Multi-chip module with extension

Abstract

A multi-chip module may include a pair of chips which are arranged one over the other on each side of a laminate layer. A central passage through the laminate layer provides a passage to wire bond a chip on a first side of the laminate layer to contacts on a second side of the laminate layer. A second chip is also placed on the second side of the laminate layer. By causing the laminate layer to extend outwardly beyond the first and second chips, and providing contacts on the extension, contact may be made to the laminate layer extension for electrically coupling the first and second chips to the outside world.

What is claimed is:  
     
         1 . A multi-chip module comprising: 
 a laminate layer having top and bottom sides and a passage;    a first chip secured to the bottom side of said layer, said first chip wire bonded to the top side of said layer through said passage;    a second chip secured to the top side of the layer and coupled by bumps to said layer; and    said layer including an extension beyond at least one of said chips, said extension including solder ball contacts on said bottom side, electrically coupled to said first and second chips.    
     
     
         2 . The module of  claim 1  including a pair of opposed extensions each extending outwardly beyond the rest of the module and each having contacts.  
     
     
         3 . The module of  claim 1  wherein said extension extends all the way around said module.  
     
     
         4 . The module of  claim 1  wherein said first chip is bonded to said layer using adhesive securement.  
     
     
         5 . The module of  claim 4  wherein said adhesive securement is adhesive tape.  
     
     
         6 . The module of  claim 1  wherein the overall height of said module is approximately one millimeter or less.  
     
     
         7 . The module of  claim 1  wherein said first and second chips are aligned one over the other and centered over said passage.  
     
     
         8 . The module of  claim 7  wherein said passage is centered in said layer.  
     
     
         9 . The module of  claim 1  wherein said package has bilateral symmetry.  
     
     
         10 . The module of  claim 1  wherein said region between said first and second chips is filled with encapsulant.  
     
     
         11 . The module of  claim 1  wherein said extension extends outwardly beyond said first and second chips.  
     
     
         12 . A method of forming a multi-chip module comprising: 
 adhesively securing a first chip to a first surface of a laminate layer;    inverting the assembly of said laminate layer and said first chip;    wire bonding said first chip to a second surface of said laminate layer;    securing a second chip to the second surface of said laminate layer using bumps;    positioning said first and second chips on said laminate layer so that at least a portion of said laminate layer extends outwardly beyond said first and second chips; and    providing solder ball contacts on said first surface of said extension electrically coupled to said first and second chips.    
     
     
         13 . The method of  claim 12  including aligning said first and second chips over one another.  
     
     
         14 . The method of  claim 13  including providing a pair of extensions extending outwardly beyond said first and second chips.  
     
     
         15 . The method of  claim 13  including aligning said chips so as to form an extension of said laminate layer that extends outwardly beyond said chips and completely around said module.  
     
     
         16 . The method of  claim 14  including providing solder balls on said contacts on said extensions.  
     
     
         17 . The method of  claim 12  including filling a region between said chips with an encapsulant.  
     
     
         18 . The method of  claim 17  including forming a passage through said laminate layer and forming wire bonds from said first chip through said passage to the second surface of said laminate layer.  
     
     
         19 . The method of  claim 17  including coupling said contact and said first and second chips through traces extending through said laminate layer.  
     
     
         20 . A multi-chip module comprising: 
 a central support layer having a top side and a bottom side, a bonding pad on each of said sides and conductive interconnections extending through said layer;    a first chip secured to the bottom side of said layer;    a second chip secured to the top side of said layer, said second chip secured by bumps to said layer; and    said layer extending outwardly beyond said first and second chips, said layer including a solder ball pad on an extension extending outwardly beyond said first and second chips for electrically connecting said chips to external devices.    
     
     
         21 . The module of  claim 20  wherein said layer is a laminate layer.  
     
     
         22 . The module of  claim 20  wherein said first chip is adhesively secured to said layer.  
     
     
         23 . The module of  claim 22  wherein said first chip is secured by adhesive tape to said layer.  
     
     
         24 . The module of  claim 20  wherein said layer includes a central aperture, said first chip wire bonded to the top side of said layer through said aperture.  
     
     
         25 . The module of  claim 20  having an overall height of less than approximately 1 millimeter.  
     
     
         26 . The module of  claim 20  wherein said extension extends outwardly beyond said first and second chips in two directions.  
     
     
         27 . The module of  claim 20  wherein said layer extends beyond said chips completely around said chips.  
     
     
         28 . The module of  claim 20  wherein said first and second chips are aligned with one another and positioned centrally on said layer.  
     
     
         29 . The module of  claim 28  wherein a passage is formed centrally through said layer for wire bonding said first chip to said layer.  
     
     
         30 . A method comprising: 
 coupling a first chip to a first side of a support structure;    coupling a second chip to a second side of said support structure;    causing said support structure to extend outwardly beyond the first chip; and    providing solder ball pads on the portion of said structure extending outwardly beyond said first chip, said pads electrically coupled to said first and second chips.    
     
     
         31 . The method of  claim 30  wherein coupling a first chip includes adhesively coupling a first chip to said support structure.  
     
     
         32 . The method of  claim 31  wherein coupling a first chip includes wire bonding said first chip to bonding pads on said second side of said support structure.  
     
     
         33 . The method of  claim 30  wherein coupling a second chip includes bump bonding said second chip to said second side of said support structure.  
     
     
         34 . The method of  claim 30  wherein causing said support structure to extend outwardly includes causing said support structure to extend outwardly from two opposed edges of the first chip.  
     
     
         35 . The method of  claim 34  wherein causing said support structure to extend outwardly includes causing said support structure to extend outwardly beyond four edges of said first chip.  
     
     
         36 . The method of  claim 30  wherein causing said support structure to extend outwardly includes causing said support structure to extend outwardly beyond said first and second chips.  
     
     
         37 . The method of  claim 30  including coupling said first and second chips to said solder ball pads on said portion via traces extending through said structure.