Injection of a filler material with homogeneous distribution of anisotropic filler particles through implosion

Abstract

A method for providing a matrix material between a bonded pair of substrates with a homogeneous distribution of anisotropic filler particles is provided. Functionalized anisotropic filler particles are mixed uniformly with a matrix material to form a homogenous mixture. A bonded assembly of a first substrate and a second substrate with an array of electrical interconnect structures is placed within a vacuum environment. The homogenous mixture of the matrix material and the anisotropic filler particles is dispensed around the array of electrical interconnect structures. A gas is abruptly introduced into the vacuum environment to induce an implosion of the homogenous mixture. The implosion causes the homogenous mixture to fill the cavity between the first and second substrates without causing agglomeration of the anisotropic filler particles. The mixture filling the space between the first and second substrates has a homogenous distribution of the anisotropic filler particles.

What is claimed is: 
     
         1 . A structure comprising:
 a first substrate and a second substrate that are bonded to each other through an array of electrical interconnect structures; and   a mixture of an underfill material and anisotropic filler particles embedding said array of electrical interconnect structures and located between said first and second substrates, wherein a density of said anisotropic filler particles is uniform throughout an entirety of said mixture.   
     
     
         2 . The structure of  claim 1 , wherein said mixture has a contiguous surface contacting said first substrate at a first periphery having a closed shape and contacting said second substrate at a second periphery having another closed shape. 
     
     
         3 . The structure of  claim 2 , wherein said first periphery is formed on a planar top surface of said first substrate, and said second periphery is formed on sidewalls of said second substrate. 
     
     
         4 . The structure of  claim 1 , wherein said underfill material and said anisotropic filler particles comprise insulator materials. 
     
     
         5 . The structure of  claim 1 , wherein said anisotropic filler particles are selected from silicon carbide nanowires, halloysite nanowires, nanowires of at least one metallic material, carbon nanotubes, polymer nanofibers, and combinations thereof. 
     
     
         6 . The structure of  claim 1 , wherein said anisotropic filler particles are selected from platelets of a material selected from graphene, graphene oxide, boron nitride, a thermoplastic material, and combinations thereof. 
     
     
         7 . The structure of  claim 1 , wherein said anisotropic filler particles comprise a material having thermal conductivity greater than 0.2 W/(m.K). 
     
     
         8 . The structure of  claim 1 , wherein said anisotropic filler particles have a functionalizing coating that retards agglomeration thereamongst. 
     
     
         9 . The structure of  claim 1 , wherein said anisotropic filler particles have a ratio of a maximum dimension to a minimum dimension that is greater than 3.0. 
     
     
         10 . The structure of  claim 1 , wherein said anisotropic filler particles have a volume fraction less than 0.1 within said mixture after said implosion.