Folded interposer

Abstract

A folded interposer used to achieve a high density semiconductor package is disclosed. The folded interposer is comprised of a thin, flexible material that can be folded around one or multiple semiconductor dice in a serpentine fashion. The semiconductor dice are then attached to a substrate through electrical contacts on the interposer. The folded interposer allows multiple semiconductor dice to be efficiently stacked in a high density semiconductor package by reducing the unused or wasted space between stacked semiconductor dice. Vias extending through the folded interposer provide electrical communication between the semiconductor dice and the substrate. The present invention also relates to a method of packaging semiconductor dice in a high density arrangement and a method of forming the high density semiconductor package.

1 . A folded interposer comprising: 
 a thin, flexible material comprised of a first surface and a second surface, the material for folding around at least one semiconductor die, the material having substantially the same width as the at least one semiconductor die;    a plurality of vias extending from the first surface to the second surface; and    a plurality of electrical contacts on the first surface of the material.    
   
   
       2 . The interposer of  claim 1 , wherein the material comprises an insulative polymer.  
   
   
       3 . The interposer of  claim 2 , wherein the material further comprises a thermally conductive material.  
   
   
       4 . The interposer of  claim 1 , wherein the second surface surrounds at least three sides of the at least one semiconductor die around which the interposer is folded.  
   
   
       5 . The interposer of  claim 1 , wherein the second surface surrounds at least two sides of the at least one semiconductor die around which the interposer is folded.  
   
   
       6 . The interposer of  claim 1 , wherein each of the plurality of electrical contacts is applied to the second surface of the material.  
   
   
       7 . A high density semiconductor package having at least two semiconductor dice comprising: 
 a substrate having at least one contact pad on a surface thereof; and    a flexible interposer folded around a first semiconductor die of the at least two semiconductor dice, the interposer including a first surface having a plurality of electrical contacts for electrically connecting the first semiconductor die to the substrate, a second surface, and a plurality of vias extending through the interposer from the first surface to the second surface, the first semiconductor die having a plurality of bond pads on a surface thereof and a back surface, the first semiconductor die positioned in a back-to-back configuration with another semiconductor die of the at least two semiconductor dice and attached to the interposer to form an intermediate packaging structure; at least one electrical contact of the plurality of electrical contacts of the flexible interposer connected to the at least one contact pad of the substrate.    
   
   
       8 . The package of  claim 7 , wherein each of the plurality of vias is filled with conductive metal.  
   
   
       9 . The package of  claim 7 , wherein the second surface surrounds at least three sides of the first semiconductor die around which the interposer is folded.  
   
   
       10 . The package of  claim 7 , wherein the second surface surrounds at least two sides of the first semiconductor die around which the interposer is folded.  
   
   
       11 . The package of  claim 7 , wherein at least one bond pad of the plurality of bond pads of the first semiconductor die is in electrical communication with at least one electrical contact of the plurality of electrical contacts of the flexible interposer through the plurality of vias therein.  
   
   
       12 . The package of  claim 7 , wherein the interposer folds around more than two semiconductor dice by weaving in a serpentine fashion around groups of semiconductor dice, each group including two semiconductor dice.  
   
   
       13 . The package of  claim 7 , wherein the substrate comprises a semiconductor device.  
   
   
       14 . The package of  claim 7 , wherein the substrate further comprises a printed circuit board.  
   
   
       15 . The package of  claim 7 , further comprising electrical contacts applied to a top surface of the package.  
   
   
       16 . An interposer comprising: 
 a thin, flexible material comprised of a first surface and a second surface, the material for folding around at least one semiconductor die, the material having substantially the same width as the at least one semiconductor die;    a plurality of vias extending from the first surface to the second surface; and    a plurality of electrical contacts on the first surface of the material.    
   
   
       17 . The interposer of  claim 16 , wherein the material comprises an insulative polymer.  
   
   
       18 . The interposer of  claim 17 , wherein the material further comprises a thermally conductive material.  
   
   
       19 . The interposer of  claim 16 , wherein the second surface surrounds at least three sides of the at least one semiconductor die around which the interposer is folded.  
   
   
       20 . The interposer of  claim 16 , wherein each of the plurality electrical contacts is applied to the second surface of the interposer.