Heat sink and method for making same

Abstract

A heat sink ( 5 ) for dissipating heat from an electronic component includes a base ( 50 ), and a plurality of fins ( 52 ) formed on the base. The base and the plurality of fins are integrally formed by sintering one or two metallic nano-powders. Since the heat sink is integrally formed by sintering, any thermal resistance between the base and the fins is minimized. In addition, because the base and the fins of the heat sink are all made from one or more metallic nano-powders having good thermal conductivity, a surface area of the heat sink is larger than that of a comparable heat sink made by extrusion. Therefore, a heat transfer efficiency of the heat sink is improved.

1 . A heat sink comprising: 
 a base; and    a plurality of fins extending from the base;    wherein, the base and the fins are integrally formed, and comprise one or more sintered metallic nano-powders.    
     
     
         2 . The heat sink as described in  claim 1 , wherein the base and the fins are made from a same sintered metallic nano-powder.  
     
     
         3 . The heat sink as described in  claim 1 , wherein the base and the fins are made from different sintered metallic nano-powders.  
     
     
         4 . The heat sink as described in  claim 1 , wherein the one or more metallic nano-powders is/are selected from the group consisting of gold, silver, copper, aluminum, and any alloy thereof.  
     
     
         5 . The heat sink as described in  claim 4 , wherein a grain size of the one or more metallic nano-powders is in the range from 1 to 99 nanometers.  
     
     
         6 . The heat sink as described in  claim 1 , further comprising nanomaterials formed thereon, for improving the heat exchange performance of the heat sink.  
     
     
         7 . The heat sink as described in  claim 6 , wherein the nanomaterials are carbon nanotubes or carbon nanocapsules.  
     
     
         8 . The heat sink as described in  claim 7 , wherein the carbon nanotubes are formed on a surface of the base distalmost from the fins.  
     
     
         9 . The heat sink as described in  claim 8 , wherein the carbon nanotubes are substantially parallel to each other, and are substantially perpendicular to the base.  
     
     
         10 . A method for making a heat sink, comprising the following steps: 
 (a) providing a mold having a predetermined shape according to a desired shape of the heat sink, the mold comprising a first portion corresponding to a base of the heat sink and a second portion adjacent the first portion corresponding to fins of the heat sink;    (b) putting one or more metallic nano-powders in the first and second portions of the mold respectively; and    (c) sintering the metallic nano-powders within the mold in an inert gas environment to thereby form the heat sink with the fins integrally formed on the base.    
     
     
         11 . The method as described in  claim 10 , wherein a same metallic nano-powder is put in the first and second portions of the mold.  
     
     
         12 . The method as described in  claim 10 , wherein the metallic nano-powders put in the first and second portions of the mold are different.  
     
     
         13 . The method as described in  claim 10 , wherein the one or more metallic nano-powders is/are selected from the group consisting of gold, silver, copper, aluminum, and any alloy thereof.  
     
     
         14 . The method as described in  claim 10 , wherein a grain size of the one or more metallic nano-powders is in the range from 1 to 99 nanometers.  
     
     
         15 . The method as described in  claim 10 , further comprising the step of: 
 (d) forming nanomaterials on the heat sink.    
     
     
         16 . The method as described in  claim 15 , wherein the nanomaterials are formed on the fins.  
     
     
         17 . The method as described in  claim 15 , wherein the nanomaterials are carbon nanotubes, and the carbon nanotubes are formed on a surface of the base distalmost from the fins.  
     
     
         18 . A method for making a heat dissipating device, comprising the following steps: 
 preparing a mold providing a predetermined shape of said heat dissipating therein;    depositing at least one kind of metallic nano-powder within said mold to shape into said heat dissipating device; and    sintering said at least one kind of metallic nano-powder within said mold to form said heat dissipating device as a whole.    
     
     
         19 . The method as described in  claim 18 , wherein said heat dissipating device has a base and fins, and said fins are made of said sintered at least one kind of metallic nano-power and said base is made of another kind of metallic nano-powder.  
     
     
         20 . The method as described in  claim 18 , further comprising the step of attaching carbon nanotubes to at least one side of said heat dissipating device to enhance heat transmission thereof.