TWM455330U - Porous ceramics heat sink - Google Patents

Description

Porous ceramic heat sink

This creation relates to a porous ceramic heat sink, especially a designer who uses the heat convection formed by the hot and cold air in the through-hole to quickly dissipate heat.

According to the current market, copper and aluminum heat sinks are mainly used as heat dissipation substrates for 3C products and LED products, and the high thermal conductivity of copper and aluminum is required to achieve rapid heat dissipation; however, copper and aluminum themselves are conductors, which usually must An insulating layer is used to avoid short circuit, but the thermal conductivity of the insulating layer is only 0.2~0.5W/mK, which seriously affects the heat conduction and heat dissipation effects of the copper and aluminum heat sinks, and has heat resistance problems.

After pressing, although some ceramic heat sinks have entered the market, such as aluminum nitride ceramic heat sinks, tantalum carbide ceramic heat sinks and ordinary 95% alumina ceramics, etc., although the thermal conductivity of aluminum nitride is very high, but the price It is expensive and easily hydrolyzed to form Al(OH)3 after moisture absorption, which causes the thermal conductivity of the aluminum nitride ceramic heat sink to be low, and the thermal conductivity is not exerted. The heat dissipation performance of the silicon carbide ceramic heat sink cannot meet the demand due to sintering difficulty; The type 95% alumina ceramic may cause the heat dissipation area to be too low due to the dense structure, or the heat dissipation performance may be lowered due to the unreasonable microstructure, or the heat dissipation effect may not be met because the microstructure and convection mechanism are not well understood.

The main purpose of this creation is to provide a porous ceramic heat sink with improved heat dissipation and low cost.

In order to achieve the above-mentioned effects, the structural features of the present invention are prepared by mixing at least a pore-forming agent and a binder with a metal compound having a high thermal conductivity and a high insulating property with a particle diameter of 20 to 100 μm. During the preparation process, the depletion disappears and the porous ceramic fin is in the form of a layered structure and is formed with minute holes, and the micro holes are staggered through holes.

Further, the porous ceramic fin has a thickness of between 0.5 and 2 mm, and the microchannel has a radius of between 600 and 8000 nm. Further, the porous ceramic fin further has a heat conductive layer having a thickness of between 0.02 and 0.08 mm. In addition, the porous ceramic heat sink is further mixed with a chemical agent such as a flux, a modifier, a reinforcing agent, a dispersing agent, a releasing agent, a flocculating agent, a softening agent, an antifoaming agent or a plasticizer. Furthermore, the metal compound is selected from the group consisting of alumina, aluminum nitride, cerium oxide or a combination of the foregoing metal compounds; the pore forming agent is selected from the group consisting of flour, rice flour, petroleum coke, starch, bamboo charcoal, charcoal, dextrin, sawdust, and poly Ethylene glycol, PMMA, PS, carbon black, wheat flour, phenolic resin, foamable resin, foamed foamed resin, polymethyl methacrylate, polyethylene terephthalate or the aforementioned pores a combination of agents; the binder is selected from the group consisting of sodium carboxymethylcellulose, hydroxymethylcellulose, polyvinyl alcohol, sodium citrate or a combination of the foregoing; the flux is selected from the group consisting of tetrabutyl titanate and n-decanoic acid. Ethyl ester, titanium oxide or a combination of the foregoing flux; the modifier is polyvinyl alcohol; the reinforcing agent is methyl cellulose; the dispersing agent is selected from the group consisting of polyvinyl alcohol, phenolic resin, foaming resin or the aforementioned dispersing agent Combining; the mold release agent is oleic acid; the flocculating agent is selected from the group consisting of magnesium sulfate, copper sulfate or a combination of the foregoing flocculating agents; the antifoaming agent is selected from the group consisting of natural oils, fats or combinations of the aforementioned antifoaming agents; Phthalates.

First, please refer to "Fig. 1" and "Fig. 2". The porous ceramic heat sink 10 of the present invention is a mixture of a metal compound having a high thermal conductivity and a high insulating property and having a particle diameter of 20 to 100 μm. The pore-forming agent and the binder are prepared by molding into a green body, drying and firing, and the prepared porous ceramic heat sink 10 preferably has a thickness of 0.5 to 2 mm. During the preparation process, the porous ceramic heat sink 10 is formed with a micro-channel 11 having a radius of between 600 and 8000 nm, thereby increasing the contact heat-dissipating area between the porous ceramic heat sink 10 and the air; Wherein, more than 95% of the formed micro-channels 11 are through-hole channels, so that the hot and cold air in the through-holes can form heat convection, and heat is immediately transferred to the outside of the porous ceramic heat sink 10 to maintain the porous ceramic heat sink 10 At a lower temperature; in addition, since the intermetallic compound is in a neck-like (point-like) sintering state, the porous ceramic fin 10 is in the form of a layered structure and the micro-channel 11 is a cross-flow structure. Again, the porous pottery The porcelain fin 10 further adheres to the heat conductive layer 12, and the thickness of the heat conductive layer 12 is preferably between 0.02 and 0.08 mm.

Further, the metal compound is selected from the group consisting of alumina having high thermal conductivity and high insulation, aluminum nitride, cerium oxide or a combination of the foregoing metal compounds. Further, in order to control the porosity and the pore size of the micropores 11 formed by the porous ceramic fins 10, the pore former is selected from the group consisting of flour, rice flour, petroleum coke, starch, bamboo charcoal, charcoal, dextrin, sawdust, and polyethylene glycol. , PMMA, PS, carbon black, wheat flour, phenolic resin, foamable resin, foamed foamed resin, polymethyl methacrylate, polyethylene terephthalate or a combination of the foregoing pore formers . In addition, in order to make the mixing of the raw material particles have better bonding, lower the firing temperature, increase the structural strength, and more easily release the mold, the flux, the modifier, the reinforcing agent, the dispersing agent, and the deodorizer may be appropriately further mixed. a chemical agent such as a molding agent, a flocculating agent, a softening agent, an antifoaming agent or a plasticizer; the bonding agent is selected from the group consisting of sodium hydroxymethylcellulose, hydroxymethylcellulose, polyvinyl alcohol, sodium citrate or the aforementioned binder a combination; the flux is selected from the group consisting of tetrabutyl titanate, ethyl orthosilicate, titanium oxide or a combination of the foregoing flux; the modifier is polyvinyl alcohol; the reinforcing agent is methyl cellulose; the dispersant is selected From a combination of polyvinyl alcohol, phenolic resin, foamed resin or the aforementioned dispersing agent; the releasing agent is oleic acid; the flocculating agent is selected from the group consisting of magnesium sulfate, copper sulfate or a combination of the foregoing flocculating agents; the antifoaming agent is selected from natural a combination of grease, rouge or the aforementioned antifoaming agent; the plasticizer is a phthalate.

Based on the composition of the present invention, there is no limitation on the molding method of the present invention, and the optimum molding method can be selected according to the existing conditions; for example, 100 parts by mass of the mixed alumina raw material, 8 to 24 parts by mass of the pore forming agent, and 3.2 to 10.5 of the bonding agent. 2 parts by weight to 8.4 parts by mass of the cosolvent, 1.5 to 6.4 parts by mass of the modifier, 2.1 to 5.6 parts by mass of the reinforcing agent, 2.1 to 3.3 parts by mass of the dispersing agent, 0.8 to 2.4 parts by mass of the flocculating agent, and 0.3 to 0.5 mass of the antifoaming agent. After the portion and the plasticizer are 0.7 to 1.3 parts by mass, the green body is produced by an isostatic pressing or a tape casting process. In the green firing process, the center temperature of the blank is determined by the amount of pore former added. Because the temperature of the firing atmosphere increases, heat cannot be quickly transferred to the center of the body. When it is high enough, the pore former can be burned to release heat, accelerate the rise of the center temperature of the body, and reduce the difference between the center temperature and the temperature of the firing atmosphere; however, when the amount of the pore former is too small, the porosity is caused on the one hand. Not enough, on the other hand, the center temperature of the blank is much lower than the temperature of the firing atmosphere, causing the body to crack; but when the amount of the pore-forming agent is too large, the body may collapse during firing, or due to the center of the body The temperature is much higher than the temperature of the firing atmosphere, causing the inconsistent firing shrinkage to cause cracking of the green body. Therefore, the micro-cavity formed by the porous ceramic heat sink of the present invention is a through-hole hole, so that the heat convection formed by the hot and cold air in the through-hole hole can be quickly dissipated, and the material and processing cost are low. It has the effect of improving heat dissipation and low cost. [00010] In summary, the structure revealed by this creation is unprecedented, and it can achieve the improvement of efficacy, and it can be used for industrial utilization, fully complying with the new patent requirements, and praying for the patents issued by the bureau. Inspire innovation, no sense of morality. [00011] However, the above-mentioned drawings and descriptions are only preferred embodiments of the present invention. Those skilled in the art who are familiar with the art, the modifications or equivalent changes made in the spirit of the case should still include the patent application in this case. Within the scope.

【00013】
10‧‧‧Porous ceramic heat sink
11‧‧‧ tiny holes
12‧‧‧thermal layer

[00012] FIG. 1 is a schematic structural view of a porous ceramic heat sink of the present invention. Figure 2 is a scanning electron micrograph of the porous ceramic heat sink of the present invention.

10‧‧‧Porous ceramic heat sink

11‧‧‧ tiny holes

12‧‧‧thermal layer

Claims (5)

A porous ceramic heat sink prepared by mixing at least a metal compound having a high thermal conductivity and a high insulating property with a pore-forming agent and a binder at a particle diameter of 20 to 100 μm, and the pore-forming agent is prepared in the preparation process. The depletion disappears, causing the porous ceramic heat sink to be in the form of a layered structure and formed with minute pores, and the minute pores are via holes that are alternately connected. The porous ceramic heat sink of claim 1, wherein the porous ceramic heat sink has a thickness of between 0.5 and 2 mm, and the microchannel has a radius of between 600 and 8000 nm. The porous ceramic heat sink of claim 1 or 2, wherein the porous ceramic heat sink further adheres to a heat conductive layer having a thickness of between 0.02 and 0.08 mm. The porous ceramic heat sink of claim 3, wherein the porous ceramic heat sink is further mixed with a flux, a modifier, a reinforcing agent, a dispersing agent, a releasing agent, a flocculating agent, a softening agent, an antifoaming agent or a plasticizer, etc. Chemical additives. The porous ceramic heat sink of claim 4, wherein the metal compound is selected from the group consisting of alumina, aluminum nitride, cerium oxide or a combination of the foregoing metal compounds; the pore forming agent is selected from the group consisting of flour, rice flour, petroleum coke, starch, and bamboo charcoal. , charcoal, dextrin, sawdust, polyethylene glycol, PMMA, PS, carbon black, wheat flour, phenolic resin, foamable resin, foamed foamed resin, polymethyl methacrylate, poly-p-phenylene a combination of ethylene glycol formate or the aforementioned pore former; the binder is selected from the group consisting of sodium carboxymethylcellulose, hydroxymethylcellulose, polyvinyl alcohol, sodium citrate or a combination of the foregoing; the flux is selected from the group consisting of a combination of tetrabutyl titanate, ethyl orthosilicate, titanium oxide or the aforementioned flux; the modifier is polyvinyl alcohol; the reinforcing agent is methyl cellulose; the dispersant is selected from the group consisting of polyvinyl alcohol and phenolic resin a foaming resin or a combination of the foregoing dispersing agents; the releasing agent is oleic acid; the flocculating agent is selected from the group consisting of magnesium sulfate, copper sulfate or a combination of the foregoing flocculating agents; the antifoaming agent is selected from the group consisting of natural oils, fats, or the aforementioned a combination of foaming agents; the plasticizer is a phthalate.