KR20140111536A - A heating element and LED device using that - Google Patents

Abstract

The present invention relates to a heating element and an LED device using the same. The heating element of the present invention provides an excellent dynamic heat dissipation effect, can be easily applied to a site during manufacture of the heating element, provides excellent reliability and economy of a product, and can improve light emitting efficiency of an LED device and long lifetime greatly.

Description

[0001] The present invention relates to a heat generating element,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat dissipating member capable of quickly and effectively emitting heat generated from an LED element such as an LED illumination and parts of an electronic or electric product to the outside.

LED lighting is expected to replace traditional lighting in the future in terms of environment friendliness, longevity and energy saving. It has been used as a simple display element in electric, electronic, and communication fields, , Monitors and other LED BLUs to replace the light source is expanding the market. In addition, it is gradually expanding its scope to general lighting areas such as indoor lighting, outdoor lighting and industrial lighting. LED industry is developing as an overall convergence technology utilizing IT, BT, NT, ET This is the expected industry.

Currently, the LED market is expanding exponentially. In 2007, the global LED market grew by 13.7% year-on-year, surpassing $ 60 billion, and the annual average compound growth rate of the global LED market by 10% This is expected. Korea accounts for about 8.3% of the global market, and domestic LED lighting is about W541.2bn in 2007, which is steadily growing at a CAGR of 20%.

However, the LEDs generate a lot of heat due to their characteristics, and if the heat is not appropriately discharged to the outside, there is a problem that the life of the LED is greatly shortened. In order to solve this problem, various heat-dissipating materials are used. However, no breakthrough structure or materials have been developed yet, and even in the case of heat-dissipating materials having some effects, there are many restrictions on price and use conditions for commercial products.

As shown in FIG. 1, it is not an exaggeration to say that about 85% of the total energy is generated by heat, and the whole of the heat is the heat of conduction and the heat of the heat must be emitted. As the heat dissipation increases the resistance, decreases the voltage, and decreases the intensity of light, it is difficult to enlarge the LED and increase the output power. The conventional LED heat dissipation system has a great effect on the heat dissipation effect which is a thermal disadvantage In addition, there is an urgent need to develop new LED heat dissipation technology that can have strong competitiveness in terms of reliability and economy of products.

Accordingly, the present inventors intend to provide a novel heat radiator to be introduced into an LED heat dissipation system, and to provide an LED device using the same.

According to an aspect of the present invention, there is provided a heat dissipator including: a graphene-containing layer; And a copper (Cu) -containing layer.

As an embodiment of the present invention, the heat radiator of the present invention may further include a layer containing a zinc oxide (ZnO) structure.

In another embodiment of the present invention, a graphene-containing layer is laminated on one side or both sides of the copper-containing layer, and the copper-containing layer has an average thickness of 0.001 mm to 0.5 mm.

In another embodiment of the present invention, the copper-containing layer and the graphen-containing layer are alternately laminated to form one layer, and the one layer is alternately laminated alternately.

In another embodiment of the present invention, a zinc oxide nanostructure layer is laminated on the other side of the contact surface between the copper-containing layer and the graphene-containing layer.

As another embodiment of the present invention, the graphene of the graphene-containing layer may be characterized by having a structure of a single layer or a multilayer of carbon atoms. The graphene-containing layer may contain graphene and copper and the content thereof is preferably 0.001 to 99.9999 wt% of graphene and 0.0001 to 99.999 wt% of copper, preferably 0.001 to 5 wt% of graphene, and 95 to 99 wt% of copper To 99.999% by weight.

In still another embodiment of the present invention, the zinc oxide nanostructure of the zinc oxide nanostructure-containing layer may be a nanowall or nanorods structure, and may be a nanowire structure . The zinc oxide nanostructure-containing layer may contain 0.005 to 30 wt%, preferably 0.005 to 5 wt%, and more preferably 0.01 to 2 wt% of the zinc oxide nanostructure .

In another embodiment of the present invention, the heat radiator of the present invention may further include an aluminum (Al) -containing layer, and the heat radiator of the present invention may be in the form of a film or a sheet .

According to another aspect of the present invention, there is provided an LED device including the heat conductor of the various embodiments of the present invention described above.

Further, the LED element of the present invention may be characterized in that the heat dissipating body is included between the aluminum substrate and the heat sink.

The heat dissipator of the present invention has a very excellent dynamic heat dissipation effect, is easy to apply in the field of the heat dissipator, is excellent in the reliability and economical efficiency of the heat dissipater, and can greatly increase the light efficiency and long-term life of the LED device.

1 is a schematic diagram showing the degree of heat loss of the LED illumination.
FIGS. 2 to 4 are schematic views showing an embodiment of the heat radiator of the present invention.
5 is a schematic view showing a manufacturing process of graphene used in the present invention.
FIG. 6 is a schematic view showing one embodiment of a method for producing a ZnO seed used in a ZnO nanostructure used in the present invention.
FIG. 7 is a schematic view showing one embodiment of a method for producing a ZnO nanostructure used in the present invention.
8A and 8B are photographs showing T-CVD (chemical vapor deposition) equipment and process conditions used in preparation of graphene of Preparation Example 1, respectively.
Fig. 9 shows a schematic view of a graphene production process of Preparation Example 1. Fig.
Fig. 10 shows the results of Raman analysis measurement of Experimental Example 1. Fig.
11 is a FE-SEM (Field Emission Scanning Electron Microscope) photograph of each of the ZnO nanostructures prepared in Preparative Example 2-1, wherein A to C are spherical, nano-wall, and nano-bar.
12 is a schematic view of a method for measuring the heat radiation efficiency of a ZnO nanostructure through the thermal imaging camera in Experimental Example 2. FIG.
Fig. 13 is a photograph of heat radiation efficiency measurement of the heat radiation film using the thermal imaging camera performed in Experimental Example 3. Fig.
14 is an actual photograph of an LED circuit to which the heat radiation film of Production Example and Example 4 is applied.
Fig. 15 is a photograph showing the thermal distribution of the LED device after being turned on and off for 30 minutes, which is a measurement of thermal change using the thermal imaging camera of Experimental Example 4. Fig.

As used herein, the term " laminate " refers to a laminate formed by forming one or more layers on one side of a layer, and each layer is directly bonded by a method such as coating or by means of an adhesive Quot; and " the "

Hereinafter, the present invention will be described in more detail.

The present invention relates to a heat dissipator, comprising: a graphene-containing layer; And a copper (Cu) -containing layer, which may be in the form of a stack of graphene-containing layers on one or both sides of the copper-containing layer, as shown in Figures 2A and 2B in one embodiment, The graphene-containing layer may be laminated on one side of the copper-containing layer.

The copper-containing layer preferably has an average thickness of 0.001 mm to 0.5 mm, preferably an average thickness of 0.002 mm to 0.3 mm, more preferably 0.005 mm to 0.25 mm. If the copper-containing layer is less than 0.001 mm, Containing layer may be difficult to manufacture and handling. When the thickness exceeds 0.5 mm, the heat radiation effect is deteriorated by the phenomenon of peeling or the like.

In the heat dissipator of the present invention, the graphene containing layer may be a single layer or a multilayer stacked layer, preferably a single layer or a layer of two to four layers. It is preferable that the graphene-containing layer has an average thickness of 0.05 nm to 50 nm, preferably 0.05 nm to 5 nm, more preferably 0.1 nm to 4 nm, 0.05 nm is difficult to manufacture, and 50 nm It is preferable to have an average thickness within the above range since it is not preferable because it is bulked. It is characterized that the effect of increasing the heat dissipation effect is hardly exhibited even when the number of layers is more than that.

The graphene-containing layer preferably contains 0.001 to 99.9999% by weight of graphene and 0.0001 to 99.999% by weight, preferably 0.001 to 5% by weight and 95 to 99.999% by weight of copper, more preferably 0.001 to 2% By weight and 98 to 99.999% by weight of copper. If the graphene content is less than 0.001 wt%, sufficient heat dissipation effect may not be obtained. If the graphene content is more than 99.9999 wt%, the heat dissipation synergistic effect is insufficient.

The heat dissipator of the present invention may further include a zinc oxide (ZnO) structure containing layer. In one embodiment, as shown in FIGS. 3A and 3B, a contact surface between the copper containing layer and the graphene containing layer And a zinc oxide nanostructure layer is laminated on the other side of the zinc oxide nanostructure layer.

The zinc oxide nanostructure of the zinc oxide nanostructure-containing layer may be a nanowall or nanorods structure. It is preferable that the nanowire structure is used in view of the initial dynamic heat dissipation effect.

In the present invention, it is preferable that the zinc oxide (ZnO) nanostructure-containing layer has an average thickness of 50 nm to 200 nm, preferably 100 to 150 nm, and if it is less than 50 nm, There is a problem that there is no problem, and even when the thickness exceeds 200 nm, there is a problem that the cost increases without any further dynamic heat radiation synergistic effect, and therefore, it is preferable to have an average thickness within the above range.

The zinc oxide nanostructure-containing layer contains the zinc oxide nanostructure in an amount of 0.005 to 30 wt%, preferably 0.005 to 5 wt%, more preferably 0.01 to 2 wt%, still more preferably 0.01 To 1% by weight. The zinc oxide nanostructure-containing layer may further contain, in addition to the zinc oxide nanostructure, a copper-containing layer of several nm thickness, an aluminum-containing layer of several nm thickness, and the like.

Further, as another embodiment of the present invention, the above-described heat radiator of the present invention may further include an aluminum (Al) -containing layer to obtain a dispersion effect of heat radiation, and in one embodiment, Lt; RTI ID = 0.0 > a < / RTI > zinc oxide-containing layer.

It is preferable that the aluminum-containing layer has an average thickness of 1,200 nm or less, preferably 50 nm to 1,200 nm, more preferably 50 nm to 250 nm. If the aluminum-containing layer has an average thickness of 50 nm to 1,200 nm, peeling of the Al layer may occur Therefore, it is preferable to have an average thickness within the above range.

As shown in FIG. 2 to FIG. 4C, when the thicknesses of the copper-containing layer and the graphene-containing layer are appropriately adjusted and stacked alternately with each other, the heat dissipator of the present invention can further increase the heat radiation effect When the copper-containing layer and the graphene-containing layer are regarded as one layer, they may be formed in two or more layers. For example, the copper-containing layer-graphen containing layer-copper containing layer-graphen containing layer, or graphen containing layer-copper containing layer-graphen containing layer-copper containing layer-graphen containing layer, Layer-graphene-containing layer-copper-containing layer-graphene-containing layer-copper-containing layer-graphene-containing layer.

The shape of the above-described heat radiator of the present invention is not particularly limited, but is preferably in the form of a film or a sheet.

Hereinafter, a method for producing graphene used in the present invention will be described.

The graphene used in the present invention can be produced by a general method used in the art, and preferably it is manufactured by chemical vapor deposition. CVD (Chemical Vapor Deposition) is a method of synthesizing graphene using a transition metal that is well formed of carbon and a carbide alloy at a high temperature or adsorbs carbon well as a catalyst layer, and is characterized in that at 950 ° C to 1,100 ° C, With a mixed gas of methane and hydrogen to adsorb carbon to the transition metal catalyst layer; Crystallizing carbon on the catalyst layer surface through cooling to form a graphene crystal structure; And removing and separating the catalyst layer from the formed graphene crystal structure. A schematic diagram of a method of synthesizing graphene is shown in FIG.

The transition metal catalyst layer is not particularly limited, but it is preferable to use a copper catalyst layer.

In addition, the step of forming the graphene crystal structure may include coating the formed graphene crystal structure with polymethyl methacrylate (PMMA); And transferring the graphene crystal structure coated with the PMMA onto a nickel etchant.

Also, the method of synthesizing the graphene of the present invention comprises: removing the catalyst layer and depositing the separated graphene crystal structure on a silicon wafer, followed by washing with acetone; And heating the PMMA under a nitrogen gas to 120 ° C to 130 ° C to remove the PMMA.

Hereinafter, a method for producing the ZnO nanostructure used in the present invention will be described.

First, the ZnO seed mechanism will be described. Zinc oxide is a material having an anisotropic and nonstoichiometric defect structure in a crystal structure. When zinc oxide thin film grows, the diameters of Zn and O are large Because they are different, lattice-shaped Zn or oxygen vacancies are generated. In this crystal structure, the distance between the ions in the c-axis direction is shorter than the distance between the ions in the other direction, and thus the ratio of the effective ionic charge is 1: 1.2. The polar axis of zinc oxide is the c axis.

(0001) plane and the (000-1) plane which are perpendicular to the c axis, and the c axis parallel to the (10-10) plane is a polar axis. Since zinc oxide is partially ion-bonded, the (0001) plane consisting of Zn atoms has a relatively positive charge and the (000-1) plane composed of only O atoms has a negative charge. Due to this bonding property, the Zn layer has a relatively large surface energy, fast growth rate, large corrosion and abrasion resistance as compared with the O layer. Growth in the (0001) direction of zinc oxide thin film has the lowest surface energy, and therefore, the c-axis orientation is strong and thus the mechanical coupling coefficient is high. For this reason, zinc oxide can realize various one-dimensional nanostructures such as nanorods, nanowires, nanotips, nanowires, and nanodevils grown in c-axis, and further suppresses c-axis orientation by controlling growth conditions. , Nanocapsules, nanoparticles, and nanoribbons. In addition, a multi-structure of tree-shaped structure is possible due to its high growth potential in a single precursor (0001) family plane.

The ZnO nanostructure used in the present invention can be prepared by a general method used in the art, but it is preferably prepared by hydrothermal synthesis.

More specifically, the method includes: fabricating ZnO seeds; And hydrothermally synthesizing the ZnO seed to form a ZnO nanostructure.

The step of preparing the ZnO seed may include heating a mixture of zinc acetate dehydrate (Zn (CH ₃ COO) ₂₂ H ₂ O) and alcohol to 320 ° C to 380 ° C; Spin coating the substrate while dipping the mixture; And washing and drying the ZnO seed. The method of manufacturing the ZnO seed is shown in FIG.

Preferably, the alcohol is a C1-C2 alcohol, preferably ethanol, and the spin coating is performed at an average rotation speed of 2,000 to 3,000 rpm / sec. N ₂ ) gas, and then heat-dried at a temperature of about 90 to 110 ° C.

Through such a method, zinc nitrate hexahydrate (Zn (NO ₃ ) ₂ 6H ₂ O, hereinafter referred to as ZNH) can be obtained as a ZnO seed.

In addition, the step of growing the ZnO nanostructure comprises: preparing a ZnO nanostructure growth derivative and a dissolving solution in which the ZNH is dissolved in deionized water; Heating the solution to 320 DEG C to 380 DEG C; And growing the ZnO nanostructure in an atmosphere of 90 ° C to 100 ° C for 30 minutes to 90 minutes. The method of the present invention may further include a step of washing, and an embodiment of growing the ZnO nanostructure is shown in FIG.

The structure growth derivative is not particularly limited, but hexamethylenetetramine (HMT) is preferably used.

The mechanism of growth of ZnO nanostructures by hydrothermal synthesis is described below. First, when HMT is dissolved in deionized water, hydroxide ion is generated as shown in the following reaction formula (1).

[Reaction Scheme 1]

And ZNH is dissolved in deionized water and ionized into zinc ion (Zn ^{2 +} ) and nitrate ion (NO ₃ ^- ) as shown in the following reaction formula 2.

[Reaction Scheme 2]

When the zinc ion and the hydroxide ion generated above the predetermined concentration are generated as shown in the following reaction formula 3, zinc hydroxide (Zn (OH) ₂ ) - (s) is obtained.

[Reaction Scheme 3]

Then, the hydroxide ion in the solution receives thermal energy by hydrothermal treatment to form ZnO, and the formed ZnO constitutes a nanostructure perpendicular to the substrate along the nucleus by HMT. Constant structure can be obtained by maintaining the reaction time while maintaining the constant temperature.

The seed layer facilitates the nucleation of ZnO by homologous bonds and the growth of ZnO nanostructures occurs rapidly when nucleation occurs. The reason for the vertical growth of ZnO nanorods and nanowalls is that the growth rate in the c-axis direction is fast due to the material properties.

By using such a mechanism, zinc oxide nanostructures can be manufactured through various conditions and parameters depending on temperature, growth time, pH and reagent molar ratio.

According to another aspect of the present invention, there is provided an LED device including the heat conductor of the various embodiments of the present invention described above.

Further, the LED element of the present invention may be characterized in that the heat dissipating body is included between the aluminum substrate and the heat sink.

Hereinafter, the present invention will be described in more detail with reference to preferred embodiments. It will be understood by 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. It will be clear to those who have knowledge.

[Example]

Preparation Example 1-1: Preparation of graphene

(1) A copper foil was prepared as a copper catalyst, and then the copper foil was charged into a T-CVD (chemical vapor deposition) equipment shown in FIG. 8A. The temperature is raised to 1000 deg. C, and hydrogen gas is continuously flowed at 300 deg. C at 10 sccm. Thereafter, the substrate was annealed at 1,000 ° C. for 30 minutes, and the surface oxide film was removed. Then, carbon was adsorbed on the copper foil by reacting with a mixed gas of 20 sccm of methane and 10 sccm of hydrogen for 30 minutes, Cool for a period of time. The CVD process conditions are as shown in Fig. 8B.

(2) Next, the graphene synthesis chamber containing the carbon-adsorbed copper foil was taken out, and then gradually cooled to crystallize the carbon on the surface of the copper foil to form a graphene crystal structure. Next, this was coated with a polymethyl methacrylate resin (PMMA resin), and then transferred onto a nickel etchant, with the copper foil facing the nickel echinum. Next, the copper foil was removed, separated and washed, and then a graphene crystal structure was deposited on the silicon wafer. Next, the substrate was washed with acetone, blown with a nitrogen gas, and then heated at 125 ° C with a hot plate to remove PMMA, thereby producing graphene. The manufacturing process is shown in FIG.

Experimental Example  1: through Raman analysis Grapina  Measure

The graphene prepared in Preparation Example 1 was confirmed using a micro Raman spectroscope (manufacturer: Renishaw, model name System 1000), and the results are shown in FIG.

Referring to FIG. 10, a peak can be observed at about 1580 cm ^-1 , which is called a G-band and is caused by a vibration mode corresponding to the stretching of carbon-carbon bonds. This is a peak commonly found in graphite materials. And we can see the peak near 1300 ~ 1400 cm ^-1 , which is called D-band, appears when the sp ² crystal structure is defective, and when atomic defect occurs, it shows strong signal. This peak is often used as an indicator of the degree of specimen defects.

The presence of G-band peaks was confirmed by Raman analysis and the presence of graphene was confirmed, and the D-band peaks were also very weak. Thus, it was confirmed that homogeneous graphene having few defects was produced.

Preparation Example  1-2: Grapina  ≪ / RTI >

A graphene-containing copper layer was prepared using the graphene monolayer prepared in Preparation Example 1-1.

Preparation Example 2-1: Preparation of ZnO nanostructure

(One) ZnO  Manufacture of seeds

0.18 g of zinc acetate dehydrate was mixed with 100 ml of ethanol and then heated to 350 캜. Next, the spinning machine was mounted on a spin coater, spin-coated with the mixed solution, and the rotation rate was 50 rpm / sec.

Next, the dipped substrate was dried at 100 DEG C for 10 minutes to obtain zinc nitrate hexahydrate (ZNH).

(2) ZnO  Manufacture of nanostructures

Next, 18 g of the above ZNH and 87 g of hexamethylenetetramine (HMT) were added to 250 ml of DI water and stirred and then heated to 350 ° C. Next, the ZnO nanostructure was grown by drying at 95 ° C. for 60 minutes, and then washed with deionized water to obtain a ZnO nanostructure.

The fabricated ZnO nanostructures were able to obtain nanostructures in the form of microspheres, nanowalls and nanorods depending on the treatment conditions.

FE-SEM (Field Emission Scanning Electron Microscope) photographs of the ZnO nanostructures thus produced are shown in FIGS. 11A to 11C, respectively.

Experimental Example 2: Analysis of thermal efficiency of a ZnO nanostructure using a thermal imaging camera

As shown in FIG. 12, the thermal efficiency of each of the spherical, nano-wall type and nanoporous ZnO nanostructures prepared in Preparation Example 2-1 was measured using a thermal imaging camera, and the results are shown in Table 1 below. The non-ZnO of Table 1 is the measurement of the heat radiation efficiency of the LED by utilizing the coating of the nanostructure without ZnO coating.

In the experimental method, each ZnO nanostructure was heated to a hot plate for 5 minutes at the same temperature, and the thermal efficiency of each ZnO nanostructure was measured with a thermal imaging camera.

Shape (temperature) Non-ZnO Spherical -ZnO Nanoprobes - ZnO Nano Wall Type - ZnO 0 sec 180.0 DEG C 180.0 DEG C 180.0 DEG C 180.0 DEG C 20 sec 177.2 DEG C 172.3 DEG C 165.8 ° C 159.5 DEG C

The heat dissipation effect of the electronic and electrical parts is determined by the initial dynamic heat release, and it is confirmed that the dynamic heat release effect of the ZnO nanostructure is superior to that of the non-ZnO. Also, it can be seen that the nano-wall type has the best initial dynamic heat release. In addition, the nanoparticles showed somewhat less dynamic heat release than the nanoparticles, but showed similar results to the nanoparticles. Therefore, it has been confirmed that the nanoparticle-type ZnO nanostructure is very suitable for use as a heat-radiating material, and since the nanoparticle-type ZnO nanostructure has better adhesion than the nanoprobe, .

Example  One

(2 nm x 3 cm) in the form of a film was prepared by laminating the graphene-containing layer (2 nm) prepared in Preparation Example 1-2 on one side of a copper foil having a thickness of 0.07 mm.

Example 2

The nano-wall type ZnO nanostructure-containing layer prepared in Preparation Example 2-2 was laminated by wet method on one surface of the graphene-containing layer of the heat discharger prepared in Example 1, .

Example 3

An aluminum layer was laminated on one surface of the ZnO nanostructure-containing layer of the heat dissipator fabricated in Example 2 using a sputtering method to produce a heat dissipator in the form of a film as shown in FIG. 4A.

Example 4

A heat dissipator was prepared in the same manner as in Example 1 except that a 1.5 nm graphene-containing layer (produced by the same method as in Preparation Example 1-2) was used in place of the 2 nm graphene-containing layer, (Graphene-containing layer-copper foil (copper-containing layer) -graffin-containing layer) was prepared as shown in Table 2 below.

Example 5

A heat radiator was manufactured in the same manner as in Example 2 except that a 0.05 mm copper foil was used in place of the 0.07 mm copper foil, and a heat radiator of the form shown in Fig. 3B was prepared as shown in Table 2 below.

Example 6

A heat radiator was manufactured in the same manner as in Example 3 except that a 0.05 mm copper foil was used in place of the 0.07 mm copper foil and a heat radiator of the form shown in Fig.

Comparative Example 1

As a comparative sample, a heat-radiating film which had been used in the past was prepared from only 0.25 mm copper plate (copper foil).

Comparative Example 2

A heat radiation film was produced in the same manner as in Example 4, except that a copper foil having a thickness of 0.25 mm was used.

Comparative Example 3

A heat radiation film was produced in the same manner as in Example 5, except that a copper foil having a thickness of 0.25 mm was used.

Comparative Example 4

A heat radiation film was produced in the same manner as in Example 6, except that a copper foil having a thickness of 0.25 mm was used.

division Heat-Release Film Laminating Order and Thickness Example 1 Copper foil (0.07 mm) -> graphene-containing layer (2.0 nm) Example 2 (0.07 mm) -> graphene-containing layer (2.0 nm) -> ZnO nanostructure-containing layer (130 nm) Example 3 Copper foil (0.07 mm) -> graphene-containing layer (2.0 nm)
-> ZnO nanostructure-containing layer (130 nm) -> Al-containing layer (200 nm) Example 4 (1.5 nm) -> copper foil (0.5 mm) -> graphene-containing layer (1.5 nm) Example 5 Graphene-containing layer (1.5 nm) -> copper foil (0.05 mm)
-> graphene-containing layer (1.5 nm) -> ZnO nanostructure-containing layer (130 nm) Example 6 (1.5 nm) -> copper foil (0.05 mm) -> graphene-containing layer (1.5 nm)
-> ZnO nanostructure-containing layer (130 nm) -> Al-containing layer (200 nm) Comparative Example 1 Copper foil (0.25 mm) Comparative Example 2 (1.5 nm) -> copper foil (0.25 mm) -> graphene-containing layer (1.5 nm) Comparative Example 3 Graphene-containing layer (1.5 nm) -> copper foil (0.25 mm)
-> graphene-containing layer (1.5 nm) -> ZnO nanostructure-containing layer (130 nm) Comparative Example 4 (1.5 nm) -> copper foil (0.25 mm) -> graphene-containing layer (1.5 nm)
-> ZnO nanostructure-containing layer (130 nm) -> Al-containing layer (200 nm)

Experimental Example 3: Analysis of heat radiation efficiency of a heat radiating film for a thermal camera 1

The heat radiation effect of each of the heat radiation films prepared in Examples 1 to 6 and Comparative Examples 1 to 4 was tested and the results are shown in Table 3 below. 13B, each of the heat radiation films was inserted into the LED element and the heat sink, and then heated on a hot plate for 5 minutes. Thereafter, the temperature change was observed using the thermal imaging camera used in Experimental Example 2 , And thermal efficiency.

division 0 sec 10 sec 20 sec For 20 seconds
Temperature change Example 1 158.6 DEG C 152.4 DEG C 145.9 ° C 12.7 ℃ Example 2 152.7 DEG C 145.5 DEG C 138.9 ° C 13.8 ℃ Example 3 155.4 DEG C 147.1 DEG C 139.7 ° C 15.7 DEG C Example 4 158.1 DEG C 150.5 DEG C 143.7 ° C 14.4 DEG C Example 5 152.3 DEG C 144.8 DEG C 137.5 ℃ 14.8 ° C Example 6 154.5 DEG C 146.6 ° C 137.3 DEG C 16.8 DEG C Comparative Example 1 135.8 ° C 133.5 DEG C 129.9 ° C 5.9 ° C Comparative Example 2 138.4 DEG C 136.3 DEG C 133.1 DEG C 5.3 ° C Comparative Example 3 134.4 DEG C 130.3 DEG C 126.2 DEG C 8.2 ℃ Comparative Example 4 140.7 DEG C 137.1 DEG C 132.2 DEG C 8.5 ° C

As shown in Table 3, in Examples 1 to 6 of the present invention, it was confirmed that the heat radiation effect was excellent at a temperature change of 12 ° C or more for 20 seconds. However, in the case of Comparative Example 1 which is a heat dissipation made of a copper foil only, the temperature change was less than 6 占 폚 and the heat dissipation effect was very low.

In Comparative Examples 2 to 4 in which a graphene-containing layer was laminated on both sides of a 0.25 mm copper foil, it was confirmed that the heat radiating effect was lower than in Examples 1 to 3 in which a graphene containing layer was laminated on only one side of the copper foil. Further, in the case of Comparative Examples 2 to 4, it was confirmed that the heat dissipating effect was significantly lower than those of Examples 4 to 6 in which the double-side graphen containing layer of 0.05 mm copper foil having a total thickness of the heat dissipating film was laminated.

Example 7

(0.07 mm) -> graphene-containing layer (1.5 nm) -> copper foil (0.05 mm (thickness)) was formed on the 0.07 mm copper foil by laminating the film of Example 6 on the 0.07 mm copper foil, ) -> a graphene-containing layer (1.5 nm) -> a ZnO nanostructure-containing layer (130 nm) -> an Al-containing layer (200 nm).

Manufacturing example  1 to 3 and Comparative Manufacturing Example  1-4

The actual LED circuit was fabricated as shown in Fig. 13B and Fig. 14 using the heat-radiating films shown in the following Table 4 produced in Examples 1, 3, 7 and Comparative Examples 1 to 4, Examples 1 to 3 and Comparative Production Examples 1 to 4 were respectively performed.

division Heat-radiating film 14 shows Heat-Release Film Laminating Order and Thickness Production Example 1 Example 1 5 times Copper foil (0.07 mm) -> graphene-containing layer (2.0 nm) Production Example 2 Example 3 No. 4 Copper foil (0.07 mm) -> graphene-containing layer (2.0 nm)
-> ZnO nanostructure-containing layer (130 nm) -> Al-containing layer (200 nm) Production Example 3 Example 7 8 times (1.5 nm) -> ZnO nanostructure-containing layer (130 nm) -> Al-containing layer (200 nm) -> Copper foil (0.07 mm) nm) Manufacturing Comparative Example 1 Comparative Example 1 No. 7 Copper foil (0.25 mm) Manufacturing Comparative Example 2 Comparative Example 2 No. 6 (1.5 nm) -> copper foil (0.25 mm) -> graphene-containing layer (1.5 nm) Manufacturing Comparative Example 3 Comparative Example 3 No.2 Graphene-containing layer (1.5 nm) -> copper foil (0.25 mm)
-> graphene-containing layer (1.5 nm) -> ZnO nanostructure-containing layer (130 nm) Manufacturing Comparative Example 4 Comparative Example 4 number 3 (1.5 nm) -> copper foil (0.25 mm) -> graphene-containing layer (1.5 nm)
-> ZnO nanostructure-containing layer (130 nm) -> Al-containing layer (200 nm)

Experimental Example 4: Analysis of heat radiation efficiency of heat-radiating film for a thermal camera 2

The actual LEDs manufactured in Production Examples 1 to 3 and Comparative Production Examples 1 to 4 were turned on for 30 minutes and then turned off to observe the temperature change with a thermal imaging camera. The results are shown in FIG. 15 and the following table.

15, the LED devices No. 4 (Production Example 2), No. 5 (Production Example 1), and No. 8 (Production Example 3) to which the heat-radiating film of the present invention was applied exhibited very poor or almost no red color distribution This is because the heat dissipation from the LED element is very good.

However, it can be seen that the distribution of red color is very dark in cases 1 to 3 and 6 to 7, which means that after the internal heat of the LED device has risen, the heat dissipation from the LED device has not been performed well.

division Heat-radiating film 14, After lighting for 30 minutes, the measured temperature Production Example 1 Example 1 5 times 122.4 DEG C Production Example 2 Example 3 No. 4 111.2 DEG C Production Example 3 Example 7 8 times 105.1 DEG C Manufacturing Comparative Example 1 Comparative Example 1 No. 7 126.6 ° C Manufacturing Comparative Example 2 Comparative Example 2 No. 6 130.8 ℃ Manufacturing Comparative Example 3 Comparative Example 3 No.2 146.5 DEG C Manufacturing Comparative Example 4 Comparative Example 4 number 3 119 ℃

15 and Table 5, it was confirmed that Production Example 2, which is a heat-radiating film in which a ZnO nanostructure-containing layer and an aluminum-containing layer are further laminated, is superior to Production Example 1. From the fact that the measurement temperature of Production Example 3 is lower than that of Production Example 2, it was confirmed that the heat radiation film laminated two times as compared with the case where the graphen-containing layer and the copper-containing layer were alternately laminated once was more excellent in heat radiation effect . However, the production examples 1 to 3 proposed by the present invention were more excellent in heat radiation effect than the production comparison examples 1 to 4. However, in Comparative Production Example 4, the heat dissipation effect was good, which is considered to be the result of introducing the ZnO nanostructure and the aluminum-containing layer as described in the present invention.

The heat dissipation effect of the heat dissipator of the present invention was confirmed to be excellent through the above-described embodiments and experiment examples. By applying the heat dissipator of the present invention to LED devices such as LED lighting devices, However, it is expected that the lifetime of LED devices can be improved by about 200%. It is expected that the heat radiator of the present invention can replace not only LED devices but also heat radiation films and heat radiation sheets for various electric and electronic products such as display devices such as LCDs, semiconductor packages, modules, computers, .

Claims (14)

A graphene-containing layer; And a copper (Cu) -containing layer. The heat dissipator according to claim 1, further comprising a zinc oxide (ZnO) structure containing layer. The heat dissipator according to claim 1, wherein a graphene-containing layer is laminated on one side or both sides of the copper-containing layer, and the copper-containing layer has an average thickness of 0.001 mm to 0.5 mm. 4. The heat dissipator according to claim 3, wherein the copper-containing layer and the graphen-containing layer are alternately laminated to form one layer, and the one layer is alternately laminated alternately. 3. The heat dissipator according to claim 2, wherein the zinc oxide nanostructure layer is laminated on the other side of the contact surface between the copper-containing layer and the graphene-containing layer. The method of claim 1, wherein the graphene-
0.001 to 99.9999 wt% of graphene, and 0.0001 to 99.999 wt% of copper. The method of claim 6, wherein the graphene-
0.001 to 2 wt% of graphene, and 98 to 99.999 wt% of copper. The heat dissipator according to claim 2, wherein the zinc oxide nanostructure is a nanowall or nanorods structure. The zinc oxide nanostructure-containing layer according to claim 2, wherein the zinc oxide nanostructure-
And 0.005 to 30% by weight of the zinc oxide nanostructure. The zinc oxide nanostructure-containing layer according to claim 2, wherein the zinc oxide nanostructure-
And 0.005 to 5% by weight of the zinc oxide nanostructure. The heat dissipator according to any one of claims 1 to 10, further comprising an aluminum (Al) -containing layer. The heat sink according to any one of claims 1 to 10,
Wherein the heat dissipation member is in the form of a film or a sheet. An LED device comprising the heat sink of claim 12. 14. The LED device according to claim 13, wherein the LED element comprises the heat discharger between the aluminum substrate and the heat sink.

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