Methods of forming polymeric structures using carbon dioxide and polymeric structures formed thereby

Abstract

Methods of forming a polymeric structure having a plurality of cells therein that include contacting a polymeric material that includes a first phase and a second phase with a composition comprising carbon dioxide to form the polymeric structure having a plurality of cells therein are described. Polymeric materials and microelectronic devices formed by such methods are also described.

That which is claimed is:  
     
         1 . A polymer structure comprising: 
 a polymeric matrix having a plurality of cells therein, wherein the cells in the plurality of cells have an average diameter of from about 1 to 25 nm.    
     
     
         2 . The polymer structure of  claim 1 , wherein the cells in the plurality of cells have an average diameter of from about 2 to 20 nm.  
     
     
         3 . The polymer structure of  claim 1 , wherein the cells in the plurality of cells have an average diameter of from about 3 to 15 nm.  
     
     
         4 . The polymer structure of  claim 1 , wherein the cells in the plurality of cells have an average diameter of from about 4 to 12 nm.  
     
     
         5 . The polymer structure of  claim 1 , wherein the cells in the plurality of cells have an average diameter of from about 3 to 10 nm.  
     
     
         6 . The polymer structure of  claim 1 , wherein the cells in the plurality of cells have an average diameter of from about 5 to 8 nm.  
     
     
         7 . The polymer structure of  claim 1 , wherein the plurality of cells comprise closed cells.  
     
     
         8 . The polymer structure of  claim 1 , wherein the polymeric matrix comprises a polymer selected from the group consisting of a polystyrene, a polyimide, a fluoropolymer, a poly(arylene)ether, a polyphenylene, SiLK™, and combinations thereof.  
     
     
         9 . The polymer structure of  claim 1 , wherein the polymeric matrix has a dielectric constant of about 1.5 to 3.5.  
     
     
         10 . The polymer structure of  claim 1 , wherein the polymeric matrix has a density of cells from about 0.2 to 1 g/cm 3  polymeric material.  
     
     
         11 . A microelectronic device comprising: 
 a dielectric material that comprises a polymeric matrix having a plurality of cells therein, wherein the cells in the plurality of cells have an average diameter of from about 1 to 25 nm.    
     
     
         12 . The microelectronic device of  claim 11 , wherein the cells in the plurality of cells have an average diameter of from about 2 to 20 nm.  
     
     
         13 . The microelectronic device of  claim 11 , wherein the cells in the plurality of cells have an average diameter of from about 3 to 15 nm.  
     
     
         14 . The microelectronic device of  claim 11 , wherein the cells in the plurality of cells have an average diameter of from about 4 to 12 nm.  
     
     
         15 . The microelectronic device of  claim 11 , wherein the cells in the plurality of cells have an average diameter of from about 3 to 10 nm.  
     
     
         16 . The microelectronic device of  claim 11 , wherein the cells in the plurality of cells have an average diameter of from about 5 to 8 nm.  
     
     
         17 . The microelectronic device of  claim 11 , wherein the plurality of cells comprise closed cells.  
     
     
         18 . The microelectronic device of  claim 11 , wherein the polymeric matrix comprises a polymer selected from the group consisting of a polystyrene, a polyimide, a fluoropolymer, a poly(arylene)ether, a polyphenylene, SiLK™, and combinations thereof.  
     
     
         19 . The microelectronic device of  claim 11 , wherein the dielectric material has a dielectric constant of about 1.5 to 3.5.  
     
     
         20 . The microelectronic device of  claim 11 , wherein the polymeric matrix has a density of cells from about 0.2 to 1 g/cm 3  polymeric material.