Controlled geometry hardmask including subresolution elements

Abstract

Methods for forming accurate, symmetric cross-section spacers of hardmask material on a substrate such as a silicon wafer or quartz substrate, for formation of precise subresolution features useful for forming integrated circuits. The resulting symmetrical hardmask spacers with their symmetric upper portions may be used to accurately etch well-defined, high aspect ratio features in the underlying substrate. Some disclosed methods also enable simultaneous formation of hardmask structures of various dimensions, of both conventional and subresolution size, to enable etching structural features of different sizes in the underlying substrate.

1 . An article of manufacture comprising: 
 a substrate; and    at least one subresolution hardmask element including a first side and a second side configured to promote etching of the substrate adjacent each of the first and second sides at substantially the same etch rate.    
   
   
       2 . The article of manufacture of  claim 1 , wherein the at least one subresolution hardmask element includes a top surface substantially perpendicular to the first and second sides thereof.  
   
   
       3 . The article of manufacture of  claim 1 , wherein the at least one subresolution hardmask element exhibits a rectangular cross-section.  
   
   
       4 . An article of manufacture comprising: 
 a substrate; and    a plurality of hardmask elements, at least some of the hardmask elements being of subresolution dimensions and at least one of the hardmask elements being of a dimension larger than subresolution.    
   
   
       5 . The article of manufacture of  claim 4 , wherein the at least some hardmask elements include a first side and a second side configured to promote etching of the substrate adjacent each of the first and second sides at substantially the same etch rate.  
   
   
       6 . The article of manufacture of  claim 4 , wherein the at least some hardmask elements exhibit a rectangular cross-section.  
   
   
       7 . The article of manufacture of  claim 4 , wherein the at least one hardmask elements comprises at least one layer of material flanked by spacers of subresolution dimension.  
   
   
       8 . The article of manufacture of  claim 7 , wherein the at least one layer of material comprises a plurality of layers.