Methods for manufacturing heat sink having relatively high aspects ratio thereof

Abstract

Methods for manufacturing a heat sink having a central cavity, a taper core, a plurality of fins and a base plate integrally formed with the taper core and the fins are provided. The first proposed method includes the steps of: (a) making a die having a relatively high surface hardness, a specific inner hardness, a specific surface friction and a specific toughness so as to stand a relatively high pressure and achieve a relatively high aspect ratio of the heat sink; (b) putting a material into the die; (c) pressing the material with the relatively high pressure to form the heat sink integrally such that the heat sink would have a relatively high material crystal density; and (d) removing the heat sink from the die.

1 . A method for manufacturing a heat sink having a central cavity, a taper core, a plurality of fins and a base plate integrally formed with said taper core and said fins, comprising the steps of:
 ( a ) making a die having a relatively high surface hardness, a specific inner hardness, a specific surface friction and a specific toughness so as to stand a relatively high pressure and achieve a relatively high aspect ratio of said heat sink;   ( b ) putting a material into said die;   (c) pressing said material with said relatively high pressure to form said heat sink integrally such that said heat sink would have a relatively high material crystal density; and   (d) removing said heat sink from said die.   
   
   
       2 . The method according to  claim 1 , wherein said relatively high surface hardness, said specific inner hardness, said specific surface friction and said specific toughness are achieved through a specific tooling procedure comprising: a specific heat treating procedure, a specific polishing procedure and a specific coating procedure. 
   
   
       3 . The method according to  claim 2 , wherein said specific coating procedure is employed to coat a specific alloy of titanium and nickel on said die. 
   
   
       4 . The method according to  claim 2 , wherein said specific inner hardness is within a range of 50 HRC (Hardness: Rockwell C Scale) to 70 HRC. 
   
   
       5 . The method according to  claim 2 , wherein said relatively high aspect ratio of said heat sink is one of a ratio of a height of one of said fins to a distance between two neighboring ones of said fins and a ratio of said height to a thickness of one of said fins, said relatively high aspect ratio of said heat sink is equal to 100 preferably, a maximum value of said height is decided based at least in part on said specific surface friction, and a minimum value of one of said distance and said thickness is decided based at least in part on said relatively high surface hardness, said specific inner hardness and said specific toughness. 
   
   
       6 . The method according to  claim 1 , wherein said base plate contacts a heat source. 
   
   
       7 . The method according to  claim 6  further comprising a step of:
 (e) forming a plurality of holes on said base plate, wherein each of said holes is employed for receiving a standoff.   
   
   
       8 . The method according to  claim 7 , wherein said base plate further comprises a first side, a second side and a pedestal, said pedestal is integrally formed on said first side of said base plate, said taper core is integrally formed on said second side of said base plate, and said step (e) further comprises a step of: (e1) machining said base plate into said pedestal. 
   
   
       9 . The method according to  claim 8 , wherein said pedestal is employed for contacting said heat source. 
   
   
       10 . A method for manufacturing a heat sink having a central cavity, a taper core, a plurality of fins and a base plate integrally formed with said taper core and said fins, comprising the steps of:
 ( a ) making a die having a relatively high surface hardness, a specific inner hardness, a specific surface friction and a specific toughness so as to stand a relatively high pressure and achieve a relatively high aspect ratio of said heat sink;   ( b ) putting a main material having a positioning cavity into said die;   (c) placing a relatively high conductivity material into said positioning cavity;   (d) pressing said main material and said relatively high conductivity material with said relatively high pressure to form said heat sink integrally such that said heat sink would have a relatively high material crystal density, wherein said relatively high conductivity material forms a central part of said base plate, and said main material forms a surrounding part of said base plate; and   (e) removing said heat sink from said die.   
   
   
       11 . The method according to  claim 10  further comprising a step of:
 (f) forming a plurality of holes on said base plate, wherein each of said holes is employed for receiving a standoff.   
   
   
       12 . The method according to  claim 10 , wherein said base plate further comprises a pedestal integrally formed on said base plate. 
   
   
       13 . The method according to  claim 12 , wherein said step (f) further comprises a step of:
 (f1) machining said base plate into said pedestal.   
   
   
       14 . The method according to  claim 10 , wherein said positioning cavity is employed for positioning said relatively high conductivity material. 
   
   
       15 . The method according to  claim 10 , wherein said relatively high conductivity material has a thermal conductivity greater than that of said main material.