High density integrated circuit apparatus, test probe and methods of use thereof

Abstract

The present invention is directed to a high density test probe which provides a means for testing a high density and high performance integrated circuits in wafer forms or as discrete chips. The test probe is formed from a dense array of elongated electrical conductors which are embedded in an compliant or high modulus elastomeric material. A standard packaging substrate, such as a ceramic integrated circuit chip packaging substrate is used to provide a space transformer. Wires are bonded to an array of contact pads on the surface of the space transformer. The space transformer formed from a multilayer integrated circuit chip packaging substrate. The wires are as dense as the contact location array. A mold is disposed surrounding the array of outwardly projecting wires. A liquid elastomer is disposed in the mold to fill the spaces between the wires. The elastomer is cured and the mold is removed, leaving an array of wires disposed in the elastomer and in electrical contact with the space transformer. The space transformer can have an array of pins which are on the opposite surface of the space transformer opposite to that on which the elongated conductors are bonded. The pins are inserted into a socket on a second space transformer, such as a printed circuit board to form a probe assembly. Alternatively, an interposer electrical connector can be disposed between the first and second space transformer.

1 - 28 . (canceled)  
   
   
       29 . A method of probing an electronic component by contacting the electronic component with a plurality of flexible contact elements, the method comprising the steps of: 
 providing a first substrate corresponding to an area of the electronic component to be probed, said substrate having a front surface;    mounting and connecting a second substrate to the front surface of the first substrate, said second substrate having a plurality of flexible contact elements bonded to and extending from a surface thereof;    urging the first substrate and the electronic component towards one another so that the flexible contact elements make contact with a surface of the electronic component shape;    the flexible contact elements flex and wipe the surface of the electronic component when the flexible contacts contact the electronic components;    the flexible contact elements substantially compliantly respond when the flexible contact elements are withdrawn from contacting the electronic component; and    aligning the second substrate to the first substrate to align the flexible contact elements to the electronic component.    
   
   
       30 . A method according to  claim 29 , wherein the electronic component is a semiconductor wafer.  
   
   
       31 . A method according to  claim 30 , wherein the area is a plurality of integrated circuits on the semiconductor wafer; and the flexible contacts make contact with the plurality of die sites all at once.  
   
   
       32 . A method according to  claim 29 , wherein the area of the electronic component is a portion of a surface area of the electronic component.  
   
   
       33 . A method according to  claim 29 , wherein the flexible elements are probe elements.  
   
   
       34 . A method according to  claim 29 , wherein there are electrical connections between the second substrates and the first substrate.  
   
   
       35 . A method according to  claim 29 , wherein the first substrate is a space transformer.  
   
   
       36 . A method according to  claim 29 , wherein the electronic component is a semiconductor wafer; and the flexible contact elements of the second substrate contact individual semiconductor dies on the semiconductor wafer.  
   
   
       37 . A method according to  claim 29 , wherein the electronic component is a semiconductor wafer; and the flexible contact elements of the second substrate contacts at least one integrated circuit on the semiconductor wafer.  
   
   
       38 . A method of probing an electronic device according to  claim 29  wherein: 
 urging the first substrate and the electronic device towards one another so that the flexible contact elements make contact with the surface of the electronic component comprising a free end of the flexible contact elements laterally move when pressed against the area of the electronic device, and the first substrate with the second substrate mounted thereto is mounted to an electrical testing apparatus; and    
   
   
       39 . A method according to  claim 29 , wherein the first substrate with the second substrate mounted thereto is mounted to an electrical testing apparatus by a plurality of electrical connections.  
   
   
       40 . A probe structure comprising an assembly comprising: 
 a first substrate having a top surface, a bottom surface, a first plurality of terminals disposed on the top surface, and a second plurality of terminals disposed on the bottom surface;    at least one second substrate having a top surface and a bottom surface;    means for effecting electrical connections between the at least one second substrate and the first substrate;    a plurality of probe elements disposed on the top surface of the at least one second substrate;    the probe elements are free-standing flexible conductors shaped so that a free end thereof laterally movers when pressed against a surface; and    means for aligning the second substrate to the first substrate to align the flexible contact elements to the electronic component.    
   
   
       41 . A structure according to  claim 40 , wherein the probe elements are free-standing flexible conductors.  
   
   
       42 . A structure according to  claim 40 , wherein protuberances are deposed at ends of the plurality of free-standing flexible conductors.  
   
   
       43 . A structure according to  claim 40 , wherein the free-standing flexible conductor further includes a protuberance at an end thereof.  
   
   
       44 . A method according to  claim 29 , further including plurality of groups of said plurality of the flexible electrical contact elements.  
   
   
       45 . A method according to  claim 29 , wherein there is a least one of said second substrates mounted to said first substrate.  
   
   
       46 . A method according to  claim 29 , wherein there are a plurality of said second substrates mounted to said first substrate.  
   
   
       47 . A method according to  claim 33  where each of said plurality of flexible contact elements flex and wipe the area of the electronic device when said flexible contacts contact the electronic component; the flexible contact element substantially compliantly respond when the flexible contact element are withdrawn from contacting the electronic component.  
   
   
       48 . A method according to  claim 29 , wherein the flexible contact elements can be repeatably assembled and disassembled so that said flexible contact element can recontact, reflex and rewipe the area of the electronic device.  
   
   
       49 . A method according to  claim 47 , wherein the rewiped area is an area selected from the group consisting of an area of the same or a different electronic device.  
   
   
       50 . A structure according to  claim 49 , wherein the flexible contact elements are said free standing flexible conductors comprise a coating.  
   
   
       51 . A structure according to  claim 50  wherein said coating is selected from the group consisting of Au, Cr, Co, Ni and Pd.  
   
   
       52 . A structure according to  claim 51  wherein said free standing flexible conductor comprises gold, gold alloy, copper, copper alloy, aluminum, nickel, palladium and platinum.  
   
   
       53 . A method of probing according to  claim 29  wherein said aligning is by a screw mechanism to adjust the orientation of the second substrate to the first substrate.  
   
   
       54 . A method of probing according to  claim 53  wherein the aligned first substrate and second substrate are held together with the plurality of flexible contact elements disposed in electrical contact with the electronic component.