Method of forming an electrical contact

Abstract

In a test system, a silicon interconnect is provided that can accommodate a packaged part, such as a Land Grid Array (LGA) package. The interconnect can be made by etching a silicon substrate to form projections therefrom; forming an insulation or passivation layer through deposition or growth; depositing a seed layer over the insulation layer; depositing a metal layer over the seed layer; and etching contact members from the seed and metal layers using a single mask step. In a preferred embodiment, the metal layer is coated with another metal layer that matches the metal of the packaged part's electrical communication nodes. In one embodiment, the contact surfaces of the silicon contact are plated in gold and are planar. Included within the scope of the current invention are at least one method of testing an LGA package and at least one method of allowing electrical communication with a packaged part.

1 . A process method for an electrical contact for a die having an electrical communication node, the electrical communication node having a known shape formed from a known material, the method comprising: 
 forming a support structure for forming a contact for the known shape of the electrical communication node of the die;    forming a portion of the support structure to have a shape for contacting a portion of the electrical communication node of the die;    forming an aluminum layer over a portion of the support structure formed to have a shape for contacting a portion of the electrical communication node of the die;    forming a zinc layer; and    forming a contact surface, the contact surface of the same material as the material of the electrical communication node of the die.    
   
   
       2 . The method in  claim 1 , further comprising forming the zinc layer after forming an aluminum layer and before forming a contact surface.  
   
   
       3 . The method in  claim 2 , further comprising forming a nickel layer after forming a zinc layer and before the forming a contact surface.  
   
   
       4 . The method in  claim 3 , wherein forming an aluminum layer comprises sputtering aluminum over the support structure.  
   
   
       5 . The method in  claim 4 , wherein forming a zinc layer comprises exposing the aluminum layer to a zincate solution.  
   
   
       6 . The method in  claim 5 , wherein forming a nickel layer comprises exposing the zinc layer to a nickel solution.  
   
   
       7 . The method in  claim 6 , wherein the forming a contact surface comprises providing a selection of one of a gold surface and a palladium surface.  
   
   
       8 . The method in  claim 1 , wherein the forming a contact surface comprises forming a contact surface essentially matching the shape of the electrical communication node of the die.  
   
   
       9 . The method in  claim 8 , wherein forming a contact surface comprises forming an essentially flat contact surface.  
   
   
       10 . A process method for an electrical contact for a die having an electrical, the electrical node having a known shape formed from a known material, the method comprising: 
 forming a support structure for forming a contact for the known shape of the electrical node of the die;    forming a portion of the support structure to have a shape for contacting a portion of the electrical node of the die;    forming an aluminum layer over a portion of the support structure formed to have a shape for contacting a portion of the electrical node of the die;    forming a zinc layer; and    forming a contact surface, the contact surface of the same material as the material of the electrical node of the die.    
   
   
       11 . The method in  claim 10 , further comprising forming the zinc layer after forming an aluminum layer and before forming a contact surface.  
   
   
       12 . The method in  claim 11 , further comprising forming a nickel layer after forming a zinc layer and before the forming a contact surface.  
   
   
       13 . The method in  claim 12 , wherein forming an aluminum layer comprises sputtering aluminum over the support structure.  
   
   
       14 . The method in  claim 13 , wherein forming a zinc layer comprises exposing the aluminum layer to a zincate solution.  
   
   
       15 . The method in  claim 14 , wherein forming a nickel layer comprises exposing the zinc layer to a nickel solution.  
   
   
       16 . The method in  claim 15 , wherein the forming a contact surface comprises providing a selection of one of a gold surface and a palladium surface.  
   
   
       17 . The method in  claim 10 , wherein the forming a contact surface comprises forming a contact surface essentially matching the shape of the electrical node of the die.  
   
   
       18 . The method in  claim 17 , wherein forming a contact surface comprises forming an essentially flat contact surface.  
   
   
       19 . A process method for an electrical contact for a die having a node, the node having a known shape formed from a known material, the method comprising: 
 forming a support structure for forming a contact for the known shape of the node of the die;    forming a portion of the support structure to have a shape for contacting a portion of the node of the die;    forming an aluminum layer over a portion of the support structure formed to have a shape for contacting a portion of the node of the die;    forming a zinc layer; and    forming a contact surface, the contact surface of the same material as the material of the node of the die.    
   
   
       20 . The method in  claim 19 , further comprising: 
 forming the zinc layer after forming an aluminum layer and before forming a contact surface:    forming a nickel layer after forming a zinc layer and before the forming a contact surface;    forming an aluminum layer comprises sputtering aluminum over the support structure;    forming a zinc layer comprises exposing the aluminum layer to a zincate solution;    forming a nickel layer comprises exposing the zinc layer to a nickel solution;    forming a contact surface comprises providing a selection of one of a gold surface and a palladium surface;    forming a contact surface comprises forming a contact surface essentially matching the shape of the electrical communication node of the die; and    forming a contact surface comprises forming an essentially flat contact surface.