Method for forming an electronic assembly

Abstract

An overmolded electronic assembly having an electromagnetic interference shield, in the form of a thin metal film or foil, coupled to the top of or within an overmolded body. The shield effectively reduces the amount of electromagnetic interference (“EMI”) emissions from penetrating within the assembly to the circuit board without substantially increasing the cost of the unit. Thus, an electronic assembly having improved vibration, moisture, and EMI emission resistance is achieved as compared with traditional overmolded or metal assemblies. Further, because the shield can be formed on the electronic assembly in one continuous processing step, a substantial savings in time and cost for the manufacturing process is also realized.

1 . A method for forming an overmolded electronic assembly having improved EMI shielding comprising: 
 providing a heatsink and a circuit board;    forming an overmolded body;    thermal or kinetic spraying a thin metal film onto said overmolded body, said thin metal film selected from the group consisting of a thin tin film, a thin zinc film, a thin tin and antimony alloy film, and a thin silicon and bronze alloy film;    grounding said thin metal film to a railplate of said heatsink; and    air drying said thin metal film onto said overmolded body to form an overmolded housing assembly, wherein said thin metal film has sufficient thickness to provide electromagnetic interference shielding to said circuit board.    
   
   
       2 . (canceled)  
   
   
       3 . The method of  claim 1 , wherein thermal spraying a thin metal film onto said overmolded body comprises thermal spraying a thin metal film onto said overmolded body, wherein the thickness of said thin metal film on said overmolded body is approximately 0.002 and 0.004 inches thick.  
   
   
       4 . (canceled)  
   
   
       5 . (canceled)