TWI477594B - Composites with high thermal conductivity - Google Patents

Description

Composite material with high thermal conductivity

The invention is a composite material with high thermal conductivity, in particular, a composite material with excellent thermal conductivity and good jointability, and can simultaneously serve as a high thermal conductivity composite for component assembly bonding and auxiliary electronic component heat dissipation.

With the rapid development of the electronics industry, various types of electronic products have increased the heat generated per unit area due to high speed, miniaturization and power increase. However, high heat flux density can cause deterioration of electronic products, shorten the life of products, and even The structure is damaged. Therefore, in order to maintain the stability and reliability of electronic products, heat must be effectively removed.

The usual method is to dissipate heat to the outside of the system. The known methods of heat transfer include heat conduction, heat convection and heat radiation. However, due to the problem of local hot spots of electronic components, the temperature distribution must be uniformed before the heat dissipation component is used. The heat is transferred to the surrounding environment, so whether it is a heat sink or a heat sink, such as a heat spreader, a heat sink fin, a heat pipe or a flat loop heat pipe, it must be closely adhered to the electronic component to avoid contact heat resistance at the gap on the interface. Therefore, the heat dissipating component cannot be effectively utilized. In order to eliminate the pores, voids or gaps between the interfaces that cause poor thermal conductivity, heat-dissipating pastes, heat-conductive patches, and the like are generally used to reduce the thermal resistance between the electronic components and the heat-dissipating components, thereby improving heat dissipation performance. Conventionally known thermal grease or polymer phase change thermal interface materials are combined with a polymer having better thermal conductivity by using a polymer material, but the polymer compound is susceptible to heat or exposure to ultraviolet light and loses cohesiveness, so attempts have been made to utilize Low melting point The alloy acts as a thermal interface material to overcome the problem of polymer aging, and this method has better thermal conductivity. However, the use of metal as a thermal interface material, although providing a high thermal conductivity, is generally not possible to form a close joint between the metal and the electronic component or the heat dissipating component, as disclosed in the Chinese Patent Publication No. 200822324. A metal thermal interface material with variable melting point temperature, which uses a low melting point phase change metal composed of a metal such as bismuth, indium, tin or gallium to make the metal thermal interface material have an initial hot melting temperature lower than 60 ° C and It does not contain toxic environmental elements, but such low melting point alloys are not easily wetted on aluminum or ceramics, and it is easy to form interface pores or gaps, which affects the heat dissipation effect.

Good thermal interface materials must have good thermal conductivity in addition to good wettability with the joints to effectively fill the pores on the interface to reduce the interface thermal resistance, and in use, due to the operation of the components. The temperature rises, so it is also necessary to have good bonding to avoid interface separation. As disclosed in Japanese Patent No. I344196, it is a metal thermal interface material suitable for being disposed between the interfaces of the integrated circuit bare crystal to the heat conduction path of the heat sink, wherein the metal thermal interface material has a through-hole structure inside and / or a sawtooth or wavy structure around. Although such a low melting point alloy can utilize the phase change during liquefaction to absorb thermal energy in a latent heat manner, it is necessary to suppress the liquid phase overflow problem, and the liquid phase and solid phase volume change of the alloy causes void formation and has a joint. Force, there must be other auxiliary locking or other interface bonding materials for the combination of electronic components and heat-dissipating components, which is cumbersome in composition.

Therefore, the present invention has been made in an effort to provide a composite material which has both good thermal conductivity and excellent bonding properties in order to facilitate the application of component mounting, such as heat dissipation and bonding between electronic components.

SUMMARY OF THE INVENTION A primary object of the present invention is to provide a composite material having high thermal conductivity which has excellent thermal conductivity and which can quickly derive the heat of the connected components.

A secondary object of the present invention is to provide a composite material having high thermal conductivity, which can be wet-bonded to form a tight bond with the interface of the connected component, eliminate voids or gaps, and reduce interface contact thermal resistance. Good jointability.

Another object of the present invention is to provide a composite material having high thermal conductivity which can prevent the electronic product from rapidly degrading due to high heat and can prolong the life of the product.

In order to achieve the above object, the present invention discloses a composite material having high thermal conductivity, comprising an active solder alloy and an inorganic high thermal conductive substrate; the active solder alloy comprising at least one alloy substrate and an active element. The inorganic high thermal conductive substrate is carbon fiber, carbon nanotube, graphite, tantalum carbide, aluminum nitride or cerium oxide in the form of powder, fiber or granule, and the inorganic high thermal conductive substrate is used for mixing the active soft Welding alloys to improve thermal conductivity.

10‧‧‧Heat components

20‧‧‧Composite material layer with high thermal conductivity

30‧‧‧Electronic components

First Figure: It is a schematic diagram of heat dissipation according to a preferred embodiment of the present invention.

In order to provide the Applicant with a better understanding and understanding of the features and advantages of the present invention, the preferred embodiments and the detailed description are to be construed as follows: The thermal conductivity is not good or can not be closely adhered to the surface of the heat generating or heat dissipating component, so that the heat conduction performance is lowered, the waste heat cannot be smoothly discharged, the property of the component is rapidly deteriorated, and the life is shortened. Therefore, the present invention designs the defect for the defect. A composite material with high thermal conductivity to achieve the goal of high thermal conductivity and bonding.

The composite material having high thermal conductivity of the present invention comprises an active solder alloy and an inorganic high thermal conductive substrate. Wherein, the active solder alloy comprises at least one alloy substrate and an active element additive, and the alloy substrate is selected from the group consisting of tin (Sn), indium (In), bismuth (Bi), and zinc ( Among Zn), one or several metals are composed of a substrate, and elements such as silver (Ag) and copper (Cu) may be added, and the active element is composed of titanium (Ti), rare earth element or magnesium (Mg). And other elements, the active solder alloy is mixed with the alloy substrate and the active element, and has the property of directly bonding the ceramic, and the high activity can also promote good metallurgical bonding; as for the inorganic high thermal conductive substrate, the shape thereof It can be in the form of powder, fiber or granules, and its material can be carbon fiber, carbon nanotube, graphite, tantalum carbide, aluminum nitride, cerium oxide or other metals with good thermal conductivity. The inorganic high thermal conductive substrate is mixed with the active solder alloy to form a composite material having high thermal conductivity of the present invention.

In one of the preferred embodiments of the present invention, the active solder alloy is used, wherein in the active element additive which affects the bonding property, titanium accounts for 0.5 to 10% by weight of the total active solder alloy, and the rare earth element It is 0.05~1% by weight.

Moreover, in the composite material having high thermal conductivity, the inorganic high thermal conductive substrate accounts for 5% to 50% of the total material volume. The method of mixing with the active solder alloy is to use a powder, fiber or granule which is fine in the inorganic high heat conductive substrate, and stir and mix the molten active solder alloy to uniformly mix the two.

The composite material with high thermal conductivity of the present invention can be obtained by mixing the materials disclosed above, and has good thermal conductivity and bonding property, and metallurgical bonding and ceramic material are generated for the contact interface by incorporating the active element additive. The high bonding property, supplemented by the inorganic high-heat-conducting substrate with high thermal conductivity, allows the interface between thermal energy and adhesion to be quickly exported from the heat-generating component to the heat-dissipating component.

Next, please refer to the first figure, which is a heat dissipation according to a preferred embodiment of the present invention. As shown in the figure, the composite material with high thermal conductivity of the present invention comprises a heat dissipating component 10, a composite material layer 20 having high thermal conductivity, and an electronic component 30 for heat dissipation applications.

In the heat dissipation diagram, the electronic component 30 is a part of the electronic product that generates heat, and a large amount of thermal energy generated during the work process needs to be derived by the heat dissipation component to prevent the accumulation of waste heat, thereby reducing the working efficiency of the electronic component and shortening the service life. The high thermal conductivity composite material layer 20 is applied between the heat dissipating component 10 and the interface of the electronic component 30, so that the thermal energy can smoothly pass through the composite material layer 20 having high thermal conductivity and reach the heat dissipating component. In this setting, the composite layer 20 having high thermal conductivity not only has the function of assisting the heat dissipation of the electronic component 30, but also has excellent bonding property, so that there is no gap between the electronic component 30 and the heat dissipation component 10 that affects heat dissipation. The contact thermal resistance is reduced, so that the heat dissipating component can be effectively utilized.

Through the operation of the composite material with high thermal conductivity, the combination of the electronic component and the heat dissipating component and the goal of reducing the thermal resistance of the interface contact can be simultaneously achieved, overcoming the shortcomings of the past that cannot solve the problem of poor adhesion or heat dissipation.

The above is only the preferred embodiment of the present invention, and is not intended to limit the scope of the present invention, and the variations, modifications, and modifications of the shapes, structures, features, and spirits described in the claims of the present invention. All should be included in the scope of the patent application of the present invention.

The invention is a novelty, progressive and available for industrial use, and should meet the requirements of the patent application stipulated in the Patent Law of China, and the invention patent application is filed according to law, and the prayer bureau will grant the patent as soon as possible. prayer.

10‧‧‧Heat components

20‧‧‧Composites with high thermal conductivity

30‧‧‧Electronic components

Claims (5)

A composite material having high thermal conductivity comprises: an inorganic high thermal conductive substrate mixed with a reactive solder alloy for improving thermal conductivity; wherein the active solder alloy can be bonded to a ceramic material, The invention comprises: an alloy substrate comprising tin, indium, antimony, zinc and one of any combination thereof; and an active element additive comprising magnesium, a combination of magnesium and titanium or magnesium and a rare earth element combination. The composite material having high thermal conductivity as described in claim 1, wherein the alloy substrate further comprises one of silver, copper, and any combination thereof. The composite material having high thermal conductivity as described in claim 1, wherein the inorganic high thermal conductive substrate component comprises carbon fiber, carbon nanotube, graphite, tantalum carbide, aluminum nitride, tantalum oxide and metal. One of the ethnic groups. The composite material having high thermal conductivity as described in claim 1, wherein the inorganic high thermal conductive substrate may be in the form of a powder, a fiber or a granule. The composite material having high thermal conductivity as described in claim 1, wherein the inorganic high thermal conductive substrate occupies a volume fraction of 5% to 50% of the composite material having high thermal conductivity.