Electronic package assembly with stiffener

Abstract

An electronic package technology is disclosed. A first active die can be mountable to and electrically coupleable to a package substrate. A second active die can be disposed on a top side of the first active die, the second active die being electrically coupleable to one or both of the first active die and the package substrate. At least one open space can be available on the top side of the first active die. At least a portion of a stiffener can substantially fill the at least one open space available on the top side of the first active die.

1 . An electronic package assembly, comprising:
 a first active die having a bottom side and a top side, the bottom side of the first active die being mountable to and electrically coupleable to a package substrate;   a second active die, disposed on the top side of the first active die, the second active die being electrically coupleable to one or both of the first active die and the package substrate; and   at least one open space available on the top side of the first active die;   a stiffener, at least a portion of which substantially fills the at least one open space available on the top side of the first active die.   
     
     
         2 . The assembly of  claim 1 , further comprising an encapsulant, encapsulating at least a portion of each of the first active die, the second active die and the stiffener. 
     
     
         3 . The assembly of  claim 1 , wherein the stiffener is more rigid than is a portion of the encapsulant corresponding in shape and size to the at least one open space. 
     
     
         4 . The assembly of  claim 1 , wherein the stiffener is electronically passive. 
     
     
         5 . The assembly of  claim 1 , further comprising one or more capacitors carried by the stiffener. 
     
     
         6 . The assembly of  claim 1 , wherein an upper surface of the stiffener is substantially level with an upper surface of the second active die. 
     
     
         7 . The assembly of  claim 1 , wherein an upper surface of the stiffener is positioned at a different height than an upper surface of the second active die. 
     
     
         8 . The assembly of  claim 1 , wherein the stiffener is attached to the first active die by a soldered connection. 
     
     
         9 . The assembly of  claim 1 , wherein the stiffener is attached to the first active die with an adhesive. 
     
     
         10 . The assembly of  claim 1 , wherein the stiffener is formed from a material selected from the group consisting of: a polymer, glass, silicon, ceramic and metal. 
     
     
         11 . The assembly of  claim 1 , wherein the stiffener has a greater thermal conductivity than does the encapsulant. 
     
     
         12 . The assembly of  claim 1 , wherein the stiffener has a coefficient of thermal expansion substantially the same as the second active die. 
     
     
         13 . The assembly of  claim 1 , wherein the stiffener includes a material having a Young's Modulus greater than the encapsulant. 
     
     
         14 . The assembly of  claim 1 , further comprising a package substrate, and wherein the first active die is mounted to and electrically coupled to the package substrate. 
     
     
         15 . The assembly of  claim 1 , wherein the second active die and the stiffener collectively cover at least about 90% of an upper surface of the first active die. 
     
     
         16 . The assembly of  claim 1 , wherein the encapsulant substantially completely encapsulates the first active die, the second active die and the stiffener. 
     
     
         17 . The assembly of  claim 1 , further comprising a plurality of stiffeners filling the at least one open space on the top side of the first active die. 
     
     
         18 . The assembly of  claim 1 , further comprising a plurality of second active dies arranged on the top side of the first active die. 
     
     
         19 . The assembly of  claim 18 , wherein at least some of the plurality of second active dies differ in size and/or shape. 
     
     
         20 - 23 . (canceled) 
     
     
         24 . A method of fabricating an electronic package assembly, comprising:
 obtaining a first active die having a bottom side and a top side, the bottom side of the first active die being mountable to and electrically coupleable to a package substrate;   positioning a second active die on the top side of the first active die while leaving an open space available on the top of the first active die;   positioning a stiffener on the top side of the first active die such that at least a portion of the stiffener substantially fills the open space available on the top side of the first active die; and   applying an encapsulant to the package assembly such that the encapsulant encapsulates at least a portion of each of the first active die, the second active die and the stiffener.   
     
     
         25 - 26 . (canceled) 
     
     
         27 . The method of  claim 24 , further comprising one or more capacitors carried by the stiffener. 
     
     
         28 . (canceled) 
     
     
         29 . The method of  claim 24 , further comprising attaching the stiffener to the first active die by a soldered connection. 
     
     
         30 . The method of  claim 24 , further comprising attaching the stiffener to the first active die with an adhesive. 
     
     
         31 - 34 . (canceled) 
     
     
         35 . The method of  claim 24 , further comprising mounting the first active die to a package substrate and electronically coupling the first active die to the substrate. 
     
     
         36 - 40 . (canceled)