Metallurgical clamshell methods for micro land grid array fabrication

Abstract

A structure and method for manufacturing the same for manufacturing a contact structure for microelectronics manufacturing including the steps of forming first and second metal sheets to form a plurality of outwardly extending bump each defining a cavity. Symmetrically mating the first and second metal sheets in opposing relation to each other to form upper and lower bumps each defining an enclosure therebetween wherein the mated first and second sheets form a contact structure. Coating the contact structure with an insulating material, and fabricating helix shaped contacts from upper and lower bumps. The helix shaped contacts having first and second portions being in mirror image relationship to each other.

What is claimed is: 
     
         1 . A method for manufacturing a contact structure for microelectronics manufacturing, comprising:
 forming first and second metal sheets to form a plurality of outwardly extending bumps each defining a cavity;   positioning an insulating carrier between the first and second metal sheets; passing a conductive via through the insulating carrier;   symmetrically mating the first and second metal sheets to opposing sides of the insulating carrier in opposing relation to each other to form upper and lower bumps each defining an enclosure therebetween, the mated first and second sheets forming a contact structure; and   fabricating helix shaped contacts from the upper and lower bumps by applying a photoresist to the upper and lower bumps, exposing the photoresist on both the upper and lower bumps by rotating and tilting the upper and lower bumps to provide a patterned photoresist, and etching the upper and lower bumps to the patterned photoresist forming the helix shaped contacts having first and second portions being in opposing relationship to each other having the insulating carrier therebetween.   
     
     
         2 . The method according to  claim 1 , wherein the exposing the photoresist includes rotating and tilting the upper and lower bumps simultaneously to provide a uniform exposure of the photoresist to provide the patterned photoresist. 
     
     
         3 . The method according to  claim 1 , wherein the first and second portions of the helix shaped contacts are in opposing mirror image relationship to each other. 
     
     
         4 . The method of  claim 1 , wherein the bumps are frustoconically shaped. 
     
     
         5 . The method of  claim 1 , further comprising applying a plurality of conductive metal coatings to the bumps. 
     
     
         6 . The method of  claim 1 , further comprising:
 positioning at least one contact point on each of the contacts between a pair of semiconductor substrates including electrically conductive members; and   positioning the at least one contact point on each of the contacts to electrically communicate with respective electrically conductive members to form an electrically conductive package.   
     
     
         7 . The method of  claim 1 , further comprising:
 compressing the contacts between the semiconductor substrates such that the contacts twist on the electrically conductive members during the compression.   
     
     
         8 . A leaf spring contact structure for microelectronics, comprising:
 first and second metal sheets in opposing relation to each other, the first and second metal sheets respectively forming first and second arrays of bumps; and   third and fourth metal sheets positioned over, respectively, the first and second metal sheets;   the third metal sheet forming a third array of bumps, each of the bumps of the third array forming a corresponding cavity, the third metal sheet being located over the first metal sheet, in a nested relation therewith;   the fourth metal sheet forming a fourth array of bumps, each of the bumps of the fourth array forming a corresponding cavity, the fourth metal sheet being located over the second metal sheet, in a nested relation therewith; and wherein:   patterns are formed in the bumps of the first, second, third and fourth metal sheets to form a contact structure having arrays of contacts and providing a leaf spring action with independent moving layers;   the bumps of the first and third metal sheets form an array of first helically shaped contacts, each of the first helically shaped contacts including a base and a spiral portion extending outward from said base; and   the bumps of the second and fourth metal sheets form an array of second helically shaped contacts, each of the second helically shaped contacts including a base and a spiral portion extending outward from the base of the contact and away from the first and third metal sheets.   
     
     
         9 . The structure of  claim 8 , wherein the first and third metal sheets are mated with the second and fourth metal sheets to form a combined structure having a mid-plane. 
     
     
         10 . The structure of  claim 9 , wherein the bases of the first helically shaped contacts are adjacent said mid-plane and on a first side thereof. 
     
     
         11 . The structure of  claim 10 , wherein the bases of the second helically shaped contacts are adjacent the mid-plane and on a second side thereof, opposites said first side. 
     
     
         12 . The structure of  claim 8 , wherein each of the first helically shaped contacts extends outward in a first circular direction, and each of the second helically shaped contacts extend outward in a second circular direction, opposite to said first circular direction. 
     
     
         13 . The structure of  claim 8 , wherein each of the first and second helically shaped contacts is symmetrical about a vertical axis bisecting said each contact. 
     
     
         14 . The structure of  claim 8 , wherein the first, second, third and fourth metal sheets move radially outward with respect to a vertical axis passing through the upper and lower contact bumps. 
     
     
         15 . A method of manufacturing a leaf spring contact structure for microelectronics, comprising:
 mating first and second metal sheets in opposing relation to each other, the first and second metal sheets respectively forming first and second arrays of bumps; and   positioning third and fourth metal sheets over, respectively, the first and second metal sheets;   forming a third array of bumps in the third metal sheet, each of the bumps of the third array forming a corresponding cavity, the third metal sheet being located over the first metal sheet, in a nested relation therewith; and   forming a fourth array of bumps in the fourth metal sheet, each of the bumps of the fourth array forming a corresponding cavity, the fourth metal sheet being located over the second metal sheet, in a nested relation therewith; and wherein:   patterns are formed in the bumps of the first, second, third and fourth metal sheets to form a contact structure having arrays of contacts and providing a leaf spring action with independent moving layers; and wherein:   the bumps of the first and third metal sheets form an array of first helically shaped contacts, each of the first helically shaped contacts including a base and a spiral portion extending outward from said base; and   the bumps of the second and fourth metal sheets form an array of second helically shaped contacts, each of the second helically shaped contacts including a base and a spiral portion extending outward from the base of the contact and away from the first and third metal sheets.   
     
     
         16 . The method of  claim 15 , further comprising: mating the first and third metal sheets with the second and fourth metal sheets to form a combined structure having a mid-plane. 
     
     
         17 . The method of  claim 16 , wherein the bases of the first helically shaped contacts are adjacent said mid-plane and on a first side thereof. 
     
     
         18 . The method of  claim 17 , wherein the bases of the second helically shaped contacts are adjacent the mid-plane and on a second side thereof, opposites said first side. 
     
     
         19 . The method of  claim 18 , wherein each of the first helically shaped contacts extends outward in a first circular direction, and each of the second helically shaped contacts extend outward in a second circular direction, opposite to said first circular direction. 
     
     
         20 . The method of  claim 15 , wherein each of the first and second helically shaped contacts is symmetrical about a vertical axis bisecting said each contact.