Method of processing organic antireflection layers

Abstract

In a process for the anisotropic dry etching of an organic antireflection layer, the etching gases used are substantially hydrogen and nitrogen.

We claim:  
     
         1 . A process for anisotropically dry etching of an organic antireflection layer, which comprises etching the organic antireflection layer with an etching gas composition primarily containing hydrogen and nitrogen.  
     
     
         2 . The process according to  claim 1 , which comprises etching the organic antireflection layer with an etching gas composition consisting essentially of hydrogen and nitrogen.  
     
     
         3 . The process according to  claim 1 , which comprises using hydrogen and nitrogen in a ratio of 1:1.  
     
     
         4 . The process according to  claim 1 , which comprises etching with an etching gas composition containing at least 80% hydrogen and nitrogen as reactive etching gases.  
     
     
         5 . The process according to  claim 4 , wherein the etching gas composition contains, as reactive etching gases, only hydrogen and nitrogen.  
     
     
         6 . The process according to  claim 1 , which comprises etching with an etching gas composition containing additives for improving etching gas properties in the dry etching process.  
     
     
         7 . The process according to  claim 1 , which comprises using a photoresist layer as an etching mask for the organic antireflection layer, and setting the etching gas composition such that a vertical removal of the photoresist corresponds at most to an etching rate of the organic antireflection layer.  
     
     
         8 . The process according to  claim 1 , which comprises setting the following process parameters for the reactive ion etching of the organic antireflection layer: 
 pressure of the etching gases in a range between 2.67 and 26.67 Pa; and    flow of the etching gases in a range between 0.17 and 1.67 10 −6  m 3  sec −1 .    
     
     
         9 . The process according to  claim 8 , which comprises exposing an etching object to a magnetic field strength from 0 to 120 Gauss and processing the object with magnetic field-assisted reactive ion etching.  
     
     
         10 . The process according to  claim 1 , which comprises etching the organic antireflection layer with a plasma from a source selected from the group consisting of an electron cyclone resonance plasma source, an inductively coupled plasma, or a Helicon source.