CN101448380A

CN101448380A - Radiating base material

Info

Publication number: CN101448380A
Application number: CNA2007101937647A
Authority: CN
Inventors: 林经协
Original assignee: JIUZHENG PHOTOELECTRIC CO Ltd
Current assignee: JIUZHENG PHOTOELECTRIC CO Ltd; Powertip Tech Corp
Priority date: 2007-11-26
Filing date: 2007-11-26
Publication date: 2009-06-03

Abstract

The invention discloses a radiating base material, which uses a graphite base material as a body with a diamond-like carbon structure plated on the surface of the graphite base material, so that the body and the diamond-like carbon structure can be formed into a whole. Furthermore, fiber with high thermal conductivity can be contained in the body. The surface radiating velocity of the diamond-like carbon structure can be over ten times higher than common metal, and the strength of the diamond-like carbon structure can make up the brittleness of the graphite base material. Therefore, the radiating base material has the advantages of high strength and high thermal conductivity.

Description

Heat radiating material

Technical field

The present invention relates to a kind of heat radiating material, refer to a kind of heat radiating material that class is bored the carbon plated film that is coated with especially.

Background technology

Along with science and technology is maked rapid progress, electronic product is constantly released, central processing unit, plasma-screen television, light-emittingdiode, liquid crystal panel, each quasi-instrument, circuit in the communication device etc. and its relevant peripheral are no lack of the electronic component for miniaturization, and the applied heat dissipation element of electronic component mainly is a thermal conductivity of utilizing the metal material, copper for example, the diffusing hot Sushi sheet that aluminium is made, it is attached at the electronical elements surface that needs heat radiation, reach radiating effect, but, with copper (385W/mK), the conductive coefficient of aluminium (226W/mK), it must keep certain area of dissipation, can reach the effect of heat radiation.

In addition, also can utilize the higher graphite of coefficient of heat transfer to make fin and be dispelled the heat, but that the fin that graphite is made has is frangible, the problem of dry linting.In order to improve the problem of graphitic embrittlement, dry linting, plate a metal level at graphite surface, in order to problems such as the fragility that remedies graphite, dry lintings, still, plate a metal level at graphite surface and still have metal level thermal conductivity problem, need further improvement.

At minimum electronic component (LED), general LED chip area is less than 1mm, if its peripheral heat radiating material is heat sink to be copper sheet or aluminium flake, because the heat radiating material of LED is minimum, can not be as CPU You Sushi sheet, and after the used heat of LED conducts to heat radiating material, need its surface of mat to spread to heat energy in the air of periphery with infrared radiation, and the surface smoothing of copper or aluminium and have metallic luster, (less than 100 ℃) its radiance has only about 2% of ideal black-body at low temperatures, and if metallic surface oxidation or be coated with pitch-dark, then its radiance can significantly improve (about 60%), but the pyroconductivity of the material of high radiant rate is very low, and this thermal resistance material is difficult to effectively get rid of hot-fluid.The base material of LED periphery can only be taken away heat in its surface of mat air molecule random collision at present, and substrate surface is if coating one deck carbon black can be taken into account the heat conduction radiation, and still, carbon black but peels off easily and pollutes, and is more impracticable.

Therefore, with regard to this type of Small electronic component of LED, the heat radiating material that how to obtain possessing heat-sinking capability still is a big problem.

Summary of the invention

The object of the present invention is to provide a kind of heat radiating material, this heat radiating material has the characteristics of high strength, high thermal conductivity, good heat dissipation effect.

In order to achieve the above object, the present invention is by the following technical solutions:

A kind of heat radiating material is characterized in that: this heat radiating material is a body with a graphite substrate, is coated with one deck class in the graphite substrate surface and bores carbon (Diamond-Like Carbon) structure.

A kind of heat radiating material is characterized in that: this heat radiating material is body with the graphite substrate, and body contains the fiber of high thermal conductivity, and is coated with one deck class brill carbon (Diamond-Like Carbon) structure in the graphite substrate surface.

Advantage of the present invention is:

Bore combining of carbon-coating by graphite substrate with class, each is with the characteristic of high thermal conductivity, class is bored the surface radiating speed ratio common metal of carbon (DLC) more than high ten times, and characteristic with high strength, high rigidity, it is coated on the graphite substrate surface, then can complement each other, reach the effect of efficiently radiates heat.

And, class is bored carbon structure and is plated on the graphite substrate surface, and the intensity that this layer class bored carbon structure can remedy the fragility of graphite substrate, and makes its integral body become the heat radiating material that has high strength, high thermal conductivity concurrently, and the heat energy that light-emittingdiode produced can effectively transmit through heat radiating material and distribute.

Description of drawings

Fig. 1 is that body of the present invention bores the generalized section that carbon combines with class;

Fig. 2 is the schematic diagram that heat radiating material of the present invention is provided with light-emittingdiode;

Fig. 3 is that the body that the present invention has a high thermal conductivity fiber bores the generalized section that carbon combines with class;

Fig. 4 is that association class of the present invention bores carbon in the schematic diagram of body.

Embodiment

Present embodiment provides a kind of heat radiating material, and it is a body with a graphite substrate, and is provided with one deck class brill carbon structure in body surface.See also Fig. 1 to shown in Figure 3, this heat radiating material comprises a body 1 and one deck class brill carbon structure 2, in the present embodiment, is example with the heat radiating material structure of installing a light-emittingdiode (LED) 3, wherein:

This body 1 is made by graphite, and the shape of this body 1 can be made into different shapes according to the demand of object (LED), and this layer class bored the surface that carbon structure 2 is located at this body 1.

In addition, can add suitable high thermal conductivity fiber 4 in the composition graphite of this body 1, see shown in Figure 3, so that body 1 forms the composite material with fiber, and this high thermal conductivity fiber 4 can utilize copper cash (diameter 100 μ, length 1mm) pinches pressurization through overmulling and form, and give aforesaid class in its surface plating and bore carbon structure 2, and then form the structure that a high heat passes.

For aforesaid graphite substrate 1, its preferable density is 0.02 to 2.35g/cm ³Between, and graphite substrate 1 can be utilized nature crystalline flake graphite, expanded graphite or Delanium to be applied to make.For aforesaid high thermal conductivity fiber 4, its preferable draw ratio is mainly between 1～5000, and can use different fiber materials to be processed into body, so that it becomes high strength, high conductance graphite substrate, its fiber material comprise metal, pottery, macromolecule, material with carbon element, copper, aluminium, albronze, carborundum, aluminium oxide, high heat pass pottery, carbon fiber, graphite fibre, nano carbon tubes, diamond micro mist, must the shape carbon fiber, vapor deposition based carbon fiber, carbon black, how rice carbon ball or material such as how meter carbon is protruding.

Because it is the amorphous carbon film of class graphite key (Graphite-Like Bond) and class diamond key (Diamond-Like Bond) combination that class is bored carbon (Diamond-Like Carbon or DLC), and being called tetrahedron, the DLC of pure carbon do not have brilliant carbon (Tetrahedral Amorphous Carbon) or non-crystal diamond (a-D), non-crystal diamond is that not hydrogeneous pure carbon class is bored carbon, diamond bond contained in it is up to 85%, so, non-crystal diamond is similar to the diamond property of CVD deposition, and extremely anti-strong acid of non-crystal diamond and oxidant, even be dropped in the chloroazotic acid and also can not respond.

The plated film that class is bored carbon (Diamond-Like Carbon or DLC) is level and smooth (atom level) or coarse relatively (how meter level) extremely, and how the coarse non-crystal diamond (pure carbon DLC) of meter level is the most effective heat radiation surface, the far infrared that can be equivalent to solar constant (Solar Constant) in about 100 ℃ of ejaculations, the non-crystal diamond plating can reduce about 18 ℃ of the operation temperature of wafer when graphite substrate surperficial.The field emission gun, battle array that non-crystal diamond is desirable especially, when it was coated on the electrode of cold cathode fluorescent lamp (CCFL), it starts electricity can be reduced to about 600V by 700V.The thermoelectric interface that non-crystal diamond is still the most responsive, when it is heated to 100 ℃, its magnitude of current can be up to ten thousand times than normal temperature, and this unique thermal electrical characteristics of non-crystal diamond also can be used for backlight, plasma-screen television, the Field Emission Display (FED) of LCD, even solar cell.

And, DLC is the hardest and the most sliding plated film, its hardness far surpasses other plated film (as TiCN), even can be near the true hardness of diamond, and passive device is (as heat radiation, discharge) then can strengthen the hardness of DLC, to bring into play its usefulness, and the coating of DLC can very smooth-going (atom level) or how to be had a rice structure, how DLC can form the rice structure, the level and smooth metal of its surface area ratio is increased more than ten times, thereby the surface atom density of DLC can Duo about three times than metal, therefore, the DLC of atom level is fit to the application of low frictional factor, and how the DLC of meter level then can strengthen radiant heat or have an effect of emission.

On the processing procedure, DLC can utilize physical vapour deposition (PVD) (Physical Vapor Deposition or PDV) to be plated on the base material, forms because DLC is amorphous uneven carbon atom accumulation, and base material is hard more usually, and then the adhesive strength of DLC is high more.In the PVD processing procedure, be that the gas (as methane, acetylene) of carbon containing or the carbon atom of volatilization are produced ion, quicken that with bias voltage it is impinged upon on the base material 1 and form DLC, see shown in Figure 4, PVD commonly used comprises arc process (Electric Arching), laser stripping plating method (Laser Ablation), sputtering method (Spattering Coating), and DLC also can utilize radio frequency that decomposing gas is deposited, and is called radio frequency chemical vapour deposition (CVD) (Radio Frequency ChemicalVapor Deposition).When penetrating the plating non-crystal diamond, if use low electricity slurry electric current or add that the electromagnetism chimney filter then can be plated to the even surface of atom level, applicable to mechanical with electric arc.When strengthening the electric current spraying plating, then can make DLC how produce the coarse structure of meter level, and can be used for photovoltaic.

Utilize the heat radiation diamond faster four times than copper, then the phonon (Phonon) with lattice vibration takes heat energy to the lower temperature place, and DLC but can take into account both simultaneously, promptly conducts heat with the metallic bond of graphite and the insulation key (covalent bond) of diamond.In addition, DLC more can convert the heat energy (atomic vibration) on surface to ultrared electromagnetic wave, (Black Body Radiation) directly flies to pass to airborne molecule with black body radiation, DLC not only can black body radiation, contained a large amount of diamond bond more helps the diffusion of heat in it, make the surface temperature of whole base material fin close, its radiance of the DLC of black matrix surpasses 90%, therefore its emitted heat energy can be than with the copper of area or aluminium more than big ten times, DLC thereby can synchrotron radiation quicken heat radiation.

On the commercial Application, because CCFL includes the harmful mercury of trace, industrial quarters is the backlight replacement CCFL of plan with light-emittingdiode LED.

From the above mentioned, be not difficult to find, bore combining of carbon-coating by graphite substrate with class, each is with the characteristic of high thermal conductivity, the surface radiating speed ratio common metal of DLC is more than high ten times, and has the characteristic of high strength, high rigidity, and it is coated on the graphite substrate surface, then can complement each other, reach the effect of efficiently radiates heat.

Claims

1, a kind of heat radiating material is characterized in that: this heat radiating material is a body with a graphite substrate, is coated with one deck class in the graphite substrate surface and bores carbon structure.

2, heat radiating material according to claim 1 is characterized in that: this graphite substrate is any in nature crystalline flake graphite, expanded graphite, the Delanium.

3, heat radiating material according to claim 1 is characterized in that: this graphite substrate comprises any in diamond micro mist, metal dust, palpus shape carbon fiber, carbon nanotube, vapor deposition based carbon fiber, carbon fiber, the carbon black.

4, heat radiating material according to claim 1 is characterized in that: the density of this graphite substrate is 0.02 to 2.35g/cm ³Between.

5, a kind of heat radiating material is characterized in that: this heat radiating material is body with the graphite substrate, and body contains the fiber of high thermal conductivity, and is coated with one deck class brill carbon structure in the graphite substrate surface.

6, heat radiating material according to claim 5 is characterized in that: the draw ratio of this fiber is between 1～5000.

7, heat radiating material according to claim 5 is characterized in that: the material of this fiber is any in metallic fiber, ceramic fibre, macromolecular fibre, the material with carbon element fiber.

8, heat radiating material according to claim 7 is characterized in that: this metallic fiber is any in copper, aluminium and the alloy thereof.

9, heat radiating material according to claim 7 is characterized in that: this ceramic fibre is any in carborundum, aluminium oxide, the high heat biography pottery.

10, heat radiating material according to claim 7 is characterized in that: this material with carbon element fiber is carbon fiber, graphite fibre, nano carbon tubes, how rice carbon ball, rice carbon any in protruding how.