Polymer and solder pillars for connecting chip and carrier

Abstract

A method of connecting chips to chip carriers, ceramic packages, etc. (package substrates) forms smaller than usual first solder balls and polymer pillars on the surface of a semiconductor chip and applies adhesive to the distal ends of the polymer pillars. The method also forms second solder balls, which are similar in size to the first solder balls, on the corresponding surface of the package substrate to which the chip will be attached. Then, the method positions the surface of the semiconductor chip next to the corresponding surface of the package substrate. The adhesive bonds the distal ends of the polymer pillars to the corresponding surface of the package substrate. The method heats the first solder balls and the second solder balls to join the first solder balls and the second solder balls into solder pillars.

1 . A structure comprising:
 a semiconductor chip;   a package substrate connected to said semiconductor chip;   polymer pillars positioned between and connecting said semiconductor chip and said package substrate; and   solder pillars positioned between and connecting said semiconductor chip and said package substrate.   
     
     
         2 . The structure according to  claim 1 , all the limitations of which are incorporated herein by reference, wherein said solder pillars have a shape and a size similar to that of said polymer pillars. 
     
     
         3 . The structure according to  claim 1 , all the limitations of which are incorporated herein by reference, wherein said solder pillars and said polymer pillars each have a first dimension between said semiconductor chip and said package substrate that is at least 2 times a second dimension that is perpendicular to said first dimension. 
     
     
         4 . The structure according to  claim 1 , all the limitations of which are incorporated herein by reference, wherein said solder pillars provide greater physical support between said semiconductor chip and said package substrate relative to said solder pillars. 
     
     
         5 . The structure according to  claim 1 , all the limitations of which are incorporated herein by reference, wherein said solder pillars lack lead. 
     
     
         6 . A structure comprising:
 a semiconductor chip;   a package substrate connected to said semiconductor chip;   polymer pillars positioned between and connecting said semiconductor chip and said package substrate; and   solder pillars positioned between and connecting said semiconductor chip and said package substrate,   wherein said polymer pillars comprise optical transmission media adapted to transmit optical signals between said semiconductor chip and said package substrate,   wherein said solder pillars comprise electrical transmission media adapted to transmit electrical signals between said semiconductor chip and said package substrate, and   wherein said solder pillars comprise two joined solder balls.   
     
     
         7 . The structure according to  claim 6 , all the limitations of which are incorporated herein by reference, wherein said solder pillars have a shape and a size similar to that of said polymer pillars. 
     
     
         8 . The structure according to  claim 6 , all the limitations of which are incorporated herein by reference, wherein said solder pillars and said polymer pillars each have a first dimension between said semiconductor chip and said package substrate that is at least 2 times a second dimension that is perpendicular to said first dimension. 
     
     
         9 . The structure according to  claim 6 , all the limitations of which are incorporated herein by reference, wherein said solder pillars provide greater physical support between said semiconductor chip and said package substrate relative to said solder pillars. 
     
     
         10 . The structure according to  claim 6 , all the limitations of which are incorporated herein by reference, wherein said solder pillars lack lead. 
     
     
         11 . A method comprising:
 forming first solder balls on a surface of a semiconductor chip;   forming polymer pillars on said surface of said semiconductor chip;   forming second solder balls on a corresponding surface of a package substrate;   positioning said surface of said semiconductor chip next to said corresponding surface of said package substrate such that said polymer pillars contact said corresponding surface of said package substrate and such that said first solder balls contact corresponding ones of said second solder balls; and   heating said first solder balls and said second solder balls to join said first solder balls and said second solder balls into solder pillars.   
     
     
         12 . The method according to  claim 11 , all the limitations of which are incorporated herein by reference, wherein said polymer pillars extend further from said surface of said semiconductor chip than said first solder balls. 
     
     
         13 . The method according to  claim 11 , all the limitations of which are incorporated herein by reference, wherein combined diameters of said first solder balls and said second solder balls is equal to or greater than a dimension that said polymer pillars extend from said surface of said semiconductor chip. 
     
     
         14 . The method according to  claim 11 , all the limitations of which are incorporated herein by reference, wherein said polymer pillars maintain relative positions of said surface of said integrated circuit chip and said corresponding surface of said package substrate during said heating of said first solder balls and said second solder balls. 
     
     
         15 . The method according to  claim 11 , all the limitations of which are incorporated herein by reference, wherein said heating comprises heating to a temperature at least equal to a melting point of said first solder balls and said second solder balls. 
     
     
         16 . A method comprising:
 forming first solder balls on a surface of a semiconductor chip;   forming polymer pillars on said surface of said semiconductor chip;   applying adhesive to distal ends of said polymer pillars, wherein said distal ends comprise ends of said polymer pillars that are furthest away said surface of said semiconductor chip;   forming second solder balls on a corresponding surface of a package substrate;   positioning said surface of said semiconductor chip next to said corresponding surface of said package substrate such that said distal ends of said polymer pillars contact said corresponding surface of said package substrate and such that said first solder balls contact corresponding ones of said second solder balls, wherein said adhesive bonds said distal ends of said polymer pillars to said corresponding surface of said package substrate; and   heating said first solder balls and said second solder balls to join said first solder balls and said second solder balls into solder pillars.   
     
     
         17 . The method according to  claim 16 , all the limitations of which are incorporated herein by reference, wherein said polymer pillars extend further from said surface of said semiconductor chip than said first solder balls to an extent such that said applying of said adhesive to said distal ends of said polymer pillars is performed without applying adhesive to said first solder balls. 
     
     
         18 . The method according to  claim 16 , all the limitations of which are incorporated herein by reference, wherein combined diameters of said first solder balls and said second solder balls is equal to or greater than a dimension that said polymer pillars extend from said surface of said semiconductor chip. 
     
     
         19 . The method according to  claim 16 , all the limitations of which are incorporated herein by reference, wherein said polymer pillars maintain relative positions of said surface of said integrated circuit chip and said corresponding surface of said package substrate during said heating of said first solder balls and said second solder balls. 
     
     
         20 . The method according to  claim 16 , all the limitations of which are incorporated herein by reference, wherein said heating comprises heating to a temperature at least equal to a melting point of said first solder balls and said second solder balls.