KR20140146354A - Semiconductor light emitting device and package - Google Patents

Abstract

A semiconductor light emitting device according to the embodiment of the present invention includes a heat sink and a semiconductor light emitting package which is attached on the heat sink. The semiconductor light emitting device package includes one or more light emitting devices to emit light and a heat radiation pad which includes a first surface on which one or more light emitting devices are mounted and a second surface which is opposite to the first surface and is bonded on the upper side of the heat sink.

Description

Technical Field [0001] The present invention relates to a semiconductor light emitting device and a semiconductor light emitting device package,

The present invention relates to a semiconductor light emitting device and a semiconductor light emitting device package.

Light emitting diodes (LEDs) are widely used as light sources because of their low power consumption and high brightness. In particular, recent light emitting devices have been employed as backlight devices for lighting devices and large liquid crystal displays (LCDs). Such a light emitting element is provided in the form of a package which can be easily mounted on various apparatuses such as a lighting apparatus. As the use of LEDs for illumination increases in various directions, the size of the package must be reduced for the freedom of lighting design for each application. In addition, the high heat dissipation performance is a package condition that is more importantly required in a field where a high output light emitting device such as a general lighting device and a large LCD backlight is required.

There is a need in the art for a new semiconductor light emitting device and a semiconductor light emitting device package in which the heat dissipation characteristics are improved and the size of the entire package is reduced by applying a small size heat sink.

A semiconductor light emitting device according to an embodiment of the present invention includes a heat sink and a semiconductor light emitting device package mounted on the heat sink, wherein the semiconductor light emitting device package includes at least one light emitting element for emitting light, And a heat radiating pad having a first surface on which at least one light emitting element is mounted and a second surface opposite to the first surface and joined to the upper surface of the heat sink.

In some embodiments of the present invention, the semiconductor light emitting device package includes at least one connection portion formed in at least a part of the first surface of the heat radiation pad, and the connection portion is electrically connected to the electrode of the at least one light emitting element .

In some embodiments of the present invention, the connection portion includes an insulating layer located at least in a partial region of the first surface of the heat radiation pad, and a conductive layer disposed on the insulating layer.

In some embodiments of the present invention, a portion of the insulating layer is provided as a support for a fixing member for fastening the semiconductor light emitting device package and the heat sink to each other.

In some embodiments of the present invention, the heat radiating pad is a heat radiating pad, the first surface is in direct contact with the light emitting element, and the second surface is in direct contact with the heat sink to transmit heat generated in the light emitting element to the heat sink do.

In some embodiments of the present invention, the heat radiating pad includes a reflective film provided on the first surface, and the reflective film reflects light emitted from the light emitting element.

A semiconductor light emitting device package according to an embodiment of the present invention includes at least one light emitting element for emitting light, a first surface on which the one or more light emitting elements are mounted, and a second surface parallel to the first surface, And a connection part electrically connected to the electrodes of the one or more light emitting devices, the connection pad being provided on the first surface of the heat dissipation pad. The heat dissipation pad may include a heat dissipation pad attached to a heat sink for emitting heat generated from the at least one light emitting device.

In some embodiments of the present invention, the connecting portion includes an insulating layer and a conductive layer provided on the insulating layer.

In some embodiments of the present invention, at least a portion of the insulating layer is provided as a support for a fixing member for fastening the heat radiating pad and the heat sink to each other.

In some embodiments of the present invention, at least a portion of the at least one light emitting element is in direct contact with the first surface of the heat spreading pad.

By attaching the light emitting device directly mounted on the heat dissipating pad to the heat sink without a conventional substrate structure such as a PCB, the process can be simplified and the heat dissipation property can be improved and the price competitiveness can be enhanced.

The various and advantageous advantages and effects of the present invention are not limited to the above description, and can be more easily understood in the course of describing a specific embodiment of the present invention.

1 is a perspective view schematically showing a semiconductor light emitting device according to an embodiment of the present invention.
2 is a plan view schematically showing a semiconductor light emitting device according to an embodiment of the present invention.
3 is a cross-sectional view taken along the line AA 'of the semiconductor light emitting device shown in FIG.
4 is a cross-sectional view schematically showing a semiconductor light emitting device according to an embodiment of the present invention.
5 is a cross-sectional view schematically showing a semiconductor light emitting device that may be included in a semiconductor light emitting device package according to an embodiment of the present invention.
6 is a cross-sectional view schematically showing a semiconductor light emitting device that may be included in a semiconductor light emitting device package according to an embodiment of the present invention.
7 is a cross-sectional view schematically showing a semiconductor light emitting device that may be included in a semiconductor light emitting device package according to an embodiment of the present invention.
8 is a cross-sectional view schematically showing a semiconductor light emitting device according to an embodiment of the present invention.
9 shows an example in which a semiconductor light emitting device according to an embodiment of the present invention is applied to a lighting device.
10 shows an example in which the semiconductor light emitting device according to the embodiment of the present invention is applied to a headlamp.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

The embodiments of the present invention may be modified into various other forms or various embodiments may be combined, and the scope of the present invention is not limited to the embodiments described below. Further, the embodiments of the present invention are provided to more fully explain the present invention to those skilled in the art. Accordingly, the shapes and sizes of the elements in the drawings may be exaggerated for clarity of description, and the elements denoted by the same reference numerals in the drawings are the same elements.

1 is a perspective view schematically showing a semiconductor light emitting device according to an embodiment of the present invention.

Referring to FIG. 1, a semiconductor light emitting device 100 according to an embodiment of the present invention may include a semiconductor light emitting device package 200 and a heat sink 300. The semiconductor light emitting device package 200 may include one or more light emitting devices 210 for generating light and a heat dissipation pad 220 on which the light emitting devices 210 are mounted. In the present embodiment, the light emitting device 210 included in the semiconductor light emitting device package 200 may include only a light emitting diode chip, or may be provided in the form of a package including a light emitting diode chip. For example, Scale Package (CSP), or Wafer Level Package (WLP).

The light emitting device 210 may include a light emitting diode (LED) chip, and may include a first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer. The first conductive type semiconductor layer may be formed on the substrate, and the substrate may include a substrate body portion and a wavelength conversion layer. Various embodiments of the light emitting device 210 will be described later with reference to Figs. 5 to 7.

The terms 'phase', 'upper', 'upper', 'lower', 'lower', 'lower', 'side', etc. used in the specification are based on the drawings, And the direction in which the package is placed.

In the present embodiment, when the plurality of light emitting devices 210 are included in the semiconductor light emitting device package 200, the plurality of light emitting devices 210 may be mounted on the heat dissipating pad 220 in an array form. That is, a PCB substrate on which a plurality of light emitting devices 210 are mounted on a PCB substrate or the like and a plurality of light emitting devices 210 are mounted is not attached to the heat sink 300 using the heat radiation pads 220, The plurality of light emitting devices 210 are directly mounted on the heat dissipating pad 220 without the PCB substrate.

Accordingly, since the heat generated by the plurality of light emitting devices 210 is directly transmitted to the heat dissipation pad 220 without passing through the PCB substrate, the heat dissipation efficiency of the entire semiconductor light emitting device 100 can be improved. For example, the plurality of light emitting devices 210 may be mounted on the first surface of the heat dissipating pad 220, and the first surface of the heat dissipating pad 220 may include a plurality of light emitting devices 210 for applying a driving signal to the plurality of light emitting devices 210 Electrode pattern.

The heat dissipation pad 220 may have a structure for increasing the luminous efficiency of light emitted from the plurality of light emitting devices 210 mounted on the first surface. In FIG. 1, Of barrier ribs 240 are formed. A reflection film, a reflection coating, and the like are provided on the inner peripheral surface of the barrier rib 240 to improve the luminous efficiency of the plurality of light emitting devices 210. The heat dissipation pad 220 may be provided with a fastening part 230 for inserting a fixing member for fastening the heat dissipation pad 220 and the heat sink 300 to each other.

The heat dissipation pad 220 may include a methyl-based silicone, and the plurality of light emitting devices 210 may be attached to the heat dissipation pad 220 by the viscosity of the methyl-based silicon itself. For example, a plurality of light emitting devices 210 may be bonded to the heat dissipating pad 220 while the heat dissipating pad 220 including the methyl-based silicone is semi-cured, and a plurality of light emitting devices 210 may be bonded to the heat dissipating pad 220, The plurality of light emitting devices 210 can be mounted on the heat dissipating pad 220 without using a die bonding paste by curing the heat dissipating pad 220 in a hot state.

The circuit pattern electrically connected to the electrode of the light emitting element 210 may be formed on the heat dissipating pad 220 in advance in the case where the flip chip type light emitting element 210 is mounted on the heat dissipating pad 220, A method of bonding the light emitting device 210 to the semi-cured heat radiation pad 220 and curing the heat radiation pad 220 can not be applied. In the case where the flip chip type light emitting device 210 is included in the semiconductor light emitting device package 200, a circuit pattern is preliminarily formed of copper or the like on the cured heat emitting pad 220, The light emitting element 210 can be mounted on the heat dissipation pad 220 by electrically connecting the electrode and the circuit pattern by a solder bump method using Au-Sn or the like.

The heat-radiating pad 220 may further include a material in powder form to enhance heat conductivity to the heat sink 300, in addition to methyl-based silicone. The powder material that may be added to the heat dissipation pad 220 to enhance the thermal conductivity may be nano powder or carbon powder.

2 is a plan view schematically showing a semiconductor light emitting device according to an embodiment of the present invention.

Referring to FIG. 2, the semiconductor light emitting device 400 according to the present embodiment may include a light emitting device 510 and a heat dissipation pad 520 on which the light emitting device 510 is mounted. A heat sink for emitting heat generated by the light emitting device 510 may be attached to a lower portion of the heat dissipating pad 520. The light emitting device 510 and the heat radiating pad 520 may be included in the semiconductor light emitting device package 500 together with other components that may be selectively added.

The first surface 520a of the heat dissipation pad 520 may be provided with a connection portion 515 electrically connected to the light emitting device 510. [ The connection unit 515 may be electrically connected to the electrode of the light emitting device 510 through the bonding wire 513 and may transmit an external driving signal to the electrode of the light emitting device 510. The configuration of the connection unit 515 will be described later with reference to Fig.

2, the light emitting device 510 may be disposed in the partition 540 provided on the first surface 520a of the heat radiation pad 520. [ 2, the barrier rib 540 may have various shapes such as an ellipse and a quadrangle in addition to the circular shape. A reflective film or a reflective coating is formed on the inner peripheral surface of the barrier rib 540, 510) can be increased.

In addition, a fastening portion 530 may be provided on at least a part of the first surface 520a of the heat radiation pad 520. [ Although it is assumed in FIG. 2 that the two fastening portions 530 are disposed in the diagonal direction of the rectangular plane of the heat radiating pad 520, the present invention is not limited thereto, and three or more fastening portions 530 may be provided . The semiconductor light emitting device 400 can be connected to and fixed to the heat sink by using a fixing member coupled to the coupling part 530. When a screw is used as a fixing member, And a part of the area of the first portion 515 may extend to the fastening portion 530.

On the other hand, an encapsulating material may be provided on the light emitting element 510, the bonding wire 513, and the connection part 515. The encapsulant may have a light transmissive material that transmits light output from the light emitting device 510 to the outside and may serve as a lens that emits light output from the light emitting device 510 to the outside.

A reflective film for increasing the luminous efficiency of the light emitting device 510 may be provided on the first surface 520a of the heat dissipation pad 520 on which the light emitting device 510 is mounted. The reflective film may be provided in the form of attaching a film having a high reflectance, or may be provided by coating a material having high reflectance. In another embodiment, a separate reflective film may be provided on the first surface 520a instead of the heat radiation pad 520 as a material capable of increasing the reflectance.

In Fig. 2, the light emitting element 510 can be mounted on the heat dissipating pad 520 in a manner similar to that shown in Fig. 2, it is assumed that a mounting method for electrically transmitting a signal to the light emitting device 510 using a bonding wire 513 is adopted. 2, the light emitting device 510 may be directly bonded to the heat dissipation pad 520 in a semi-cured state and the heat dissipation pad 520 may be cured to bond the light emitting device 510 to the heat dissipation pad 520. [ Can be mounted. The connection portion 515 may be formed on the heat radiation pad 520 before or after the light emitting device 510 is mounted.

3 is a cross-sectional view taken along the line A-A 'of the semiconductor light emitting device shown in FIG.

3, the semiconductor light emitting device 400 according to the present embodiment includes a light emitting element 510, a heat radiating pad 520 on which the light emitting element 510 is mounted, and a heat sink 600 attached to the heat radiating pad 520 ). 3, the light emitting device 510 is mounted on the first surface 520a of the heat radiating pad 520 without being mounted on a separate PCB or the like, and the second surface 520b of the heat radiating pad 520 Is directly attached to the heat sink 600. [ Therefore, heat generated in the light emitting device 510 is directly transmitted to the heat sink 600 through the heat radiation pad 520 without passing through a medium such as a PCB substrate, and when the light emitting device 510 is mounted on the PCB substrate The heat dissipation efficiency can be improved.

The terms 'phase', 'top', 'top', 'bottom', 'bottom', 'bottom', 'side', etc. used throughout this specification are to be construed as separate adhesive or adhesive layers, Means a form in which two components are directly attached without a layer interposed between the two components. For example, as shown in FIG. 3, the heat radiating pad 520 and the heat sink 600 are directly contacted and attached to the second surface 520b of the heat radiating pad 520 without an adhesive agent or an adhesive layer. The heat radiating pad 520 and the light emitting element 510 may also be mounted directly in contact with the first surface 520a of the heat radiating pad 520. [

That is, in the present embodiment, the light emitting element 510 is directly mounted on the heat radiating pad 520, not on the PCB substrate. Accordingly, heat generated in the light emitting device 510 is transmitted to the heat sink 600 through the heat radiation pad 520 without passing through the PCB substrate having a relatively large heat resistance value. Accordingly, since the heat generated from the light emitting device 510 can be efficiently exported, the heat sink 600 having a smaller size can be used under the same conditions, thereby reducing the overall package size.

Meanwhile, the light emitting device 510 may include a plurality of electrodes 511, and each of the plurality of electrodes 511 may be connected to the first conductive semiconductor layer and the second conductive semiconductor layer. That is, the light emitting device 510 can be operated by applying an electric signal to each of the plurality of electrodes 511. The plurality of electrodes 511 are electrically connected to the conductive layer (not shown) of the connection portion 515 515b.

The connection portion 515 may include an insulating layer 515a provided below the conductive layer 515b and a photo solder resist layer PSR 515c provided on the conductive layer 515b. For example, the insulating layer 515a may include a material such as FR-4, and the conductive layer 515b may include a conductive metal material such as Cu, Ag, Au, and the like. The conductive layer 515b may be connected to the electrode 511 of the light emitting element 510 through a bonding wire 513 as shown in FIG.

4 is a cross-sectional view schematically showing a semiconductor light emitting device according to an embodiment of the present invention.

Referring to FIG. 4, the semiconductor light emitting device according to the present embodiment includes a semiconductor light emitting device package 800 and a heat sink 900. The semiconductor light emitting device package 800 includes a plurality of light emitting devices 810 and a plurality of light emitting devices 810 directly mounted on the first surface 820a and a second surface 820b parallel to the first surface 820a And a heat-radiating pad 820 provided on a surface that contacts the heat sink 900. The plurality of light emitting devices 810 are connected to each other in an array form and connected to the connection unit 815 through a bonding wire 813 to receive a driving signal required for light emission.

The heat sink 900 receives heat generated from the plurality of light emitting devices 810 through the heat dissipation pad 820 and discharges the heat to the outside. The thermal resistance of the entire semiconductor light emitting device package 800 including the heat dissipation pad 820 and the plurality of light emitting devices 810, the bonding wires 813, and the connection portions 815 is greater than the thermal resistance of the plurality of light emitting devices 810. [ The bonding wire 813 and the connecting portion 815 and the like are added to the thermal resistance value of the component mounted on the first surface 820a of the heat radiation pad 820 plus the thermal resistance value of the heat radiation pad 820 .

In the general semiconductor light emitting device package 800, there may be a separate PCB substrate attached to the first surface 820a of the heat radiation pad 820, and a plurality of light emitting devices 810, bonding wires 813, and a connecting portion 815 are provided. Therefore, the thermal resistance value of the PCB substrate affects the thermal resistance value of the semiconductor light emitting device package 800 as a whole. The thermal resistance value of the PCB substrate may be 0.4 K / W or more, which is larger than the thermal resistance values of the plurality of light emitting devices 810 and the heat radiation pads 820.

For example, a light emitting device 810 having a thermal resistance value of 0.05 K / W is mounted on an aluminum (Al) substrate having a thermal resistance value of 0.463 K / W by using a DB PASTE of 0.045 K / W, Assuming that the package is attached to the heat sink 300 by attaching the heat radiation pad 820 having a thermal resistance value of K / W, the thermal resistance value of the entire package is 0.658 K / W. On the other hand, when the light emitting element 810 is directly mounted on the heat radiating pad 820 except for the Al substrate in the same configuration, the Al substrate is omitted and the thermal resistance value of the package including the heat radiating pad 820 is 0.195 K / W 70%. Therefore, the heat dissipation performance can be improved by the configuration of the present embodiment in which the light emitting element 810 is directly mounted on the heat dissipating pad 820. [

As a result, heat generated in the semiconductor light emitting device package 800 is difficult to be transmitted to the heat sink 900 through the heat radiation pad 820 due to the PCB substrate having a relatively large thermal resistance value, . In addition, since a heat sink 900 of a large size is applied to increase the heat dissipation performance, the price increases and it may be difficult to apply to various products.

The PCB substrate is omitted in the semiconductor light emitting device package 800 and a plurality of light emitting devices 810 and bonding wires 813 are directly connected to the first surface 820a of the heat radiating pad 820, (815). Accordingly, the PCB substrate having a high thermal resistance can be removed from the semiconductor light emitting device package 800, and heat generated from the plurality of light emitting devices 810 can be transmitted only through the heat sink pad 820 having low heat resistance, Is directly transmitted to the heat sink 900, the heat radiation performance can be enhanced. In addition, since the price competitiveness is improved and the heat sink 900 having the small size can obtain the same or better heat radiation performance as the existing product, it is easy to realize the desired heat radiation performance with the small size heat sink 900 The product can be miniaturized.

4, the light emitting element 810 may be mounted on the heat dissipating pad 820 in a manner similar to that described with reference to FIG. In FIG. 4, the light emitting device 810 receives a signal necessary for operation through a bonding wire 813. 4, the light emitting device 810 is directly bonded to the heat dissipation pad 820 in a semi-cured state without any additional paste, and the heat dissipation pad 820 is cured to form the heat dissipation pad 820 The light emitting element 810 can be mounted.

5 to 7 are side cross-sectional views schematically showing an example of a light emitting element as an LED chip.

5, the light emitting device 1000 may include a light emitting stack L formed on a growth substrate 1001. In this case, The light emitting stacked body L may include a first conductive semiconductor layer 1004, an active layer 1005, and a second conductive semiconductor layer 1006.

An ohmic contact layer 1008 may be formed on the second conductive semiconductor layer 1006. The first conductive semiconductor layer 1004 and the ohmic contact layer 1008 may have first and second Two electrodes 1009a and 1009b may be formed.

Hereinafter, the major components of the light emitting device 1000 will be described in more detail.

[Board]

The substrate constituting the light emitting element is a substrate for growth for epitaxial growth. As the substrate 1001, an insulating, conductive, or semiconductor substrate may be used if necessary. It may be, for example, sapphire, SiC, Si, MgAl ₂ O _4, MgO, LiAlO _2, LiGaO _2, GaN. A GaN substrate, which is a homogeneous substrate, is preferable for epitaxial growth of a GaN material, but a GaN substrate has a problem of high production cost due to its difficulty in manufacturing.

Sapphire and silicon carbide (SiC) substrates are mainly used as the different substrates, and sapphire substrates are used more than silicon carbide substrates, which are expensive. When using a heterogeneous substrate, defects such as dislocation are increased due to the difference in lattice constant between the substrate material and the thin film material. Also, due to the difference in the thermal expansion coefficient between the substrate material and the thin film material, warping occurs at a temperature change, and warping causes a crack in the thin film. This problem may be reduced by using the buffer layer 1002 between the substrate 1001 and the light emitting laminate L which is GaN-based.

The substrate 1001 may be completely or partially removed or patterned in a chip manufacturing process to improve the optical or electrical characteristics of the LED chip before or after the growth of the light emitting stacked body L. [

For example, in the case of a sapphire substrate, the substrate can be separated by irradiating the laser to the interface with the semiconductor layer through the substrate, and the silicon or silicon carbide substrate can be removed by a method such as polishing / etching.

In order to improve the light efficiency of the LED chip on the opposite side of the growth substrate, the support substrate may be bonded by using a reflective metal, or the reflection structure may be inserted in the middle of the bonding layer can do.

Substrate patterning improves the light extraction efficiency by forming irregularities or slopes before or after growth of the light emitting stack on the main surface (front surface or both sides) or the side surface of the substrate. The size of the pattern can be selected from the range of 5 nm to 500 μm and it is possible to make a structure for improving the light extraction efficiency with a rule or an irregular pattern. Various shapes such as a shape, a column, a mountain, a hemisphere, and a polygon can be adopted.

In the case of the sapphire substrate, the lattice constants of the hexagonal-rhombo-cubic (Hexa-Rhombo R3c) symmetry are 13.001 Å and 4.758 Å in the c-axis and the a- , R (1102), and the like. In this case, the C-plane is relatively easy to grow the nitride film, and is stable at high temperature, and thus is mainly used as a substrate for nitride growth.

As another material of the substrate 1001, an Si substrate can be exemplified, which is more suitable for large-scale curing and relatively low in price, and thus, mass productivity can be improved. There is a need for a technique for suppressing the occurrence of crystal defects due to the difference in lattice constant between the Si substrate having the (111) plane as the substrate surface and the lattice constant difference of about 17% with GaN. Further, the difference in thermal expansion coefficient between silicon and GaN is about 56%, and a technique for suppressing the wafer warping caused by the difference in thermal expansion rate is needed. Wafer warpage can cause cracking of the GaN thin film, and process control is difficult, which can cause problems such as a large scattering of the emission wavelength in the same wafer.

Since the external quantum efficiency of the light emitting device is lowered by absorbing the light generated from the GaN-based semiconductor, the silicon (Si) substrate may be removed, if necessary, and Si, Ge, SiAl, Or the like is further formed and used.

[Buffer layer]

When a GaN thin film is grown on a different substrate such as the Si substrate, the dislocation density increases due to the lattice constant mismatch between the substrate material and the thin film material, and cracks and warpage Lt; / RTI > The buffer layer 1002 is disposed between the substrate 1001 and the light emitting stacked body L for the purpose of preventing dislocation and cracking of the light emitting stacked body L. [ The buffer layer 1002 also functions to reduce the wavelength dispersion of the wafer by controlling the degree of warping of the substrate during the growth of the active layer.

The buffer layer 1002 may be made of Al _x In _y Ga _{1 -x- y} N (0 = x = 1, 0 = y = 1), in particular GaN, AlN, AlGaN, InGaN or InGaNAlN. ZrB ₂ , HfB ₂ , ZrN, HfN, TiN and the like can also be used. Further, a plurality of layers may be combined, or the composition may be gradually changed.

Since the Si substrate has a large difference in thermal expansion coefficient from that of GaN, the GaN thin film is grown at a high temperature when the GaN thin film is grown on the silicon substrate, and then the tensile stress is applied to the GaN thin film due to the difference in thermal expansion coefficient between the substrate and the thin film And cracks are likely to occur. Tensile stress is compensated by using a method to prevent cracks by growing the thin film so that the thin film undergoes compressive stress during growth.

Silicon (Si) has a high probability of occurrence of defects due to a difference in lattice constant with GaN. In case of using Si substrate, a complex structure buffer layer is used because it is necessary not only to control defects but also to control stress to suppress warpage.

For example, AlN is formed on the substrate 1001 first. It is advisable to use a material that does not contain Ga to prevent Si and Ga reactions. AlN as well as materials such as SiC can be used. Using Al source and N source, 400 ~ 1300? Lt; / RTI > If necessary, an AlGaN intermediate layer for controlling the stress in the middle of GaN can be inserted between the plurality of AlN layers.

[Luminescent laminate]

More specifically, the first and second conductivity-type semiconductor layers 1004 and 1006 are made of semiconductors doped with n-type and p-type impurities, respectively, .

However, the present invention is not limited thereto, and conversely, it may be a p-type and an n-type semiconductor layer, respectively. For example, the first and second conductive semiconductor layers 1004 and 1006 may be formed of a Group III nitride semiconductor, for example, Al _x In _y Ga _{1 -x- y} N (0 = x = 1, 0 = 0 = x + y = 1). Of course, the present invention is not limited to this, and materials such as AlGaInP series semiconductor and AlGaAs series semiconductor may be used.

Meanwhile, the first and second conductivity type semiconductor layers 1004 and 1006 may have a single-layer structure, but may have a multi-layer structure having different compositions and thicknesses as needed. For example, the first and second conductivity type semiconductor layers 1004 and 1006 may have a carrier injection layer capable of improving the injection efficiency of electrons and holes, respectively, and may have various superlattice structures You may.

The first conductive semiconductor layer 1004 may further include a current diffusion layer (not shown) at a portion adjacent to the active layer 1005. The current diffusion layer may have a different composition or a structure in which a plurality of In _x Al _y Ga _{1 -x- y} N layers having different impurity contents are repeatedly laminated or a layer of an insulating material may be partially formed.

The second conductive semiconductor layer 1006 may further include an electron blocking layer (not shown) at a portion adjacent to the active layer 1005. The electron blocking layer is a structure or Al _y Ga ₁ laminating the In _x Al _y Ga _1-xy N of the plurality of different composition _- the band gap than can have at least one layer layer consisting of _y N and the active layer 1005 This prevents the electrons from falling into the second conductive type (p-type) semiconductor layer 1006.

The light emitting laminate L may be an MOCVD apparatus and may be fabricated by using an organic metal compound gas such as trimethyl gallium (TMG), trimethyl aluminum (TMA), or the like as a reaction gas in a reaction vessel provided with a growth substrate 1001, And a nitrogen-containing gas (ammonia (NH3) or the like) is supplied to the substrate, the temperature of the substrate is maintained at a high temperature of 900 to 1100 占 and a gallium nitride compound semiconductor is grown on the substrate, And a gallium nitride compound semiconductor is laminated in an undoped, n-type, or p-type. As the n-type impurity, Si is well known. As the p-type impurity, Zn, Cd, Be, Mg, Ca, Ba, etc. are mainly used.

The active layer 1005 disposed between the first and second conductivity type semiconductor layers 1004 and 1006 may be a multiple quantum well (MQW) structure in which a quantum well layer and a quantum barrier layer are alternately stacked, , A GaN / InGaN structure may be used, but a single quantum well (SQW) structure may also be used.

[The ohmic contact layer and the first and second electrodes]

The ohmic contact layer 1008 may have a relatively high impurity concentration to lower the ohmic contact resistance, thereby lowering the operating voltage of the device and improving the device characteristics. The ohmic contact layer 1008 may be composed of GaN, InGaN, ZnO, or a graphene layer.

The first and second electrodes 1009a and 1009b may include a material such as Ag, Ni, Al, Rh, Pd, Ir, Ru, Mg, Zn, , Ni / Al, Zn / Al, Pd / Ag, Pd / Al, Ir / Ag. Or two or more layers such as Ir / Au, Pt / Ag, Pt / Al, and Ni / Ag / Pt.

The LED chip shown in FIG. 5 includes, for example, a structure in which the first and second electrodes face the same surface as the light extracting surface, a flip chip structure in which the first and second electrodes are opposite to the light extracting surface, The vertical structure formed on the opposite surface, the structure for increasing the efficiency of current dispersion and the heat dissipation efficiency, and the vertical and horizontal structure employing the electrode structure by forming multiple vias on the chip.

≪ Light emitting device - Example 2 &

In manufacturing a large-area light emitting device for high output, there may be a light emitting diode chip shown in FIG. 6 as a structure for efficiency of current dispersion and heat dissipation efficiency.

6, the light emitting diode chip 1100 includes a first conductive semiconductor layer 1104, an active layer 1105, a second conductive semiconductor layer 1106, a second electrode layer 1107, an insulating layer 1102, a first electrode layer 1108, and a substrate 1101. The first electrode layer 1108 is electrically insulated from the second conductivity type semiconductor layer 1106 and the active layer 1105 to be electrically connected to the first conductivity type semiconductor layer 1104, And at least one contact hole (H) extending from one surface to at least a partial region of the first conductive semiconductor layer (1104). The first electrode layer 1108 is not an essential component in the present embodiment.

The contact hole H is formed in the first conductive semiconductor layer 1104 through the second electrode layer 1107, the second conductive semiconductor layer 1106 and the active layer 1105 from the interface of the first electrode layer 1108, . At least to the interface between the active layer 1105 and the first conductivity type semiconductor layer 1104 and preferably to a portion of the first conductivity type semiconductor layer 1104. [ However, since the contact hole H is for electrical connection and current dispersion of the first conductivity type semiconductor layer 1104, the contact hole H is formed in contact with the first conductivity type semiconductor layer 1104, 1104, < / RTI >

The second electrode layer 1107 connected to the second conductivity type semiconductor layer 1106 is formed of Ag, Ni, Al, Rh, Pd, or the like in consideration of the light reflection function, the second conductivity type semiconductor layer 1106, , Ir, Ru, Mg, Zn, Pt, and Au, and may be sputtered or deposited.

The contact hole H has a shape penetrating the second electrode layer 1107, the second conductivity type semiconductor layer 1106 and the active layer 1105 to be connected to the first conductivity type semiconductor layer 1104. Such a contact hole H can be performed using an etching process, for example, ICP-RIE.

An insulating layer 1102 is formed to cover a side wall of the contact hole H and a lower surface of the second electrode layer 1107. In this case, at least a part of the first conductivity type semiconductor layer 1104 may be exposed by the contact hole H. [ The insulating layer 1102 may be formed by depositing an insulating material such as SiO2, SiOxNy, or SixNy.

A first electrode layer 1108 including a conductive via filled with a conductive material is formed in the contact hole H. Subsequently, a substrate 1101 is formed under the first electrode layer 1108. In this structure, the substrate 1101 may be electrically connected by the conductive vias connected to the first conductive type semiconductor layer 1104.

Material that the substrate 1101 includes any one of, but are not limited to Au, Ni, Al, Cu, W, Si, Se, GaAs, SiAl, Ge, Sic, AlN, Al 2 O 3, GaN, AlGaN And may be formed by a process such as plating, sputtering, vapor deposition or adhesion.

The number, shape, pitch, contact area of the first and second conductivity type semiconductor layers 1104 and 1106, and the like may be appropriately adjusted to reduce the contact resistance of the contact hole H, The current flow can be improved. At this time, the second electrode layer 1107 may include at least one exposed region E, that is, a region where a part of the interface that contacts the second conductive type semiconductor layer 1106 is exposed. And an electrode pad portion 1109 for connecting an external power source to the second electrode layer 1107 may be provided on the exposed region E. [

6, the LED chip 1100 includes first and second conductive semiconductor layers 1104 and 1102 having first and second major surfaces facing each other and providing the first and second main surfaces, respectively, And a contact hole H connected to one region of the first conductive type semiconductor layer 1104 from the second main surface through the active layer 1105 and a second conductive type semiconductor layer 1104 interposed between the second main surface and the active layer 1105, A first electrode layer 1108 formed on a second main surface of the light emitting structure and connected to one region of the first conductive semiconductor layer 1104 through the contact hole H, And a second electrode layer 1107 formed on the second conductive semiconductor layer 1106 and connected to the second conductive semiconductor layer 1106. Here, one of the first and second electrode layers 1108 and 1107 may have a structure that is drawn out laterally of the light emitting structure.

7 is a cross-sectional view schematically showing a semiconductor light emitting device that may be included in a semiconductor light emitting device package according to an embodiment of the present invention.

The semiconductor light emitting device 1200 shown in FIG. 7 includes a semiconductor stacked body 1210 formed on a substrate 1201. The semiconductor layered structure 1210 may include a first conductive type semiconductor layer 1212, an active layer 1214, and a second conductive type semiconductor layer 1216.

The semiconductor light emitting device 1200 includes first and second electrodes 1222 and 1224 connected to the first and second conductivity type semiconductor layers 1212 and 1216, respectively. The first electrode 1222 is connected to the conductive via 1222a and the conductive via 1222a which are connected to the first conductive type semiconductor layer 1212 through the second conductive type semiconductor layer 1216 and the active layer 1214 Electrode extension portion 1222b. The conductive vias 1222a may be surrounded by the insulating layer 1221 and electrically separated from the active layer 1214 and the second conductivity type semiconductor layer 1216. [ The conductive vias 1222a may be disposed in the area where the semiconductor stacked body 1210 is etched. The number, shape, pitch, or contact area between the conductive via 1212a and the first conductive type semiconductor layer 1212 can be appropriately designed so that the contact resistance is lowered. Further, the conductive vias 1222a are arranged in rows and columns on the semiconductor stacked body 1210, thereby improving current flow. The second electrode 1224 may include an ohmic contact layer 1224a and an electrode extension 1224b on the second conductive semiconductor layer 1216. [

8 is a cross-sectional view schematically showing a semiconductor light emitting device according to an embodiment of the present invention.

8, an electrode 2111 provided in a flip-chip type light emitting device 2110 is connected to a conductive layer of a connection portion 2115 on a heat radiation pad 2100 through a solder bump 2117 do. The connection portion 2115 may include an insulating layer and a photo solder resist layer in addition to the conductive layer in a region not connected to the solder bumps 2117. [ The insulating layer of the connection portion 2115 may include FR-4 or the like and may be used as a support for a fixing member connecting the heat radiation pad 2100 and the heat sink 3000 to each other.

The light emitting device 2110 may include first and second conductive semiconductor layers and an active layer provided between the first and second conductive semiconductor layers. Light emitted by the combination of electrons and holes in the active layer in the light emitting device 2110 shown in Fig. 8 is emitted to the upper side where the electrode 2111 is not provided. Therefore, the luminous efficiency can be improved as compared with the embodiment shown in Figs. 8, a reflective film for improving the luminous efficiency may be provided on the first surface 2120a of the heat-radiating pad 2100, or a material capable of increasing the reflectance may be provided in the heat-radiating pad 2100 Can be added.

In the embodiment of Fig. 8, a connection portion 2115 is provided on the heat radiation pad 2100 to mount the light emitting element 2110. [ Therefore, instead of directly bonding the light emitting element 2110 to the heat radiation pad 2100 in a semi-cured state without bonding the die bonding paste, a connecting portion 2115 and other necessary circuit patterns (not shown) are formed on the cured heat radiation pad 2100, And the light emitting device 2110 can be mounted thereon with a solder bump 2117 or the like.

9 shows an example in which a semiconductor light emitting device according to an embodiment of the present invention is applied to a lighting device.

9, the illumination device 4000 is illustrated as a bulb-type lamp, and includes a light emitting module 4004, a driver 4006, and an external connection 4008. [ In addition, an external structure such as the housing 4007 and the cover part 4001 may be additionally included. The light emitting module 4004 may have the structure of the above-described semiconductor light emitting device package or a similar structure. For example, the light emitting module 4004 may include a light source 4002 and a heat radiation pad 4003 on which the light source 4002 is mounted. For example, a light emitting element similar to the one shown in FIG. 3 may be included in the light source 4002, and the electrode of the light emitting element may be connected to the electrode pattern of the heat dissipating pad 4003. In the present embodiment, one light source 4002 is illustrated as being mounted on the heat dissipation pad 4003, but a plurality of light sources 4002 may be provided as necessary.

The heat generated from the light source 4002 can be emitted to the outside through the heat emitting portion and the heat sink 4005 for directly contacting the light emitting module 4004 and improving the heat radiation effect can be mounted on the illuminating device 4000 ). The cover part 4001 is mounted on the light emitting module 4004 and may have a convex lens shape. The driving unit 4006 may be mounted on the housing 4007 and connected to an external connection unit 4008 such as a socket structure to receive power from an external power source. The driving unit 4006 converts the current to a suitable current source capable of driving the semiconductor light emitting device 4002 of the light emitting module 4004 and provides the current. For example, such a driver 4006 may be composed of an AC-DC converter or a rectifying circuit component or the like.

Further, although not shown in the drawings, the illumination device 4000 may further include a communication module.

10 shows an example in which the semiconductor light emitting device according to the embodiment of the present invention is applied to a headlamp.

10, a head lamp 5000 used as a vehicle light or the like includes a light source 5001, a reflecting portion 5010, and a lens cover portion 5013. The lens cover portion 5013 includes a hollow guide A lens 5012, and a lens 5011. [ The light source 5001 may include at least one of the above-described semiconductor light emitting devices. The light source 5001 may be mounted directly on the upper surface of the heat radiation pad 5002 without a separate PCB substrate and the heat sink 5003 may be attached to the lower surface of the heat radiation pad 5002, The heat generated in the heat exchanger can be released to the outside.

The head lamp 5000 may further include a heat dissipating unit 5005 that externally dissipates the heat generated by the light source 5001. The heat dissipating unit 5005 may include a heat sink 5003, (5004). The head lamp 5000 may further include a housing 5009 for fixing and supporting the heat dissipating unit 5005 and the reflecting unit 5010. The housing 5009 may include a heat dissipating unit 5005 And a center hole 5008 for mounting.

The housing 5009 may include a front hole 5007 that is integrally connected to the one surface and bent at a right angle to fix the reflecting portion 5010 so as to be positioned on the upper side of the light source 5001. The reflector 5010 is fixed to the housing 5009 such that the front of the reflector 5010 corresponds to the front hole 5007 and the light reflected through the reflector 5010 Can be emitted to the outside through the front hole 5007.

The present invention is not limited to the above-described embodiment and the accompanying drawings, but is intended to be limited by the appended claims. It will be apparent to those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. something to do.

100, 400: semiconductor light emitting device
200, 500, 800: semiconductor light emitting device package
210, 510, 810: Light emitting element
220, 520, 820: heat radiating pad
520a, 820a: a first surface of the heat radiation pad
520b, 820b: a second surface of the heat radiation pad
300, 600, 900: Heat sink

Claims (10)

Heat sink; And
A semiconductor light emitting device package mounted on the heat sink; Lt; / RTI >
The semiconductor light emitting device package includes at least one light emitting element for emitting light, a first surface on which the at least one light emitting element is mounted, and a second surface opposite to the first surface and bonded to the upper surface of the heat sink A semiconductor light emitting device comprising a heat dissipation pad.
The method according to claim 1,
Wherein the semiconductor light emitting device includes at least one connection portion formed in at least a portion of a first surface of the heat radiation pad,
Wherein the connection portion is electrically connected to the electrode of the at least one light emitting element.
3. The method of claim 2,
Wherein the connection portion includes an insulating layer located at least in a region of the first surface of the heat radiation pad, and a conductive layer located on the insulating layer.
The method of claim 3,
Wherein a portion of the insulating layer is provided as a support for a fixing member for fastening the semiconductor light emitting device package and the heat sink to each other.
The method according to claim 1,
Wherein the heat radiation pad directly contacts the first surface with the light emitting element and the second surface directly contacts the heat sink to transfer heat generated in the light emitting element to the heat sink.
The method according to claim 1,
Wherein the heat dissipation pad includes a reflective film provided on the first surface,
Wherein the reflective film reflects light emitted from the light emitting device.
At least one light emitting element emitting light;
A heat radiating pad having a first surface on which the at least one light emitting element is mounted and a second surface parallel to the first surface, the second surface being attached to a heat sink that emits heat generated in the at least one light emitting element; And
A connection portion provided on a first surface of the heat dissipation pad and electrically connected to the electrodes of the at least one light emitting element; And the semiconductor light emitting device package.
8. The method of claim 7,
Wherein the connection portion includes an insulating layer, and a conductive layer provided on the insulating layer.
9. The method of claim 8,
Wherein at least a portion of the insulating layer is provided as a support for a fixing member for fastening the heat radiation pad and the heat sink to each other.
8. The method of claim 7,
And at least a part of the at least one light emitting element is in direct contact with the first surface of the heat radiating pad.

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