Device for interconnecting integrated circuit packages to circuit boards

Abstract

A novel and improved device for interconnecting an integrated circuit package to a circuit board is presented. In accordance with the present invention an integrated circuit package having an central area devoid of surface contacts is positioned over a resilient or compressible connector system. The compressible connector includes an opening about its center which corresponds to the central area on the integrated circuit package. A component is mounted on the circuit board within the opening of the compressible connector between the integrated circuit package and the circuit board.

What is claimed is: 
     
       1. An electronic subassembly comprising: an integrated circuit (IC) package, said IC package comprising a land grid array package, said land grid array package having an array of contacts on one surface thereof surrounding a contact free area, at least one of said contacts being a first contact, said first contact being receptive to a first voltage level, at least one other of said contacts being a second contact, said second contact being receptive to a second voltage level;   circuit board means having a plurality of pads, an array of which corresponds to said array of contacts of said land grid array package, at least one of said pads being a first pad, said at least one first pad corresponding to said at least one first contact, said first pad being electrically connected to at least one second pad and having said first voltage level thereon, at least one other of said pads being a third pad, said at least one third pad corresponding to said at least one second contact, said third pad being electrically connected to at least one fourth pad and having said second voltage level thereon, said second and fourth pads being disposed at an area on said circuit board means corresponding to said contact free area of said land grid array package;   first compressible connector means sandwiched between said IC package and said circuit board means, said connector means electrically and mechanically interconnecting said IC package to said circuit board means, said first compressible connector means including an opening therethrough, said opening being disposed under said contact free area of said IC package; and   a decoupling capacitor disposed in said opening and connected to said circuit board means, said decoupling capacitor providing decoupling capacitance between said first and second voltage levels on said land grid array package, said decoupling capacitor being in communication with said second and fourth pads on said circuit board means.   
     
     
       2. The apparatus of claim 1 wherein said first compressible connector means comprises: a first electrically non-conductive support member having an array of apertures therethrough . .said array of apertures corresponding to said array of contacts of said land grid array package.!. said first support member comprising resilient elastomeric foam material, said first support member having support surfaces to be respectively opposed to the surfaces of said circuit board means and said land grid array package and being adapted to be compressed by urging said circuit board means and said land grid array package together; and   a first plurality of bodily-rotatable, electrically conductive interconnect elements, each comprising a body extending generally in the direction of the thickness of the resilient elastomeric foam support member and tab portions projecting angularly from the respective ends of said body, each of said first elements defining a pair of engagement surfaces disposed to engage respective ones of corresponding said pads of said circuit board means at one end and to engage respective ones of corresponding said contacts of said land grid array package at the other end, a line projected through said engagement surfaces being disposed at an initial acute angle to the direction of thickness of said first support member, and said tab portions defining engagement surfaces disposed at least closely in opposition to said support surfaces of said first support member to engage upon said support surfaces during bodily rotation of said first interconnect element to locally compress the elastomeric foam of said first support member, whereby, when said first compressible connector means is disposed between said circuit board means and said land grid array package in a clamped together relationship with said first interconnect elements in registry with said corresponding pads of said circuit board means and said corresponding contacts of said land grid array package, and with said first interconnect elements rotated bodily as a result of said clamping so that said line projected through said engagement surfaces of each element lies at an acute angle resiliently supported by said elastomeric foam to bear with force upon said pads of said circuit board means and said contacts of said land grid array package, and said voids of . .said.!. elastomeric foam of said first support member serve locally to accommodate bodily rotation of said first interconnect elements in a manner avoiding disturbance of adjacent elements whereby displacement of the elastomeric foam material of said first support member about each said first interconnect element is limited generally to the local region of each corresponding said first element.   
     
     
       3. The apparatus of claim 1 wherein said decoupling capacitor comprises: a capacitive element having a pair of opposed surfaces;   a first multi-sided conductor on one of said opposed surfaces of said capacitive element;   a second multi-sided conductor on the other of the said opposed surfaces of said capacitive element;   a plurality of first skirt means extending outwardly and downwardly from said first conductor, one each of said first skirt means extending from at least two of said sides of said first conductor, at least one of said first skirt means being connected to one of said at least one second pad of said circuit board means and being in communication with said first voltage level; and   a plurality of second skirt means extending outwardly and downwardly from said second conductor, one each of said second skirt means extending from at least two of said sides of said second conductor, at least one of said second skirt means being connected to one of said at least one fourth pad of said circuit board means and being in communication with said second voltage level.   
     
     
       4. The apparatus of claim 3 wherein said decoupling capacitor means further includes: an insulating material surrounding said first and second conductors with said first and second skirt means extending through said insulating material.   
     
     
       5. The apparatus of claim 3 wherein: said capacitive element comprises a flat layer of dielectric material.   
     
     
       6. The apparatus of claim 3 wherein: said first and second conductors have a rectangular shape with each conductor having two of said skirt means, each one of said skirt means extends from opposed sides of each conductor.   
     
     
       7. The apparatus of claim 1 wherein said decoupling capacitor comprises: a capacitive element having a pair of opposed surfaces;   a first multi-sided conductor on one of said opposed surfaces of said capacitive element;   a second multi-sided conductor on the other of the said opposed surfaces of said capacitive element;   a plurality of first solder bump means extending downwardly from one surface of said first conductor, at least one of said first solder bump means being connected to one of said at least one second pad of said circuit board means and being in communication with said first voltage level; and   a plurality of second solder bump means extending downwardly from one surface of said second conductor, said second solder bump means extending in the same direction as said first solder bump means, at least one of said second solder bump means being connected to one of said at least one fourth pad of said circuit board means and being in communication with said second voltage level.   
     
     
       8. The apparatus of claim 7 wherein said decoupling capacitor means further includes: an insulating material surrounding said first and second conductors with said first and second solder bump means extending through said insulating material.   
     
     
       9. The apparatus of claim 7 wherein: said capacitive element comprises a flat layer of dielectric material.   
     
     
       10. The apparatus of claim 1 wherein said decoupling capacitor comprises: a capacitive element having a pair of opposed surfaces;   a first multi-sided conductor on one of said opposed surfaces of said capacitive element;   a second multi-sided conductor on the other of the said opposed surfaces of said capacitive element;   a non-conductive substrate whereupon one surface of said second conductor is disposed:   a plurality of first terminal means extending downwardly from said first conductor, one each of said first terminal means extending from at least two of said sides of said first conductor and extending adjacent to the corresponding sides of said substrate, at least one of said first terminal means being connected to one of said at least one second pad of said circuit board means and being in communication with said first voltage level; and   a plurality of second terminal means extending downwardly from said second conductor, one each of said second terminal means extending from at least two of said sides of said second conductor and extending adjacent to the corresponding sides of said substrate, at least one of said second terminal means being connected to one of said at least one fourth pad of said circuit board means and being in communication with said second voltage level.   
     
     
       11. The apparatus of claim 10 wherein said decoupling capacitor further includes: an insulating material disposed on one surface of said first conductor and extending downwardly along said sides of said first and second conductors to said substrate with said first and second terminal means extending through said insulating material.   
     
     
       12. The apparatus of claim 10 wherein: said capacitive element comprises a flat layer of dielectric material.   
     
     
       13. The apparatus of claim 10 wherein: said first and second conductors have a rectangular shape with each conductor having two of said terminal means, each one of said terminal means extends from opposed sides of each conductor.   
     
     
       14. The apparatus of claim 1 wherein said decoupling capacitor comprises: a capacitive element having a pair of opposed surfaces;   a first multi-sided conductor on one of said opposed surfaces of said capacitive element;   a second multi-sided conductor on the other of the said opposed surfaces of said capacitive element;   first surface mount terminal means extending outwardly and downwardly from one side of said first conductor, said first surface mount terminal means being connected to one of said at least one second pad of said circuit board means and being in communication with said first voltage level; and   second surface mount terminal means extending outwardly and downwardly from one side of said second conductor, said second surface mount terminal means being connected to one of said at least one fourth pad of said circuit board means and being in communication with said second voltage level.   
     
     
       15. The apparatus of claim 14 wherein said decoupling capacitor further includes: an insulating material surrounding said first and second conductors with said first and second surface mount terminal means extending through said insulating material.   
     
     
       16. The apparatus of claim 14 wherein: said capacitive element comprises a flat layer of dielectric material. .Iadd.   
     
     
       17.  An electronic subassembly comprising: a discrete integrated circuit (IC) package, said IC package having an array of contacts on one surface thereof surrounding a contact free area, at least one of said contacts being a first contact, said first contact being receptive to a first voltage level, at least one other of said contacts being a second contact, said second contact being receptive to a second voltage level;   a circuit board means having a plurality of pads, an array of which corresponds to said array of contacts of said IC package, at least one first pad corresponding to said at least one first contact, said first pad being electrically connected to at least one second pad and having said first voltage level thereon, at least one other of said pads being a third pad, said at least one third pad corresponding to said at least one second contact, said third pad being electrically connected to at least one fourth pad and having said second voltage level hereon, said second and fourth pads being disposed at an area on said circuit board means corresponding to said contact free area of said IC; and   a first compressible connector means sandwiched between said IC package and said circuit board means, said connector means directly electrically and mechanically interconnecting said IC package to said circuit board means, said first compressible connector means including an opening therethrough, said opening being disposed under said contract free area of said IC package;   a decoupling capacitor disposed in said opening and connected to said circuit board means said decoupling capacitor providing decoupling capacitance between said first and second voltage levels on said IC package, said decoupling capacitor being in communication with said second and fourth pads on stud circuit board means..Iaddend..Iadd.18. The electronic subassembly of claim 17 wherein:   said discrete IC package comprises a land grid array package..Iaddend..Iadd.19. The electronic subassembly of claim 17 wherein said compressible connector means comprises:   an electrically non-conductive resilient elastomeric foam support member;   an array of spaced movable electrically conductive interconnect elements supported in said support member, said array of interconnect elements corresponding to said array of contacts of said IC package wherein said interconnect elements are movable between (1) a connected position where said elements electrically interconnect said array of contacts to said pads on said circuit board means and (2) a disconnected position where said elements are electrically out of contact with said array of contacts   
     
     
        and said pads..Iaddend..Iadd.20.  The apparatus of claim 3 wherein said first compressible connector means comprises: a first electrically non-conductive support member having an array of apertures therethrough said first support member comprising resilient elastomeric foam material, said first support member having support surfaces to be respectively opposed to the surfaces of said circuit board means and said land grid array package and being adapted to be compressed by urging said circuit board means said IC package together; and   a first plurality of bodily rotatable, electrically conductive interconnect elements, each comprising a body extending generally in the direction of the thickness of the resilient elastomeric foam support member and tab portions projecting angularly from the respective ends of said body, each of said first elements defining a pair of engagement surfaces disposed to engage respective ones of corresponding said pads of said circuit board means at one end and to engage respective ones of corresponding said contacts of said IC package at the other end, a line projected through said engagement surfaces being disposed at an initial acute angle to the direction of thickness of said first support member, and said tab portions defining engagement surfaces disposed at least closely in opposition to said support surfaces of said first support member to engage upon said support surfaces during bodily rotation of said first interconnect element to locally compress the elastomeric foam of said first support member, whereby, when said first compressible connector means is disposed between said circuit board means and said IC package in a clamped together relationship with said first interconnect elements in registry with said corresponding pads of said circuit board means and said corresponding contacts of said IC package, and with said first interconnect elements rotated bodily as a result of said clamping so that said line projected through said engagement surfaces of each element has at an acute angle resiliently supported by said elastomeric foam to bear with force upon said pads of said circuit board means and said contacts of said IC package, and of said elastomeric foam of said first support member serve locally to accommodate bodily rotation of said first interconnect elements in a manner avoiding disturbance of adjacent element whereby displacement of the elastomeric foam material of said first support member about each said first interconnect element is limited generally to the local region of each corresponding said first element..Iaddend.