module of FIG. 2;

The supporting substrate 210 and the flexible circuit board 250 are in surface contact with each other in a partial area and the flexible circuit board 250 is formed by the first insulating layer 252 and the second insulating layer 256 and the first insulating layer 252 And a conductive layer 254 disposed between the second insulating layer 256 and the second insulating layer 256. A first open region in which the support substrate 210 is exposed may be formed in a region where the flexible circuit substrate 250 contacts the support substrate 210. [ Although the flexible circuit board 250 is shown as a straight line, it may be curved.

The first open region is a region in which the light emitting device is to be placed in contact with the support substrate 210 as described later. The support substrate 210 may be made of ceramic or metal and may have _a thickness t _a of 0.6 millimeters to 5 millimeters. If the supporting substrate 210 is too thick, the volume of the light emitting device module may increase and the material cost may increase. If the supporting substrate 210 is too thin, it may be difficult to stably support the light emitting device module.

The first insulating layer 252 and the second insulating layer 256 may be made of an insulating material and may include polyimide, and each may have a thickness of 35 micrometers to 3 millimeters. If the thicknesses t _b and t _{d of} the first insulating layer 252 and the second insulating layer 256 are too thin, the insulating effect may not be sufficient. If the thicknesses are too large, May occur.

The conductive layer 254 may be made of a conductive material, and may be specifically a metal or a conductive alloy. More specifically, the conductive layer 254 may include copper (Cu), and may have a thickness of 30 micrometers to 350 micrometers. If the thickness t _c of the conductive layer 254 is too small, it may be difficult to stably supply the current. If the thickness is too large, the material ratio may increase and the volume or thickness of the light emitting device module may increase.

The support substrate 210 and the flexible circuit board 250 may be fixed with an adhesive 240 which may be a conductive or nonconductive adhesive and more specifically an epoxy or silicone adhesive . Since the flexible circuit board 250 is in surface contact with the support substrate 210 on which the light emitting element 10 is disposed, the light emitting element module 100 according to the present embodiment can prevent the heat generated when the light emitting element 10, The durability of the above-described adhesive 240 can be maintained.

3, the first region of the flexible circuit board 250 is mainly shown. Hereinafter, a structure of the entire light emitting device module will be described.

4A to 4C are a plan view, a sectional view and a bottom view of the light emitting device module of FIG.

A first open area is formed in the flexible circuit board 250 to expose the supporting substrate 210. A plurality of light emitting devices may be disposed in the first open area as described later. A pair of barriers 231 and 232 are disposed around the first open area, and the barriers 231 and 232 may be disposed around the light emitting device and may be electrically connected to the respective electrodes of the light emitting device. The device and the wire can be protected.

The barriers 231 and 232 may be electrically separated from each other and at least one pair may be disposed around the light emitting device, and the specific shape may be different from that shown in FIG. In FIG. 4A, a second open region may be formed in the edge region of the barrier 231 or 232 to expose a part of the support substrate. A part of the support substrate exposed through the second open region may be provided with a temperature measurement sensor And the heat generation of the light emitting element or the light emitting element module can be measured.

5A is a plan view of the 'A' region of FIG. 4A, and FIG. 5B is a sectional view of the I-I 'axis of FIG. 5A. The arrangement of the light emitting device and the barrier will be described in detail with reference to FIGS. 5A and 5B.

A plurality of (four in this embodiment) light emitting elements 10 are arranged in an open region (first open region) where a part of the supporting substrate 210 is opened, and the barriers 231 and 232 are connected to the light emitting element 10 and the wire 15 as well as the wire.

The first and second barriers 231 and 232 may be referred to as a first barrier 231 and a second barrier 232 respectively and the first barrier 231 and the second barrier 232 may be referred to as a first barrier 231 and a second barrier 232, It can be electrically connected, and specifically, can be bonded with the wire 15. Barriers 231 and 232 may be made of polymer, ceramics, metal, or the like, and in particular, the area to be wire-bonded may be made of a conductive material.

The areas to be bonded to the wires in the first barrier 231 and the second barrier 232 may be referred to as bonding areas 231a and 232a and the height h of the bonding area 232a as shown in FIG. _a ) may be lower than the height h _b of the unbonded areas 231b and 232b.

In the present embodiment, four light emitting devices are disposed, and each of the light emitting devices may be connected in parallel to each other. Each electrode of the light emitting device 10 is connected to the first barrier 231 and the second barrier 232 .

Four regions 260a to 260d in which the conductive layer is exposed are formed under the barriers 231 and 232. Zener diodes and the like may be disposed in two of the regions.

The conductive layers are exposed in the two regions 265a and 265b below the four regions 260a to 260d described above with reference to FIG. 4A, which can serve as test points. That is, the two barriers 231 and 232 respectively connected to the +/- electrodes of the light emitting element 10 should be connected to the conductive layer exposed in the third open region, and the conductive layers exposed at the two test points Can be confirmed.

In the third open area, the above-described connector connecting portion 270 is disposed, so that the connector can be electrically connected to the conductive layer.

Between the two regions 265a and 265b serving as test points and the third open region, four regions 270a to 270d, in which the conductive layer is exposed, are disposed. The two edges 270a and 270d of the four regions may be electrically connected to the +/- electrodes respectively and the remaining two regions 270b and 270c may be thermally variable resistors for thermal measurement. However, it is not limited thereto.

FIG. 6 is a view showing an embodiment of the light emitting device of FIG. 2. FIG.

A light emitting diode (LED) may be used as the light emitting element 10 and may be a blue light emitting diode or a light emitting diode that emits ultraviolet rays or deep ultraviolet rays according to a wavelength range of emitted light. A horizontal type light emitting device, a vertical type light emitting device, or a flip chip type light emitting device.

6 illustrates a horizontal type light emitting device as an example. When the light emitting device 10 is a light emitting diode, the buffer layer 12, the first conductivity type semiconductor layer 13a, and the active layer 13b are formed on the substrate 11, And a light emitting structure 13 including a second conductive semiconductor layer 13c.

The first conductive semiconductor layer 13a may be formed of a semiconductor compound, for example, a compound semiconductor such as a group III-V element or a group II-VI element. Also, the first conductivity type dopant may be doped. When the first conductivity type semiconductor layer 13a is an n-type semiconductor layer, the first conductivity type dopant may include Si, Ge, Sn, Se, and Te as an n-type dopant.

The first conductive semiconductor layer 13a may be formed of only the first conductive semiconductor layer or may include an undoped semiconductor layer below the first conductive semiconductor layer, but the present invention is not limited thereto.

The non-conductive semiconductor layer is formed to improve the crystallinity of the first conductive type semiconductor layer, and the non-conductive semiconductor layer has a lower electrical conductivity than the first conductive type semiconductor layer without doping the n-type dopant. May be the same as the first conductivity type semiconductor layer 13a.

The active layer 13b may be formed on the first conductivity type semiconductor layer 13a. In the active layer 13b, electrons injected through the first conductive type semiconductor layer 13a and holes injected through the second conductive type semiconductor layer 13c formed thereafter are mutually combined to form an energy band unique to the material of the active layer 13b Is a layer that emits light having energy determined by the energy.

The active layer 13b may be formed of at least one of a double heterojunction structure, a single well structure, a multi-well structure, a quantum-wire structure, or a quantum dot structure. For example, the active layer may be formed by implanting trimethylgallium gas (TMGa), ammonia gas (NH ₃ ), nitrogen gas (N ₂ ), and trimethyl indium gas (TMIn) to form a multiple quantum well structure. It is not.

The well layer / barrier layer of the active layer 13b may be formed of any one of a pair of InGaN / GaN, InGaN / InGaN, GaN / AlGaN, InAlGaN / GaN, GaAs (InGaAs) / AlGaAs, GaP (InGaP) But the present invention is not limited thereto. The well layer may be formed of a material having a band gap smaller than the band gap of the barrier layer.

A conductive clad layer (not shown) may be formed on and / or below the active layer 13b. The conductive cladding layer may be formed of a semiconductor having a band gap wider than the band gap of the barrier layer of the active layer 13b. For example, the conductive clad layer may comprise GaN, AlGaN, InAlGaN or a superlattice structure. Further, the conductive clad layer may be doped with n-type or p-type.

The second conductivity type semiconductor layer 13c may be formed on the active layer 13b. The second conductive semiconductor layer 13c may be formed of a semiconductor compound, for example, a compound semiconductor such as a Group III-V or a Group II-VI doped with a second conductive dopant. The second conductivity type semiconductor layer 13c may be formed of, for example, In _x Al _y Ga ₁ _-x- _y N (0? X? 1, 0? _Y? 1, 0? _X + y? 1) And the like. When the second conductive semiconductor layer 13c is a p-type semiconductor layer, the second conductive dopant may include, but not limited to, Mg, Zn, Ca, Sr, and Ba as p-type dopants.

A transparent conductive layer 14 may be disposed on the second conductive semiconductor layer 13c to uniformly supply a current to the second conductive semiconductor layer 13c. The first conductive semiconductor layer 13a and the transparent conductive layer 14 may have a first electrode 12a and a second electrode 14a, respectively.

Here, 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, as described above. In addition, a third conductive semiconductor layer including an n-type or p-type semiconductor layer may be formed on the first conductive semiconductor layer. Accordingly, the light emitting device may include at least one of np, pn, npn, And may include any one of them.

4C, four through holes 250a are arranged on the supporting substrate 210 and two through holes 250b are arranged on the flexible circuit substrate 250. [ The above-described through holes 250a and 250b may be inserted with a fixing unit for fixing the light emitting element module to a heat dissipating unit or the like to be described later. The through holes 250a may be formed through the support substrate 210 and the flexible circuit board 250 and the other through holes 250b may be formed only through the flexible circuit board 250. [

In the flexible circuit board 250, two third open regions are disposed in a region opposite to the open region. In the third open region, the above-described connector connection portion is mounted and the connector can be connected. The third open region is distinguished from the first open region and the second open region by the third open region. In the third open region, the first open region and the second open region are exposed from the point that the conductive layer in the flexible circuit board is exposed And can be distinguished from the second open area.

7 is a view showing an embodiment of a headlamp.

7, the head lamp 400 includes a light emitting element module 200, reflectors 420 and 425, a lens 430, a lens cover 435, a housing 440, (450). &Lt; / RTI >

The light emitting device module 200 is disposed in thermal contact with the heat dissipating unit 450, and the specific configuration thereof is the same as described above. The reflectors 420 and 425 are fixed to the housing 440 and have a cross section in the form of a dome or other curved surface so that the light emitted from the light emitting device module 20 can be advanced from the head lamp 400 to the front of the vehicle .

The lens cover portion 435 is fixed to the housing 440, and the lens 430 can be fixed. The lens cover portion 435 may be formed of an injection molded product to house the lens 430 therein and the lens 435 may advance the light emitted from the light emitting module 200 to the front surface thereof, have. The housing 440 and the lens cover part 435 can be changed in design to change the shape of the shape of the lens 430 in order to change the path of light emitted from the light emitting device module 200 and fix the lens 430.

The heat dissipation unit 450 is made of a material having excellent thermal conductivity, such as metal, by emitting heat generated from the light emitting device or the like in thermal contact with the light emitting device module 200, and a plurality of grooves are formed in the lower portion.

In the head lamp 400 according to the present embodiment, since the flexible circuit board is in surface contact with the supporting substrate in the light emitting element module 200, the durability of the adhesive is maintained even when heat is generated during driving of the light emitting element, Can be kept constant.

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 exemplary 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.

10: light emitting element 11: substrate
12: buffer layer 13: light emitting structure
100, 200: light emitting element module 110, 210: support substrate
120: conductive layer 150, 250: flexible circuit board
160: Solder 170, 270: Connector connection
231, 231: first and second barriers 231a. 232a: bonding area
232a, 232b: non-bonding areas 250a, 250b: through holes
252, 256: first and second insulating layers 254: conductive layer
400: head lamp 420, 425:
430: Lens 435: Lens cover part
440: housing 450:

Claims

A support substrate;
A first insulating layer and a second insulating layer, and a conductive layer disposed between the first insulating layer and the second insulating layer, wherein a part of the contact region is in contact with the first open region A flexible substrate disposed thereon;
A light emitting element disposed on the support substrate in a first open region of the flexible substrate; And
And a connector connection portion disposed in a region of the flexible substrate that is not in contact with the support substrate.

The method according to claim 1,
Wherein the supporting substrate is made of ceramic or metal.

The method according to claim 1,
Wherein at least one of the first insulating layer and the second insulating layer comprises a polyimide.

The method according to claim 1,
Wherein the conductive layer comprises copper.

The method according to claim 1,
Wherein the flexible substrate is in surface contact with the support substrate.

The method according to claim 1,
Wherein a region in which the support substrate and the flexible substrate are in contact with each other and a noncontact region in which the connector connection portion is disposed are spaced apart from each other.

The method according to claim 1,
Wherein the flexible substrate is fixed to the support substrate with an epoxy-based or silicone-based adhesive.

The method according to claim 1,
And a barrier disposed around the first open region.

9. The method of claim 8,
Wherein the barrier includes a first barrier and a second barrier separated from each other, and the light emitting device is electrically connected to the first barrier and the second barrier, respectively.

10. The method of claim 9,
Wherein the light emitting element is bonded to the first barrier and the second barrier with wires, respectively, and the heights of the first barrier and the second barrier in the bonding region are lower than the height in the non-bonding region.

9. The method of claim 8,
Further comprising a region where a part of the supporting substrate is exposed in an edge region of the barrier, and a temperature measuring sensor is disposed in the exposed region.

The method according to claim 1,
Wherein the conductive layer is exposed in at least two regions in the noncontact region in which the connector connection portion is disposed.

The method according to claim 1,
Wherein the flexible substrate is linear or curved.

The method according to claim 1,
A plurality of light emitting devices are disposed in a first open region of the flexible substrate, and the plurality of light emitting devices are connected in parallel to each other.

The method according to claim 1,
Wherein the supporting substrate has a thickness of 0.6 mm to 5 mm.

The method according to claim 1,
Wherein the first insulating layer and the second insulating layer each have a thickness of 35 micrometers to 3 millimeters.

The method according to claim 1,
Wherein the conductive layer has a thickness of 35 micrometers to 350 micrometers.

The method according to claim 1,
Wherein the supporting substrate is disposed in the direction of the first insulating layer of the flexible circuit board, and the connector connecting portion is disposed in the direction of the second insulating layer of the flexible circuit board.

A first insulating layer, a second insulating layer, and a conductive layer disposed between the first insulating layer and the second insulating layer, wherein the first region includes a first open region and a second region that is spaced from the first region by a predetermined distance A flexible substrate including a second region;
A support substrate in contact with the flexible substrate in the first region;
A light emitting element in contact with the supporting substrate in the first open region; And
And a connector connecting portion in contact with the flexible substrate in the second region.

A heat dissipating unit;
A light emitting device comprising the light emitting device module according to any one of claims 1 to 19, wherein the supporting substrate of the light emitting module is in thermal contact with the heat dissipating part;
Reflective portion; And
A headlamp comprising a lens.